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1.
Diabet Med ; 41(6): e15279, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38185936

RESUMO

AIMS: Evidence is accumulating of the therapeutic benefits of mesenchymal stromal cells (MSCs) in diabetes-related conditions. We have identified a novel population of stromal cells within islets of Langerhans - islet stellate cells (ISCs) - which have a similar morphology to MSCs. In this study we characterize mouse ISCs and compare their morphology and function to MSCs to determine whether ISCs may also have therapeutic potential in diabetes. METHODS: ISCs isolated from mouse islets were compared to mouse bone marrow MSCs by analysis of cell morphology; expression of cell-surface markers and extracellular matrix (ECM) components; proliferation; apoptosis; paracrine activity; and differentiation into adipocytes, chondrocytes and osteocytes. We also assessed the effects of co-culture with ISCs or MSCs on the insulin secretory capacity of islet beta cells. RESULTS: Although morphological similar, ISCs were functionally distinct from MSCs. Thus, ISCs were less proliferative and more apoptotic; they had different expression levels of important paracrine factors; and they were less efficient at differentiation down multiple lineages. Co-culture of mouse islets with ISCs enhanced glucose induced insulin secretion more effectively than co-culture with MSCs. CONCLUSIONS: ISCs are a specific sub-type of islet-derived stromal cells that possess biological behaviors distinct from MSCs. The enhanced beneficial effects of ISCs on islet beta cell function suggests that they may offer a therapeutic target for enhancing beta cell functional survival in diabetes.


Assuntos
Diferenciação Celular , Técnicas de Cocultura , Células Secretoras de Insulina , Ilhotas Pancreáticas , Células-Tronco Mesenquimais , Animais , Camundongos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiologia , Células Secretoras de Insulina/citologia , Diferenciação Celular/fisiologia , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/metabolismo , Células Estreladas do Pâncreas/metabolismo , Células Estreladas do Pâncreas/fisiologia , Proliferação de Células/fisiologia , Insulina/metabolismo , Células Cultivadas , Secreção de Insulina/fisiologia , Camundongos Endogâmicos C57BL , Masculino , Apoptose/fisiologia
2.
Biomacromolecules ; 25(6): 3475-3485, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38741285

RESUMO

Material reinforcement commonly exists in a contradiction between strength and toughness enhancement. Herein, a reinforced strategy through self-assembly is proposed for alginate fibers. Sodium alginate (SA) microstructures with regulated secondary structures are assembled in acidic and ethanol as reinforcing units for alginate fibers. Acidity increases the flexibility of the helix and contributes to enhanced extendibility. Ethanol is responsible for formation of a stiff ß-sheet, which enhances the modulus and strength. The structurally engineered SA assembly exhibits robust mechanical compatibility, and thus reinforced alginate fibers possess an improved tensile strength of 2.1 times, a prolonged elongation of 1.5 times, and an enhanced toughness of 3.0 times compared with SA fibers without reinforcement. The reinforcement through self-assembly provides an understanding of strengthening and toughening mechanism based on secondary structures. Due to a similar modulus with bones, reinforced alginate fibers exhibit good efficacy in accelerating bone regeneration in vivo.


Assuntos
Alginatos , Regeneração Óssea , Resistência à Tração , Alginatos/química , Regeneração Óssea/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Ácido Glucurônico/química , Teste de Materiais , Ácidos Hexurônicos/química , Alicerces Teciduais/química
3.
Cancers (Basel) ; 16(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39061245

RESUMO

Traditional oncology image-analysis, using modalities such as echography, X-ray, CT, and MRI, has historically relied on human-defined features to interpret and assess clinical images [...].

4.
ACS Omega ; 9(2): 2443-2456, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38250349

RESUMO

Coal-based cryptocrystalline graphite is an intermediate phase formed during the transformation of highly metamorphic anthracite into crystalline graphite. In order to explore the relationship between the graphitization degree of coal-based cryptocrystalline graphite and its physical properties from macromolecular structure to provide a theoretical basis for industrial application, samples were tested by X-ray diffraction, electrochemistry, and thermal conductivity and compared with standard graphite (SG) and artificial thermal simulation graphitized samples. The results show that with the increase of graphitization degree and the growth of microcrystalline structure, the electrical impedance of cryptocrystalline graphite decreases, the conductivity increases, the specific capacity of initial discharge increases, and the thermal conductivity increases, which gradually approach the electrical and thermal properties of crystalline graphite. The linear equations between impedance and La and Lc are y = -0.42x + 70.44 and y = -1.87x + 70.62, and the correlation coefficients are 0.93 and 0.88. The linear equations between thermal conductivity and the horizontal extension length (La) and vertical stacking thickness (Lc) are y = 0.09x + 1.36 and y = 0.4x + 0.76, the correlation coefficients are 0.82 and 0.84., and the reduction of microcrystalline parameters d002 and the increase of La and Lc lead to a direct improvement of physical properties. Artificial thermal simulation samples also show the same regularity, but their physical properties are lower than those of natural evolution samples. Short-term high-temperature simulation is different from long-term magma heat and pressure, and the growth of graphite microcrystals is more complete under long-term geological conditions, resulting in better physical properties.

