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1.
World J Gastroenterol ; 30(36): 4044-4056, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39351251

RESUMO

BACKGROUND: Radiomics has been used in the diagnosis of cirrhosis and prediction of its associated complications. However, most current studies predict the risk of esophageal variceal bleeding (EVB) based on image features at a single level, which results in incomplete data. Few studies have explored the use of global multi-organ radiomics for non-invasive prediction of EVB secondary to cirrhosis. AIM: To develop a model based on clinical and multi-organ radiomic features to predict the risk of first-instance secondary EVB in patients with cirrhosis. METHODS: In this study, 208 patients with cirrhosis were retrospectively evaluated and randomly split into training (n = 145) and validation (n = 63) cohorts. Three areas were chosen as regions of interest for extraction of multi-organ radiomic features: The whole liver, whole spleen, and lower esophagus-gastric fundus region. In the training cohort, radiomic score (Rad-score) was created by screening radiomic features using the inter-observer and intra-observer correlation coefficients and the least absolute shrinkage and selection operator method. Independent clinical risk factors were selected using multivariate logistic regression analyses. The radiomic features and clinical risk variables were combined to create a new radiomics-clinical model (RC model). The established models were validated using the validation cohort. RESULTS: The RC model yielded the best predictive performance and accurately predicted the EVB risk of patients with cirrhosis. Ascites, portal vein thrombosis, and plasma prothrombin time were identified as independent clinical risk factors. The area under the receiver operating characteristic curve (AUC) values for the RC model, Rad-score (liver + spleen + esophagus), Rad-score (liver), Rad-score (spleen), Rad-score (esophagus), and clinical model in the training cohort were 0.951, 0.930, 0.801, 0.831, 0.864, and 0.727, respectively. The corresponding AUC values in the validation cohort were 0.930, 0.886, 0.763, 0.792, 0.857, and 0.692. CONCLUSION: In patients with cirrhosis, combined multi-organ radiomics and clinical model can be used to non-invasively predict the probability of the first secondary EVB.


Assuntos
Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal , Cirrose Hepática , Nomogramas , Humanos , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/epidemiologia , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/diagnóstico , Estudos Retrospectivos , Feminino , Fatores de Risco , Idoso , Medição de Risco/métodos , Fígado/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Baço/diagnóstico por imagem , Valor Preditivo dos Testes , Esôfago/diagnóstico por imagem , Esôfago/patologia , Adulto , Curva ROC , Radiômica
2.
JCI Insight ; 9(20)2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39435657

RESUMO

Solute carrier family 39, member 8 (SLC39A8), is a transmembrane transporter that mediates the cellular uptake of zinc, iron, and manganese (Mn). Human genetic studies document the involvement of SLC39A8 in Mn homeostasis, brain development, and function. However, the role and pathophysiological mechanisms of SLC39A8 in the central nervous system remain elusive. We generated Slc39a8 neuron-specific knockout (Slc39a8-NSKO) mice to study SLC39A8 function in neurons. The Slc39a8-NSKO mice displayed markedly decreased Mn levels in the whole brain and brain regions, especially the cerebellum. Radiotracer studies using 54Mn revealed that Slc39a8-NSKO mice had impaired brain uptake of Mn. Slc39a8-NSKO cerebellums exhibited morphological defects and abnormal dendritic arborization of Purkinje cells. Reduced neurogenesis and increased apoptotic cell death occurred in the cerebellar external granular layer of Slc39a8-NSKO mice. Brain Mn deficiency in Slc39a8-NSKO mice was associated with motor dysfunction. Unbiased RNA-Seq analysis revealed downregulation of key pathways relevant to neurodevelopment and synaptic plasticity, including cAMP signaling pathway genes. We further demonstrated that Slc39a8 was required for the optimal transcriptional response to the cAMP-mediated signaling pathway. In summary, our study highlighted the essential roles of SLC39A8 in brain Mn uptake and cerebellum development and functions.


