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1.
ACS Appl Mater Interfaces ; 15(3): 4668-4676, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36640109

RESUMO

The host-guest interaction between hexamethyl cucurbit[5]uril (HmeQ[5]) and 1,4-diaminobenzene (DB) was investigated, and a new low-molecular-weight supramolecular gel was prepared by a simple heating/mixing cooling method. The structure and properties of the supramolecular gel were characterized. Results revealed that DB molecules did not enter the cavity of HmeQ[5] and that hydrogen bonding between the carbonyl group at the HmeQ[5] port and the DB amino groups, together with dipole-dipole interactions and outer wall interactions, were the main driving forces for the formation of the supramolecular gel. The HmeQ[5]/DB gel system exhibits temperature sensitivity. The phosphor 6-bromo-2-naphthol (BrNp) was embedded in the gel to give the gel fluorescent phosphorescence double emission. The double emission ability at room temperature can be attributed to the ordered microstructure of the supramolecular gel, which effectively avoids the nonradiative transition of BrNp. Meanwhile, HmeQ[5]/DB-BrNp has good biocompatibility and low biotoxicity, which is compatible with HeLa cells to achieve cytoplasmic staining of HeLa in the red channel. The supramolecular gels constructed by this supramolecular assembly strategy not only have good temperature sensitivity but also extend the application of Q[n]s in biomedical fields.


Assuntos
Hidrogéis , Naftóis , Humanos , Hidrogéis/química , Temperatura , Células HeLa
2.
Health Commun ; : 1-16, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36693813

RESUMO

Touch is a fundamental resource mobilized by clinicians in physical examinations in outpatient clinical consultations. However, few studies have been conducted to explore the sequential organization of touch in the interactional process of physical examinations where clinicians' touch is launched and responded to in Chinese medical settings. Based on a collection of video recordings of naturally occurring clinician-patient interaction in an orthopedic outpatient clinic in China, we observed four types of clinicians' touch in the physical examination framework: the guiding touch, the diagnostic touch, the demonstrative touch, and the therapeutic touch. Together with clinical expertise, the sensorial knowledge obtained through touch enables clinicians to professionally evaluate patients' physical conditions and diagnose their illnesses. We also demonstrated that patients do not merely put themselves into clinicians' hands as clinical objects for inspection and defer to clinicians' medical authority. Instead, they actively and agentively participate in physical examinations to jointly accomplish social actions and activities through the temporal and sequential mobilization of their multimodal resources. This study not only adds to an emerging body of research on touch in medical settings but also sheds some light on the understanding of the clinician-patient interaction in Chinese outpatient clinics.

3.
J Org Chem ; 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36701768

RESUMO

An efficient and practical SO2 insertion protocol of NH-sulfoximines with aryldiazonium tetrafluoroborates and DABSO toward N-sulfonyl sulfoximines has been developed under mildly basic conditions. This transformation features easy operation, readily available substrates, and mild conditions. A tentative mechanism is proposed, which indicates that the aryldiazonium tetrafluoroborates would be radical donors under standard reaction conditions. The aryl radical produced in situ from diazonium salts would be trapped by SO2 to generate an arylsulfonyl radical and then undergo further transformation to generate the final N-sulfonyl sulfoximines.

4.
Leuk Lymphoma ; : 1-12, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36657437

RESUMO

THZ1, a CDK7 inhibitor, has potent antitumor effects in several cancers; however, its role in Acute myeloid leukemia (AML) is unclear. We explored the effects and potential mechanisms of THZ1, alone and in combination with azacitidine (AZA), in AML cells and xenograft models. THZ1 decreased cell viability, induced apoptosis in a dose and time-dependent manner, induced G0/G1 cell cycle arrest, decreased phosphorylated CDK1 and CDK2 expression, and inhibited RNA Pol II phosphorylation at multiple serine sites. The combination of AZA and THZ1 exhibited synergistic antileukemic effects in AML cell lines and primary cells with MCL1 and c-MYC downregulation. Moreover, the combination therapy significantly decreased tumor burden and prolonged animal survival in xenograft mice models. Our data demonstrate that CDK7 inhibition induces the apoptosis of AML cells and exerts a synergistic antileukemia effect with AZA in vitro and in vivo, which supports future exploration of this combination in clinical studies.