5.
Materials (Basel) ; 17(13)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38998130

RESUMO

The application of alginate fibers is limited by relatively low mechanical properties. Herein, a self-reinforcing strategy inspired by nature is proposed to fabricate alginate fibers with minimal changes in the wet-spinning process. By adapting a coagulation bath composing of CaCl2 and ethanol, the secondary structure of sodium alginate (SA) was regulated during the fibrous formation. Ethanol mainly increased the content of ß-sheet in SA. Rheological analysis revealed a reinforcing mechanism of stiff ß-sheet for enhanced modulus and strength. In combination with Ca2+ crosslinking, the self-reinforced alginate fibers exhibited an increment of 39.0% in tensile strength and 71.9% in toughness. This work provides fundamental understanding for ß-sheet structures in polysaccharides and a subsequent self-reinforcing mechanism. It is significant for synthesizing strong and tough materials. The self-reinforcing strategy involved no extra additives and preserved the degradability of the alginate. The reinforced alginate fibers exhibited promising potentials for biological applications.

6.
Food Sci Nutr ; 12(3): 2104-2114, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38455174

RESUMO

This study (ISRCTN17174559) aimed to explore the efficacy and safety of a kind of herbal porridge (Hou Gu Mi Xi) on the clinical symptoms of functional dyspepsia (FD). This was a single-center, single-dose, prospective, double-blind, randomized controlled trial involving 64 participants with FD (35 cases and 29 controls) for 2 months of intervention and 1 month of follow-up. The 7-point Global Overall Symptom Scale (GOSS), 36-Item Short Form Survey (SF-36), and other indicators were assessed at baseline (day 0), at days 15, 30, and 60 of treatment, and at follow-up 1 month after the end of the intervention. Many participants with FD achieved remission of their epigastric symptoms at follow-up on the 90th day after treatment with herbal porridge compared to the placebo group (45.71% vs. 20.69%, p = .036). Furthermore, herbal porridge appeared to be effective in improving the quality of life of participants with FD, which was reflected in the rising SF-36 scores for physical role, bodily pain, emotional role, and mental health. Although adverse events were reported, there was no overall difference in the number of adverse events between the two groups (p = .578). Herbal porridge is another effective and safe method for improving the symptoms and quality of life in patients with FD.

7.
Postgrad Med ; 136(1): 103-109, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38198583

RESUMO

BACKGROUND: Diabetic foot has a great impact on the life of patients. Its treatment involves a multi-disciplinary and multi-direction approach, which requires not only soft tissue repair, but also bone reconstruction and functional repair. CASE PRESENTATION: A 51-year-old Chinese man with a three-year history of diabetes was diagnosed with ulcers in his left foot. We performed a successful procedure, and the different strategies we adopted helped to avoid serious complications during treatment. The patient was treated with debridement, bone cement, iliac crest graft, and anterolateral femoral skin flap, and recovered well. CONCLUSION: There is a dearth of reports pertaining to treatment of diabetic foot in patients with midfoot bone and soft tissue loss. In this report, we present an effective method that we used to reconstruct the loss of midfoot in a patient with diabetic foot, illustrating a successful therapeutic strategy for saving limbs in this complex medical condition.


Assuntos
Diabetes Mellitus , Pé Diabético , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Masculino , Humanos , Pessoa de Meia-Idade , Pé Diabético/cirurgia , Cicatrização , Ílio/transplante , Retalhos Cirúrgicos/cirurgia
8.
J Phys Chem Lett ; 15(10): 2665-2674, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38426818

RESUMO

The quantum cutting ytterbium (Yb3+)-doped CsPbX3 (X = Cl, Cl, or Br) nanocrystals, exhibiting photoluminescence quantum yields (PLQYs) exceeding 100%, hold significant promise for applications in solar energy conversion technologies and near-infrared (NIR) light-emitting diodes (LEDs). This work investigates the usage of chlorophyll (CHL), a naturally existing organic pigment, as an efficient molecular passivator to improve the performance of quantum cutting films. With the assistance of CHL, the resultant perovskite film displays an increased PLQY of 176%. The commercial silicon solar cells (SSCs) with CHL-treated perovskite films demonstrate a remarkable photon-to-current conversion efficiency improvement of 1.83% for a 330.15 cm2 area SSC device. Additionally, a CHL-modified Yb3+:CsPbCl3 film was used to create 988 nm NIR LEDs with an external quantum efficiency of 3.2%. This work provides a new, eco-friendly approach for producing high-quality, large-area Yb3+-doped perovskite film for deployment in photoelectric and night vision applications.