Assuntos
Proteínas de Transporte de Cátions , Cerebelo , Homeostase , Manganês , Camundongos Knockout , Animais , Manganês/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/deficiência , Camundongos , Cerebelo/metabolismo , Cerebelo/crescimento & desenvolvimento , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Neurônios/metabolismo , Neurogênese/genética , Masculino
3.
Biochimie ; 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369941

RESUMO

The extracellular matrix (ECM) is a complex, non-cellular network of molecules that offers structural support for cells and tissues. The ECM is composed of various structural components, including collagen, fibronectin, laminin, perlecan, nidogen, tenascin, and fibulin, which are capable of binding to each other and to cell-to-adhesion receptors, endowing the ECM with unique physical and biochemical properties that are essential for its function in maintaining health and managing disease. Over the past three decades, extensive research has shown that the core of the ECM can significantly impact cellular events at the molecular level. Structural modifications have also been strongly associated with tissue repair. Through interactions with cells, matrix proteins regulate critical processes such as cell proliferation and differentiation, migration, and apoptosis, essential for maintaining tissue homeostasis, formation, and regeneration. This review emphasizes the interlocking networks of ECM macromolecules and their primary roles in tissue regeneration and wound repair. Through studying ECM dynamics, researchers have discovered molecular signaling pathways that demonstrate how the ECM influences protein patterns and open up more possibilities for developing therapeutics that target the ECM to enhance wound repair and tissue regeneration.

4.
FASEB J ; 38(18): e70047, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39292527

RESUMO

Dermal white adipose tissue (DWAT) is a distinctive adipose depot located within the lower dermis of the skin. Its significance as an ancillary fat in skin homoeostasis has recently received increased attention. New research has revealed that DWAT responses to skin pathology and physiology changes, impacting skin development, hair cycling, defense mechanisms, and fibrotic conditions. In this review, we explore the developmental process of DWAT and the adipose commitment timing of hypodermal. We explore the development process of DWAT and its pivotal role in regulating the hair cycle. We conclude the antibacterial activity and reversible dedifferentiation of dermal adipocytes in response to skin defense. Furthermore, we underscore the potentially crucial yet underestimated anti-fibrotic functions of DWAT-derived adipokines and adipocyte-myofibroblast transition.


Assuntos
Tecido Adiposo Branco , Fibrose , Folículo Piloso , Humanos , Tecido Adiposo Branco/metabolismo , Animais , Pele/metabolismo , Pele/patologia , Adipócitos/metabolismo , Derme/patologia , Derme/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-38992183

RESUMO

Mifepristone, a progesterone receptor antagonist, was initially used to terminate early pregnancy. As scientific research advanced, it emerged to be effective in the treatment of various tumors and tumor-like conditions such as endometriosis. Despite the therapeutic potential of mifepristone, its therapeutic effect is still far from ideal because the drug is difficult to dissolve and to accumulate in the target tissue sites. To address this issue, mifepristone-loaded nanostructured lipid carriers (Mif-NLC) were prepared by a simple solvent diffusion method and their anti-endometriosis performance and mechanisms were initially investigated. By optimizing the preparation protocol, we obtained uniform and spheroidal Mif-NLC with an average particle size of 280 nm. The encapsulation rate and drug loading capacity were 64.67% ± 0.15% and 2.7% ± 0.014%, respectively, as measured by UV spectrophotometry. The in vitro release kinetics indicated that mifepristone was released from NLC in a sustained-release manner. Compared with free mifepristone, Mif-NLC exhibited enhanced cellular uptake and inhibition of invasion activity in primary mesenchymal cells of endometriosis. A certain reduction in the size of endometriotic cysts was observed in animals compared to controls. The induction of autophagy via Mif-NLC may serve as the molecular mechanism underlying this effect. Furthermore, observation of uterine structures showed negligible toxic effects. This suggested that mifepristone encapsulated in NLC can improve its bioavailability and anti-endometriosis efficacy, which provided a new strategy for the treatment of endometriosis.