5.
Gastrointest Endosc ; 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36657608

RESUMO

BACKGROUND AND AIMS: Treatment strategies for early cancers or precancerous lesions of the upper gastrointestinal tract in cirrhotic patients with esophagogastric varices (EGV) are complicated and risky. We aimed to assess the efficacy and safety of endoscopic submucosal dissection (ESD) in the treatment of such patients and explore optimal treatment strategies. METHODS: We retrospectively enrolled 15 cirrhotic patients with EGV who underwent ESD for early cancers or precancerous lesions of the upper gastrointestinal tract from January 2012 to December 2021 at our center. Clinical features, endoscopic findings, treatment methods, adverse events and follow-up data were analyzed. RESULTS: Of the 15 patients, 1 had a platelet count <30×1000/mm3. Five were untreated for EGV, 1 was treated after ESD, 6 were treated before ESD, 1 was treated before and during ESD, and 2 were treated during ESD. The R0 resection rate was 100%. Of the 16 mucosal lesions, 15 were ERB-0 or ERB-c1, and 1 was ERB-c2. No patient experienced deterioration in liver function. The only adverse events were fever in 2 patients and postoperative bleeding (PB) in 2 patients. During a median follow-up of 27 months, 1 patient's esophageal HGD recurred at 19 months. No death resulted from the ESD procedure, liver function injury or gastrointestinal tumor itself. CONCLUSION: ESD is an effective and safe treatment for early cancers or precancerous lesions of the upper gastrointestinal tract in cirrhotic patients with EGV. The incidence of severe adverse events is very low due to the development of individualized clinical treatment strategies.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36658675

RESUMO

AIM: To study the safety and efficacy of anlotinib, a multitargeted tyrosine kinase inhibitor, in the treatment of advanced osteosarcoma (OSS) with metastases. METHODS: We retrospectively studied patients with advanced OSS and metastases who received anlotinib treatment in our hospital from June 2018 to April 2020. All patients had received standard multimodal therapies, before taking anlotinib. Therapeutic doses of anlotinib were 12 mg for adults and 10 mg for children and adolescents once a day for 2 consecutive weeks, followed by a week of withdrawal. This 3-week cycle of treatment was continued until the tumor progressed rapidly or the patients failed to tolerate the side effects. Adverse drug reactions were recorded, and therapeutic efficacy was evaluated based on progression-free survival (PFS), disease control rate (DCR), overall survival (OS), and objective response rate (ORR). RESULTS: The median PFS was 9.8 ± .9 months, and the 6- and 10-month PFS rates were 73% and 33%, respectively. The median OS was 11.4 ± .6 months. No patients achieved complete response. After 6 months of treatment, the DCR and ORR were 80% and 13%, respectively. No drug-related deaths or Grade 4 adverse events occurred in the patients. Five patients (33%) had Grade 3 adverse events. The most common drug-related adverse events were hand-food syndrome, fatigue, high blood pressure, anorexia, and pneumothorax. CONCLUSIONS: Anlotinib had a modest therapeutic effect in patients with advanced OSS after the failure of standard treatment. The adverse events were mostly tolerable or relieved after treatment.

7.
Angew Chem Int Ed Engl ; : e202215074, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658744

RESUMO

White et al., in a recent Correspondence, provided additional structural data to illustrate that CPOS-6 undergoes a single-crystal-to-single-crystal transformation during water adsorption/desorption. This finding gave a better understanding of the relevant experimental phenomena from the perspective of structural transformation and is a good complement to our previous results. However, we wish to emphasize that our research focuses on the kinetic behavior of water during ultrafast adsorption/desorption in nano-confined channels. Herein, we further interpret the rapid transport of water molecules in the nano-confined channels from the perspective of superfluidity.