9.
Heliyon ; 10(5): e27234, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38463812

RESUMO

Cellular immunotherapy is a crucial aspect of current tumor immunotherapy, though it presents several challenges such as immune cell dysfunction, limited recognition of neoantigens, and inadequate lymphocyte infiltration into the tumor microenvironment. This study proposes a novel approach utilizing a combination of dendritic cell (DC)-based cellular immunotherapy and a photothermal nanoadjuvant black phosphorus (BP) nanoparticles to overcome these challenges. A new platform called PLGA@BP-R848, which consists of modifying poly-(lactic-co-glycolic acid) (PLGA) onto BP nanosheets loading the immune adjuvant R848. The PLGA@BP-R848 nanoparticles demonstrated exceptional drug delivery and release capabilities, as well as a photothermal effect, biocompatibility, and the ability to activate the mitochondrial apoptotic pathway Blc-2-Bax-Cytochrome c-caspase-3 and inhibit the PI3K-AKT-mTOR signaling pathway. In a hepatocellular carcinoma mouse model, the binding of PLGA@BP-R848 nanoparticles and dendritic cells primed with GPC3 peptides, successfully induced a systemic anti-tumor immune response. PLGA@BP-R848 nanoparticles bolster immune cell infiltration into tumors and induce cancer cell apoptosis. The synergistic therapy involving dendritic cells and photothermal nanoadjuvant effectively suppressed tumor growth, and facilitated the formation of tertiary lymphatic structures (TLS) in tumors. This study presents a novel approach in using photothermal nanoadjuvants to advance antitumor effect of cellular immunotherapy, such as DCs therapy.

10.
Nat Commun ; 15(1): 5697, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38972900

RESUMO

Climate and environmental changes threaten human mental health, but the impacts of specific environmental conditions on neuropsychiatric disorders remain largely unclear. Here, we show the impact of a humid heat environment on the brain and the gut microbiota using a conditioned housing male mouse model. We demonstrate that a humid heat environment can cause anxiety-like behaviour in male mice. Microbial 16 S rRNA sequencing analysis reveals that a humid heat environment caused gut microbiota dysbiosis (e.g., decreased abundance of Lactobacillus murinus), and metabolomics reveals an increase in serum levels of secondary bile acids (e.g., lithocholic acid). Moreover, increased neuroinflammation is indicated by the elevated expression of proinflammatory cytokines in the serum and cortex, activated PI3K/AKT/NF-κB signalling and a microglial response in the cortex. Strikingly, transplantation of the microbiota from mice reared in a humid heat environment readily recapitulates these abnormalities in germ-free mice, and these abnormalities are markedly reversed by Lactobacillus murinus administration. Human samples collected during the humid heat season also show a decrease in Lactobacillus murinus abundance and an increase in the serum lithocholic acid concentration. In conclusion, gut microbiota dysbiosis induced by a humid heat environment drives the progression of anxiety disorders by impairing bile acid metabolism and enhancing neuroinflammation, and probiotic administration is a potential therapeutic strategy for these disorders.


Assuntos
Ansiedade , Ácidos e Sais Biliares , Disbiose , Microbioma Gastrointestinal , Temperatura Alta , Animais , Masculino , Camundongos , Ácidos e Sais Biliares/metabolismo , Humanos , Disbiose/microbiologia , Ansiedade/microbiologia , Camundongos Endogâmicos C57BL , Umidade , Ácido Litocólico/metabolismo , Lactobacillus , Encéfalo/metabolismo , NF-kappa B/metabolismo , RNA Ribossômico 16S/genética , Modelos Animais de Doenças , Transtornos de Ansiedade/metabolismo , Transtornos de Ansiedade/microbiologia , Transtornos de Ansiedade/etiologia , Transdução de Sinais , Citocinas/metabolismo
11.
Comput Struct Biotechnol J ; 23: 2122-2131, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38817963

RESUMO

B-cell epitope identification plays a vital role in the development of vaccines, therapies, and diagnostic tools. Currently, molecular docking tools in B-cell epitope prediction are heavily influenced by empirical parameters and require significant computational resources, rendering a great challenge to meet large-scale prediction demands. When predicting epitopes from antigen-antibody complex, current artificial intelligence algorithms cannot accurately implement the prediction due to insufficient protein feature representations, indicating novel algorithm is desperately needed for efficient protein information extraction. In this paper, we introduce a multimodal model called WUREN (Whole-modal Union Representation for Epitope predictioN), which effectively combines sequence, graph, and structural features. It achieved AUC-PR scores of 0.213 and 0.193 on the solved structures and AlphaFold-generated structures, respectively, for the independent test proteins selected from DiscoTope3 benchmark. Our findings indicate that WUREN is an efficient feature extraction model for protein complexes, with the generalizable application potential in the development of protein-based drugs. Moreover, the streamlined framework of WUREN could be readily extended to model similar biomolecules, such as nucleic acids, carbohydrates, and lipids.