6.
J Colloid Interface Sci ; 673: 143-152, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38875785

RESUMO

Conducting polymer hydrogels with inherent flexibility, ionic conductivity and environment friendliness are promising materials in the fields of energy storage. However, a trade-off between mechanical and electrochemical properties has limited the development of flexible/stretchable conducting polymer hydrogel electrodes, owing to the intrinsic conflict among mechanical and electrical phases. Here, we report a reliable design to enable conducting polymer with both exceptional mechanical and electrical/electrochemical performance through the construction of bi-continuous conducting polymer crosslinked network. The resultant bi-continuous conducting polymer hydrogels (BCPH) demonstrate significantly improved mechanical and electrochemical properties compared to the conventional conducting polymer hydrogel (CPH) electrode. BCPH presents a high specific capacitance of 715 F g-1 at 0.5 A/g, a high mechanical strength (∼1 MPa) and a large stretchability (∼300%). Enabled by such intrinsically deformability and electrochemical properties, we further demonstrate its utility in flexible solid-state supercapacitor (FSSC), which exhibits an outstanding specific capacitance of 760 mF cm-2 at 2 mA cm-2, excellent electrochemical stability with 81% capacitance retention after 5000 charge/discharge cycles, and superior bending cycle stability. This simple and scalable strategy provides a platform for the fabrication of high-performance conducting hydrogel electrodes for various wearable electronic equipment.

7.
J Colloid Interface Sci ; 669: 787-793, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38744156

RESUMO

Developing highly efficient and sustainable hydrogen evolution reaction (HER) electrocatalysts is important for the practical application of emerging energy technologies. The spherical structure and phosphorus-rich properties of Chlorella can facilitate the construction of comparable transition metal phosphide electrocatalysts. Here, a microorganism template strategy is proposed to construct a cobalt-phosphide-graphene hybrid. Chlorella can absorb metal ions, and the generated rough spherical nanoparticles are uniformly distributed around the reduced graphene oxide nanosheets. This designed catalyst has comparable HER performance in acidic electrolytes and needs an overpotential of only 153 mV at a current density of 10 mA cm-2. The experimental and density functional theory results imply that the charge redistribution between Co2P and pyrrole-N is the key factor in enhancing the HER activity. The induced electron aggregation at the N and P sites can serve as a key active site for absorbing the adsorbed hydrogen atom intermediate to accelerate the HER process, contributing to the active sites of Co2P- and pyrrole-N-doped carbon with 0 eV hydrogen adsorption free energy. This work provides a broad idea for synthesizing advanced catalysts by a biological template approach, facilitating the innovative integration of biology and emerging electrochemical energy technologies.

8.
Curr Res Food Sci ; 8: 100743, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681524

RESUMO

In starch gel foods processing, lactic acid fermentation is an effective strategy to improve the quality of the gel. This study revealed the effects of Lactobacillus plantarum fermentation for rice on the textural and rheological properties of the corresponding gels. The hardness, adhesiveness and chewiness of the gel showed ascending trends with the forwarding of fermentation. The role of Lactobacillus plantarum on rheological properties of gel depended on fermentation time. As the time was within 3 days, the process reduced the viscoelastic of the gel, while as the time was for 5 days, the process enhanced the viscoelastic of the gel. During fermentation, amylose content increased from 21.56 ± 1.17% to 27.39 ± 0.63%, and crude protein content descended from 12.60 ± 0.44 g/100 g DW to 4.8 ± 0.49 g/100 g DW. Total organic acids were ascending in the whole process, and lactic acid (LA), acetic acid (AA) and citric acid (CA) made the dominant contribution. The enthalpy change (ΔH) of the rice flour fermented for 5 days was significantly (p < 0.05) increased to 9.90 ± 0.24 J/g, indicating the formation of more double helix structures. These organic acids may contribute to the formation of the pores on the surface of granules by hydrolyzing the components, which provides a channel for enzymes to enter the interior of granules. These results provide the basis for the development of fermented rice-based foods.