8.
Langmuir ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36661856

RESUMO

Slippery silicone-oil-infused (SOI) surfaces have recently emerged as a promising alternative to conventional anti-infection coatings for urinary catheters to combat biofilm and encrustation formation. Benefiting from the ultralow low hysteresis and slippery behavior, the liquid-like SOI coatings have been found to effectively reduce bacterial adhesion under both static and flow conditions. However, in real clinical settings, the use of catheters may also trigger local inflammation, leading to release of host-secreted proteins, such as fibrinogen (Fgn) that deposits on the catheter surfaces, creating a niche that can be exploited by uropathogens to cause infections. In this work, we report on the fabrication of a silicone oil-infused silver-releasing catheter which exhibited superior durability and robust antibacterial activity in aqueous conditions, reducing biofilm formation of two key uropathogens Escherichia coli and Proteus mirabilis by ∼99%, when compared with commercial all-silicone catheters after 7 days while remaining noncytotoxic toward L929 mouse fibroblasts. After exposure to Fgn, the oil-infused surfaces induced conformational changes in the protein which accelerated adsorption onto the surfaces. The deposited Fgn blocked the interaction of silver with the bacteria and served as a scaffold, which promoted bacterial colonization, resulting in a compromised antibiofilm activity. Fgn binding also facilitated the migration of Proteus mirabilis over the catheter surfaces and accelerated the deposition and spread of crystalline biofilm. Our findings suggest that the use of silicone oil-infused silver-releasing urinary catheters may not be a feasible strategy to combat infections and associated complications arising from severe inflammation.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36692718

RESUMO

There is evidence that perfluoroalkyl substances (PFASs) have effects on liver toxicity, and the effects may exhibit sex differences. Our study aims to explore the association between exposure to four PFASs (perfluorooctanoic acid, PFOA; perfluorooctane sulfonate, PFOS; perfluorohexane sulfonate, PFHxS; and perfluorononanoate, PFNA) and the risk of nonalcoholic fatty liver disease (NAFLD) in adults ≥ 20 years old in the US population. The data were based on the National Health and Nutrition Examination Survey (NHANES) 2005-2018. We used Poisson regression to explore the association between the four PFASs and NAFLD. We included 3464 participants; of these, 1200 (34.64%) individuals were defined as having NAFLD, and the prevalence of NAFLD was 39.52% in men and 30.40% in women. After Poisson regression, among the premenopausal and postmenopausal and total women, PFOA had a significantly positive association with NAFLD (p < 0.05). After principal component analysis, the "composite PFAS" was associated with NAFLD in postmenopausal and total women, and the RRs (95% CIs) were 1.306 (1.075, 1.586) and 1.161 (1.007, 1.339), respectively. In adults, we found that PFASs were associated with NAFLD, and the associations varied by sex, particularly for PFOA and PFNA, which had a positive association with NAFLD in women.

10.
Environ Technol ; : 1-22, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36609215

RESUMO

We propose a feasible and economical method of constructing biomass-based multifunctional photocatalysts with excellent adsorption performance and high photodegradation abilities toward tetracycline (TC) and methyl blue (MB) under visible light. A series of novel hybrids of porous graphitic carbon embedded with Fe2O3/Fe3O4 nanocrystals (denoted as Fe2O3/Fe3O4@C) were derived from lichen doped with different dosages of Fe3+ by calcination at 700°C under a N2 atmosphere. The Fe2O3/Fe3O4@C hybrids exhibited nanoflake-like shapes, mesoporous structures, and efficient visible light harvesting, thus indicating enhanced adsorption ability and photoactivity toward pollutants. The formed Fe2O3/Fe3O4 heterojunction improved the separation efficiency and inhibited the recombination of photogenerated carriers, whereas the carbon network improved the transfer of photogenerated electrons. Under optimised conditions, the Fe2O3/Fe3O4@C-1 hybrid demonstrated enhanced photodegradation efficiencies of 96.4% for TC and 100% for MB under visible light. In addition, electron spin resonance and trapping measurements were performed to identify active species and determine the photocatalytic mechanism toward pollutants. •O2- and •OH were the active species involved, playing critical roles in the TC and MB photodegradation processes. In addition, a bacterium test revealed that the products of TC degradation by Fe2O3/Fe3O4@C-1 showed low biological toxicity. This work provides a promising preparation strategy or biomass-based photocatalysts for application in environmental pollutant treatment.