12.
Clin Case Rep ; 12(2): e8453, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38292225

RESUMO

AlphaMissense is proficient in predicting the clinical classification of missense variants. we utilized AlphaMissense to find disease-relevant variants within a polymicrobial pulmonary infection case. Exome sequencing was performed in this patient, and AlphaMissense and Phenolyzer were combined to investigate disease-relevant variants screening from exome sequencing results.

13.
Nat Commun ; 15(1): 1947, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431630

RESUMO

Cellular responses to the steroid hormones, estrogen (E2), and progesterone (P4) are governed by their cognate receptor's transcriptional output. However, the feed-forward mechanisms that shape cell-type-specific transcriptional fulcrums for steroid receptors are unidentified. Herein, we found that a common feed-forward mechanism between GREB1 and steroid receptors regulates the differential effect of GREB1 on steroid hormones in a physiological or pathological context. In physiological (receptive) endometrium, GREB1 controls P4-responses in uterine stroma, affecting endometrial receptivity and decidualization, while not affecting E2-mediated epithelial proliferation. Of mechanism, progesterone-induced GREB1 physically interacts with the progesterone receptor, acting as a cofactor in a positive feedback mechanism to regulate P4-responsive genes. Conversely, in endometrial pathology (endometriosis), E2-induced GREB1 modulates E2-dependent gene expression to promote the growth of endometriotic lesions in mice. This differential action of GREB1 exerted by a common feed-forward mechanism with steroid receptors advances our understanding of mechanisms that underlie cell- and tissue-specific steroid hormone actions.


Assuntos
Endometriose , Proteínas de Neoplasias , Receptores de Esteroides , Animais , Feminino , Humanos , Camundongos , Endometriose/genética , Endometriose/metabolismo , Endométrio/metabolismo , Estrogênios/metabolismo , Proteínas de Neoplasias/metabolismo , Progesterona/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Esteroides/metabolismo
14.
Front Pharmacol ; 14: 1287750, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259291

RESUMO

Background: Recently, multiple preclinical studies have reported the beneficial effect of berberine in the treatment of Alzheimer's disease (AD). Nevertheless, the neuroprotective effects and possible mechanisms of berberine against AD are not universally recognized. This study aimed to conduct a systematic review and meta-analysis by integrating relevant animal studies to assess the neuroprotective effects and potential mechanisms of berberine on AD. Methods: We systematically searched PubMed, Embase, Scopus and Web of Science databases that reported the effects of berberine on AD models up to 1 February 2023. The escape latency, times of crossing platform, time spent in the target quadrant and pro-oligomerized amyloid beta 42 (Aß1-42) were included as primary outcomes. The secondary outcomes were the Tau-ps 204, Tau-ps 404, ß-site of APP cleaving enzyme (BACE1), amyloid precursor protein (APP), acetylcholine esterase (AChE), tumor necrosis factor ⍺ (TNF-α), interleukin 1ß (IL-1ß), IL-6, nitric oxide (NO), glial fibrillary acidic protein (GFAP), malonaldehyde (MDA), glutathione S-transferase (GST), glutathione (GSH), glutathione peroxidase (GPx), Beclin-1 and neuronal apoptosis cells. This meta-analysis was conducted using RevMan 5.4 and STATA 15.1. The SYRCLE's risk of bias tool was used to assess the methodological quality. Results: Twenty-two studies and 453 animals were included in the analysis. The overall results showed that berberine significantly shortened the escape latency (p < 0.00001), increased times of crossing platform (p < 0.00001) and time spent in the target quadrant (p < 0.00001), decreased Aß1-42 deposition (p < 0.00001), Tau-ps 202 (p < 0.00001) and Tau-ps 404 (p = 0.002), and improved BACE1, APP, AChE, Beclin-1, neuronal apoptosis cells, oxidative stress and inflammation levels. Conclusion: Berberine may be a promising drug for the treatment of AD based on preclinical evidence (especially when the dose was 5-260 mg/kg). The potential mechanisms for these protective effects may be closely related to anti-neuroinflammation, anti-oxidative stress, modulation of autophagy, inhibition of neuronal apoptosis and protection of cholinergic system. However, these results may be limited by the quality of existing research. Larger and methodologically more rigorous preclinical research are needed to provide more convincing evidence.

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