9.
Front Mol Neurosci ; 17: 1365978, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660385

RESUMO

Non-coding RNAs (ncRNAs) play essential regulatory functions in various physiological and pathological processes in the brain. To systematically characterize the ncRNA profile in cortical cells, we downloaded single-cell SMART-Seq v4 data of mouse cerebral cortex. Our results revealed that the ncRNAs alone are sufficient to define the identity of most cortical cell types. We identified 1,600 ncRNAs that exhibited cell type specificity, even yielding to distinguish microglia from perivascular macrophages with ncRNA. Moreover, we characterized cortical layer and region specific ncRNAs, in line with the results by spatial transcriptome (ST) data. By constructing a co-expression network of ncRNAs and protein-coding genes, we predicted the function of ncRNAs. By integrating with genome-wide association studies data, we established associations between cell type-specific ncRNAs and traits related to neurological disorders. Collectively, our study identified differentially expressed ncRNAs at multiple levels and provided the valuable resource to explore the functions and dysfunctions of ncRNAs in cortical cells.

10.
J Adolesc Health ; 74(6): 1164-1174, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38483375

RESUMO

PURPOSE: Early school start times could adversely impact adolescent sleep duration. They could also impact other behaviors like diet and physical activity, either directly or indirectly through effects on sleep. We examined whether the double school shift system was associated with sleep, diet, and physical activity behaviors among Mexican adolescents. METHODS: The analytic sample included 305 Mexican adolescents from a cohort study (on average 14.53 ± 1.75 years old and 51% male). Sleep and physical activity were measured with wrist actigraphy, while diet and other lifestyle behaviors were assessed with questionnaires. Regression analyses were conducted to compare lifestyle behaviors between the morning and afternoon school shifts, adjusting for potential confounders. RESULTS: Adolescents attending the morning school shift (44%) had pronounced differences in sleep compared to those attending afternoon shift, including a 1.77-hour shorter sleep duration on weekdays (95% CI -1.55, -2.00), a 0.40-hour longer sleep duration on weekends (95% CI 0.10, 0.70), higher social jetlag (1.07 hours with a 95% CI of 0.87, 1.27), and an earlier chronotype. Morning shift students also had 0.85 hours longer sedentary time (95% CI 0.61, 1.10) and higher consumption of a meat and starchy food dietary pattern. Among boys only, morning shift was associated with a lower likelihood of smoking and higher consumption of a breakfast pattern. DISCUSSION: Overall, attending a morning school shift was associated with shorter sleep, more social jetlag, greater sedentary time, and higher consumption of a meat and starchy diet. However, among boys, a few healthier behaviors were observed for the morning versus afternoon shift.


Assuntos
Dieta , Exercício Físico , Estilo de Vida , Instituições Acadêmicas , Sono , Humanos , Masculino , Feminino , México , Adolescente , Sono/fisiologia , Comportamento do Adolescente/psicologia , Inquéritos e Questionários , Actigrafia , Estudantes/estatística & dados numéricos , Estudantes/psicologia , Estudos de Coortes
11.
Exp Cell Res ; 437(2): 114009, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38537745

RESUMO

Osteoarthritis (OA) is a degenerative disease that affects millions of individuals worldwide. Despite its prevalence, the exact causes and mechanisms behind OA are still not fully understood, resulting in a lack of effective treatments to slow down or halt disease progression. Recent research has discovered that extracellular vesicles (EVs) present in the circulation of young mice have a remarkable ability to activate musculoskeletal stem cells in elderly mice. Conversely, EVs derived from elderly mice do not exhibit the same potential, indicating that EVs obtained from young individuals may hold promise to activate aging cells in degenerative tissue. However, it remains unknown whether EVs derived from young individuals can also address cartilage degeneration caused by aging. In this study, we first evaluated EVs derived from young human plasma (YEVs) and EVs derived from old human plasma (OEVs) in an in vitro experiment using chondrocytes. The results revealed that YEVs effectively stimulated chondrocyte proliferation and migration, while OEVs from old plasma did not exhibit a similar effect. Given that OA represents a more complex inflammatory microenvironment, we further determine whether the benefits of YEVs on chondrocytes can be maintained in this context. Our findings indicate that YEVs have the ability to positively regulate chondrocyte function and protect them against apoptosis induced by IL-1ß and TNF-α in an in vitro OA model. Furthermore, we discovered that lyophilized EVs could be stored under mild conditions without any alterations in their physical characteristics. Considering the exceptional therapeutic effects and the wide availability of EVs from young plasma, they hold significant promise as a potential approach to activate chondrocytes and promote cartilage regeneration in early-stage OA.