11.
Nanoscale ; 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36598754

RESUMO

Tin dioxide (SnO2) with a high theoretical capacity of 1494 mA h g-1 has great potential to break through the capacity limitation of the conventional graphite anode (372 mA h g-1) in lithium-ion batteries. However, its practical application still faces several obstacles such as high volumetric expansion and poor electrical conductivity. To solve these problems, innovative design and synthesis of SnO2-based nanocomposite structures are necessary. Herein, we demonstrate an integrated design of a hierarchical pitaya-like P-SnO2/C@NC core-shell nanostructure which includes the core of SnO2 nanoparticles (∼4-12 nm) uniformly embedded in the porous carbon sphere and the shell of a continuous nitrogen-doped carbon (NC) layer. Specifically, during repetitive lithiation and delithiation processes, the ultrasmall SnO2 nanoparticles reduce the internal stress greatly, the porous carbon matrix provides buffer space for a large volume change, and the N-doped carbon shell further guarantees the whole structure unit sufficient electrical conductivity and structural stability. Consequently, the resultant battery exhibits a reversible capacity of 936.8 mA h g-1 after 100 cycles at 100 mA g-1 and even an average capacity of 460.0 mA h g-1 at a high current density of 3.2 A g-1. The excellent electrochemical performance of pitaya-like SnO2/C@NC proves the efficacy of this structure design and thus provides significant reference for the construction of other electrode materials in rechargeable alkali metal ion batteries.

12.
J Cell Mol Med ; 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36651490

RESUMO

Among breast cancer patients, metastases are the leading cause of death. Despite decades of effort, little progress has been made to improve the treatment of breast cancer metastases, especially triple-negative breast cancer (TNBC). The extracellular matrix plays an important role in tumour growth and metastasis by causing its deposition, remodelling, and signalling. As we know, the process of fibrosis results in excessive amounts of extracellular matrix being deposited within the cells. So, it will be interesting to study if the use of anti-fibrotic drugs in combination with conventional chemotherapy drugs can produce synergistic antitumor effects. In this study, we assessed the efficacy of Pirfenidone (PFD), an FDA-approved medication for the treatment of idiopathic pulmonary fibrosis, on TNBC cells as well as its anti-tumour effects in xenograft tumour model. PFD inhibited in a dose-dependent manner breast cancer cell proliferation, migration, and invasion, while promoted their apoptosis in vitro. PFD also suppressed TGF-ß-induced activation of Smad signalling pathway and expression level of EMT-inducing transcription factors (e.g. SNAI2, TWIST1, ZEB1) as well as the mesenchymal genes such as VIMENTIN and N-Cadherin. On the contrary, the expression level of epithelial marker gene E-Cadherin was up-regulated in the presence of PFD. In vivo, PFD alone exerted a milder but significant anti-tumour effect than the chemotherapy drug nanoparticle albumin-bound paclitaxel (nab-PTX) did in the breast cancer xenograft mouse model. Interestingly, PFD synergistically boosted the cancer-killing effect of nab-PTX. Furthermore, Our data suggest that PFD suppressed breast cancer metastasis by inhibiting the activity of the TGFß/SMAD pathway.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36652328

RESUMO

All-polymer solar cells (all-PSCs) have been widely studied owing to their unique mechanical flexibility and stability. However, all-PSCs have a lower efficiency than small-molecule acceptor-based PSCs. In the work, a ternary quasi-all-polymer solar cell (Q-all-PSC) using a synergy of the ternary strategy and solid additive engineering is reported. The introduction of PC71BM can not only match the energy level of the photoactive materials with an improved open circuit voltage (VOC) of the ternary devices but also enhance photon capture, which can improve short circuit current density. It is found that there is effective charge transfer between PC71BM and PY-IT, which can form an electron transport channel and promote efficient charge transport. Moreover, the introduction of PC71BM made the PM6/PY-IT/PC71BM ternary blends more crystalline while slightly reducing phase separation, resulting in a suitable domain size. Importantly, by introducing a high dielectric-constant PFBEK solid additive as the fasten matrix, the Q-all-PSC's efficiency can reach 16.42%. This method provides a new idea for future research on all-polymer solar cells.