Assuntos
Vesículas Extracelulares , Osteoartrite , Humanos , Camundongos , Animais , Condrócitos , Fator de Necrose Tumoral alfa/farmacologia , Cartilagem , Interleucina-1beta/farmacologia
12.
Elife ; 132024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436304

RESUMO

The entorhinal cortex is involved in establishing enduring visuo-auditory associative memory in the neocortex. Here we explored the mechanisms underlying this synaptic plasticity related to projections from the visual and entorhinal cortices to the auditory cortex in mice using optogenetics of dual pathways. High-frequency laser stimulation (HFS laser) of the visuo-auditory projection did not induce long-term potentiation. However, after pairing with sound stimulus, the visuo-auditory inputs were potentiated following either infusion of cholecystokinin (CCK) or HFS laser of the entorhino-auditory CCK-expressing projection. Combining retrograde tracing and RNAscope in situ hybridization, we show that Cck expression is higher in entorhinal cortex neurons projecting to the auditory cortex than in those originating from the visual cortex. In the presence of CCK, potentiation in the neocortex occurred when the presynaptic input arrived 200 ms before postsynaptic firing, even after just five trials of pairing. Behaviorally, inactivation of the CCK+ projection from the entorhinal cortex to the auditory cortex blocked the formation of visuo-auditory associative memory. Our results indicate that neocortical visuo-auditory association is formed through heterosynaptic plasticity, which depends on release of CCK in the neocortex mostly from entorhinal afferents.


Assuntos
Colecistocinina , Córtex Entorrinal , Camundongos , Animais , Córtex Entorrinal/fisiologia , Colecistocinina/metabolismo , Potenciação de Longa Duração/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo
13.
Sci Total Environ ; 919: 170875, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38360307

RESUMO

Poyang Lake is the largest freshwater lake in China, serving as a natural reservoir and playing a paramount role in climate regulation, ecological environment, and water resource management. However, in recent years, Poyang Lake has approached desiccation multiple times, with severe droughts becoming increasingly common. Consequently, precise quantification and analysis of the terrestrial water storage anomalies (TWSA) and drought characteristics of the Poyang Lake basin (PLB) are of profound scientific and practical significance. This paper, for the first time, utilizes data for the period 2021-2022 from 77 newly-established GNSS observation stations in the PLB to precisely determine its vertical crustal displacement, invert daily and monthly TWSA, and investigate extreme hydrological drought. The results reveal the following: 1) The annual amplitude range of vertical surface displacements at GNSS stations in the Poyang Lake basin is from 7 to 14 mm, with the most substantial seasonal vertical displacements occurring during the months of June and July; 2) monthly GNSS-TWSA maintains a commendable consistency with TWSA data obtained from the Gravity Recovery and Climate Experiment (GRACE), the Global Land Data Assimilation System (GLDAS), and precipitation, with correlation coefficients of 0.67, 0.55, and 0.62, respectively; 3) at daily scale, the GNSS-derived Drought Severity Index (GNSS-DSI) accurately recorded the severity and intensity of eight drought events in the PLB during 2021-2022, in particular the period of extensive drought between October 2021 and February 2022, when drought intensity reaching a notable 1.03, which is classified as an extreme and prolonged drought event. Additionally, at local temporal scales, daily GNSS-DSI exhibits heightened sensitivity to drought signals. This study provides novel technological tools and datasets for multi-source satellite-based drought monitoring in the PLB.

14.
J Colloid Interface Sci ; 662: 748-759, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377694

RESUMO

The increase of reaction temperature of electrocatalysts and the construction of heterogeneous structures is regarded as an efficient method to improve the electrocatalytic water splitting activity. Here, we report an approach to enhance the local heat and active sites of the catalyst by building a heterostructure with Co9S8 to significantly improve its electrocatalytic performance. The as-fabricated Co9S8@Ce-NiCo LDH/NF electrode possesses a notable photothermal ability, as it effectively converts near-infrared (NIR) light into the local heat, owing to its significant optical absorption. Leveraging these favorable qualities, the prepared Co9S8@Ce-NiCo LDH/NF electrode showed impressive performance in both hydrogen evolution reaction (HER) (η100 = 144 mV) and oxygen evolution reaction (OER) (η100 = 229 mV) under NIR light. Compared to the absence of the NIR light, the presence of NIR irradiation leads to a 24.6 % increase in catalytic efficiency for HER and a 15.8 % increase for OER. Additionally, other dual-functional electrocatalysts like NiCo-P, NiFeMo, and NiFe(OH)x also demonstrated significantly enhanced photothermal effects and improved catalytic performance owing to the augmented photothermal conversion when combined with Co9S8. This work offers novel pathways for the development of photothermal-electrocatalytic systems that facilitate economically efficient and energy-conserving overall water splitting processes.

15.
J Colloid Interface Sci ; 660: 469-477, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38246050

RESUMO

Unsaturated furanic aldehydes are derived from lignocellulosic biomass resources and subsequently used to produce valuable chemicals. However, the highly efficient, selective hydrogenation of the biomass-derived unsaturated furan CO bond remains challenging. Here we report that graphene-like nitrogen doped porous carbon (GNPC) nanosheets are synthesized from carbon-rich, sustainable, and renewable biomass precursors (glucose, fructose and 5-hydroxymethylfurfural, HMF) with high surface areas, large pore volumes and narrow mesopores. GNPC derived from HMF is an excellent catalyst support for PtCo nanoparticles with ultrafine nanoparticles size and homogeneous distributions. This catalyst is highly efficient for hydrogenation of biomass-derived furan-based unsaturated aldehydes, with high yields, to the corresponding unsaturated alcohols under mild conditions. This design strategy should further allow the development of selective, simple, green heterogeneous catalysts for challenging chemical transformations.

16.
ACS Appl Mater Interfaces ; 16(5): 6562-6568, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38273704

RESUMO

A key challenge in electrocatalysis remains controlling a catalyst's structural, chemical, and electrical properties under reaction conditions. While organic coatings showed promise for enhancing the selectivity and stability of catalysts for CO2 electroreduction (CO2RR), their impact on the chemical state of underlying metal electrodes has remained unclear. In this study, we show that organic thin films on polycrystalline copper (Cu) enable retaining Cu+ species at reducing potentials down to -1.0 V vs RHE, as evidenced by operando Raman and quasi in situ X-ray photoelectron spectroscopy. In situ electrochemical atomic force microscopy revealed the integrity of the porous organic film and nearly unaltered Cu electrode morphology. While the pristine thin film enhances the CO2-to-ethylene conversion, the addition of organic modifiers into electrolytes gives rise to improved CO2RR performance stability. Our findings showcase hybrid metal-organic systems as a versatile approach to control, beyond morphology and local environment, the oxidation states of catalysts and energy conversion materials.

17.
Front Cell Infect Microbiol ; 13: 1275086, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854857

RESUMO

Joint arthroplasty is an option for end-stage septic arthritis due to joint infection after effective control of infection. However, complications such as osteolysis and aseptic loosening can arise afterwards due to wear and tear caused by high joint activity after surgery, necessitating joint revision. Some studies on tissue pathology after prosthesis implantation have identified various cell populations involved in the process. However, these studies have often overlooked the complexity of the altered periprosthetic microenvironment, especially the role of nano wear particles in the etiology of osteolysis and aseptic loosening. To address this gap, we propose the concept of the "prosthetic microenvironment". In this perspective, we first summarize the histological changes in the periprosthetic tissue from prosthetic implantation to aseptic loosening, then analyze the cellular components in the periprosthetic microenvironment post prosthetic implantation. We further elucidate the interactions among cells within periprosthetic tissues, and display the impact of wear particles on the disturbed periprosthetic microenvironments. Moreover, we explore the origins of disease states arising from imbalances in the homeostasis of the periprosthetic microenvironment. The aim of this review is to summarize the role of relevant factors in the microenvironment of the periprosthetic tissues, in an attempt to contribute to the development of innovative treatments to manage this common complication of joint replacement surgery.