14.
Physiol Plant ; : e13853, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36628625

RESUMO

The AP2/ERF family is an important class of transcription factors involved in plant growth and various biological processes. One of the AP2/ERF transcription factors, RAP2.6L, participates in various stresses responses. However, the function of RAP2.6L is largely unknown in apples (Malus domestica). In this study, an apple gene homologous to Arabidopsis AtRAP2.6L, MdERF113, was analyzed by bioinformatic characterization, gene expression analysis and subcellular localization assessment. MdERF113 was highly expressed in the sarcocarp and was responsive to hormonal signals and abiotic stresses. MdERF113-overexpression apple calli were less sensitive to low temperature, drought, salinity, and abscisic acid than wild-type. Subcellular localization revealed that MdERF113 was a nuclear-localized transcription factor, and yeast experiments confirmed that MdERF113 has no autonomous activation activity. Overall, this study indicated that MdERF113 palys a role in regulating plant growth under abiotic conditions.

15.
BMC Musculoskelet Disord ; 24(1): 12, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609247

RESUMO

BACKGROUND: To determine the volume and applicability of local autogenous morselized bone (LAMB) harvested and used during posterior-transforaminal lumbar interbody fusion (P-TLIF) in the lower lumbar spine. METHODS: Clinical and radiographic data of 147 patients (87 males) undergoing P-TLIF from January 2017 to December 2019 for lumbar degenerative diseases were retrospectively analyzed. Computed tomography was used to assess the fusion status (at 6 months, 1 year, and the last follow-up postoperatively), restored disc height, graft fusion area and volume, and the minimum required bone volume (MRBV). Clinical outcomes of P-TLIF were assessed using the Oswestry Disability Index (ODI) and visual analog scale (VAS) for low back pain (LBP) and leg pain (LP). RESULTS: The mean follow-up period was 28.4 ± 4.49 months. The patient's age and diagnosis were correlated to the volume and weight of LAMB (mean volume and weight: 3.50 ± 0.45 mL and 3.88 ± 0.47 g, respectively). The ratio of actual fusion area to the total disc endplate and the ratio of actual fusion volume to the total volume of the disc space were > 40%. MRBV ranged from 1.83 ± 0.48 cm3 to 2.97 ± 0.68 cm3. The proportion of grade 4 or 5 fusions increased from 60.6% at 6 months to 96.6% at the last follow-up. The ODI, VAS-LP, and VAS-LBP scores significantly improved after surgery and remained unchanged during the follow-up. CONCLUSION: When combined with a cage, the volume of LAMB harvested from decompression through the unilateral approach at a single-level is sufficient to achieve a solid interbody fusion in the lower lumbar spine with excellent clinical and radiographic outcomes.


Assuntos
Dor Lombar , Fusão Vertebral , Masculino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Estudos Retrospectivos , Região Lombossacral/cirurgia , Dor Lombar/diagnóstico por imagem , Dor Lombar/etiologia , Dor Lombar/cirurgia , Descompressão , Resultado do Tratamento , Procedimentos Cirúrgicos Minimamente Invasivos/métodos
16.
Neurobiol Dis ; 177: 105993, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36627028

RESUMO

Clarifying the risk factors and mechanisms that contribute to the onset of cognitive impairment following estrogen depletion is essential for improving the quality of life of older females. In the current study, using behavioral tests, 16S rDNA sequencing, in vivo and in vitro electrophysiology, optogenetics and chemogenetics, we found that high-fat diet (HFD)-accelerated impairment of hippocampus-dependent memory, gut microbiota, and hippocampal theta rhythmogenesis in ovariectomized (OVX) mice and fecal microbiota transplantation rescued these phenomena. The identification of fasting-activated medial septal neurons showed that PV+ GABAergic neurons in the medial septal area (MSA) respond to gut sensory signals. Optogenetic activation of septohippocampal PV+ GABAergic fibers (but not cholinergic fibers) significantly rescued hippocampal theta rhythmogenesis and spatial memory in HFD-fed OVX mice. Resistant starch supplementation (RSHFD) rectified the gut Prevotellaceae and considerably alleviated reduced septal gut-responsive neurons, decreased hippocampal theta rhythm, and impaired hippocampus-dependent memory in HFD-fed OVX mice. Furthermore, chemogenetic inhibition of septal PV+ GABAergic neurons reversed the neuroprotective effects of resistant starch supplementation. These findings highlight the notable gut-sensory nature of medial septal PV+ GABAergic neurons. A HFD accelerates estrogen deficiency-induced cognitive impairment by disrupting the gut Prevotellaceae-septo-hippocampal pathway. This study contributes to a better understanding of the precise gut-brain control of cognition and cognitive impairment in postmenopausal females.