Assuntos
Osteólise , Humanos , Osteólise/etiologia , Falha de Prótese , Artroplastia/efeitos adversos
18.
Appl Opt ; 62(28): 7400-7410, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855508

RESUMO

Synchrotron-based x-ray microtomography (S-µCT) is a powerful non-invasive three-dimensional (3D) imaging technique used for visualizing the internal structure of objects with micron-scale spatial resolution. However, in practical applications, ring artifacts often occur in S-µCT, which significantly degrades image quality and hinders interpretation. In this study, we propose a ring artifact correction method based on guided image filtering (GIF). The method first extracts structural prior from the input S-µCT images and then uses it as the guidance image to correct the ring artifacts. Finally, GIF with a self-guidance image is employed to further enhance image quality. Extensive comparisons and analyses on simulations and real data experiments demonstrate that the proposed method is capable of effectively correcting ring artifacts, accompanied by low-dose noise suppression and sparse-view artifact reduction. These findings suggest that the proposed method has great potential to promote the wider applications of S-µCT in the future.

19.
Comput Struct Biotechnol J ; 21: 4159-4171, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37675287

RESUMO

Siglecs are important lectins found in different types of immune cells and function as regulatory molecules by recognizing self-associated glycans and converting extracellular interactions into signals for inhibiting immune cell functions. Although many Siglecs have been found to show broad specificities and recognize different types of sulfated oligosaccharides, Siglec-8 and Siglec-9 displayed a high degree of specificity for sialyl N-acetyllactosamine (sLacNAc) with sulfations at O6-positions of the galactose (6'-sulfation) and N-acetylglucosamine (6-sulfation), respectively. Siglec-3 was recently discovered to bind sLacNAc both sulfations. In addition to a conserved arginine residue for binding to sialic acid residue, the sequence variety in the CC' loop may provide binding specificities to sulfated oligosaccharides in Siglecs. Thus, the present study employed molecular models to study the impact of different residues in the CC' loops of Siglec-8/9/3 to the recognitions of 6-sulfations in Gal and/or GlcNAc of sLacNAc. The negatively charged residues in the CC' loop of Siglec-9 formed unfavorable electrostatic repulsions with the 6-sulfate in Gal and resulted no recognitions, in contrast to the favorable interactions formed between the positively charged residues in the CC' loop of Siglec-8 and the 6-sulfate in Gal resulting strong specificity. A two-state binding model was proposed for Siglec-3 recognizing 6-sulfations in Gal and GlcNAc of sLacNAc, as the neutral residues in the CC' loop of Siglec-3 could not form strong favorable interactions to lock the 6-sulfate in Gal within a single binding pose or strong unfavorable interactions to repel the 6-sulfate in Gal. The oligosaccharide adopted two distinctive binding poses and oriented the sulfate groups to form interactions with residues in the CC' loop and G-strand. The present study provided a structural mechanism for the sequence variety in the CC' loop of Siglec-8/9/3 determining the recognitions to the sulfated oligosaccharides and offered insights into the binding specificities for Siglecs.

20.
J Belg Soc Radiol ; 107(1): 69, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37694191

RESUMO

Synovial sarcomas represent a highly malignant form of mesenchymal tumors. The incidence of synovial sarcomas in the spinal canal is exceptionally rare and has been scarcely reported. Teaching Point: Comprehending the magnetic resonance imaging manifestations of intraspinal synovial sarcoma is important to prevent misdiagnosis.

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