17.
Mol Neurobiol ; 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689133

RESUMO

Stabilizing and inhibiting plaque formation is a key challenge for preventing and treating ischemic stroke. KDM1A-mediated histone modifications, which involved in the development of training immunity, ultimately exacerbate the outcomes of inflammation. Although lncRNAs can recruit KDM1A to participate in histone methylation modification and regulate inflammation, cell proliferation, and other biological processes, little is known about the role of KDM1A-lncRNA interaction during atherosclerosis. The present study sought to delineate the effect of the interaction between lnc_000048 and KDM1A on plaque rupture in carotid atherosclerosis, as well as the potential mechanism. Our results revealed that lnc_000048 reduced the activity of histone demethylase and activated MAP2K2 expression by interacting with KDM1A. Furthermore, upregulated lnc_000048 indirectly regulated ERK phosphorylation by MAP2K2 and eventually activated the inflammatory response through the MAPK pathway, which was involved in atherosclerosis. Importantly, our study using ApoE-/- mice confirmed the regulatory role of lnc_000048 in promoting inflammation and collagen degradation in atherosclerotic plaques. These results suggest that targeting the lnc_000048 /KDM1A/MAP2K2/ERK axis may be a promising strategy for preventing atherosclerosis.

18.
Vet Microbiol ; 277: 109620, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36543090

RESUMO

Since March 2021, an infectious characterized by white necrotic foci throughout the goose body has appeared in the major goose-producing regions in China. This disease has caused economic hardship for goose farms in many regions of China with approximately 50 % mortality. A novel goose-origin orthoreovirus was isolated from the spleen of diseased geese and designated as N-GRV/HN/Goose/2021/China (N-GRV-HN21) strain. Next-generation sequencing and phylogenetic analysis revealed that the isolate was a reassortant virus containing viral gene segments from three ARV serotypes that infect duck, muscovy duck, and goose. Geese infection test showed that both N-GRV-HN21-infected and contacted geese displayed whole-body white necrotic foci. N-GRV RNA was detected in different organs of both infected and contacted geese, indicating that the N-GRV isolate is pathogenic and transmissible in geese. Seroconversion was also observed in experimentally infected and contacted geese. A prevalence study of 323 goose serum samples collected from different goose breeding areas showed that 86 % of the geese were positive for N-GRV. In conclusion, all results warrant the necessity to monitor orthoreovirus epidemiology and reassortment as the orthoreovirus could be an important pathogen for the waterfowl industry and a novel orthoreovirus might emerge to threaten animal and public health.


Assuntos
Orthoreovirus Aviário , Orthoreovirus , Doenças das Aves Domésticas , Infecções por Reoviridae , Animais , Orthoreovirus/genética , Filogenia , Virulência , Infecções por Reoviridae/epidemiologia , Infecções por Reoviridae/veterinária , China/epidemiologia , Necrose/veterinária , Patos , Recombinação Genética , Gansos , Doenças das Aves Domésticas/epidemiologia
19.
Acta Biomater ; 157: 297-309, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36543279

RESUMO

Studies on the interaction between cells and micromanipulation tools are necessary to optimize the procedures and improve the developmental potential of cells. The molecular dynamics simulation is not possible for such a large-scale simulation, and the spring-damped viscoelastic models and the constitutive equations of the continuum are usually adopted to model the cells as a whole without consideration of the different properties presented by the heterogeneous subcellular components. In this study, we utilized coarse-grained modeling to develop a subcellular model of suspension cell dynamics and a model of a holding micropipette for the fixation of a suspension cell, and designed a large-scale, accurate mesoscopic simulation environment for specific cell micromanipulation. We established a triangular mesh cell membrane and a uniformly distributed, non-intersecting cytoskeleton network and added polymerization/depolymerization processes to connect the cytoskeleton chains with the membrane and cross-linking proteins. In the cell aspiration model, we adopted the profile of the reversed Poiseuille flow to calibrate the viscosity of the fluid and set the bounce-back condition and the appropriate solid-fluid force coefficient to realize non-slip flow at the boundary. The rheological properties of the cells during micropipette aspiration were further analyzed in the simulation by varying parameters such as the inner diameter of the micropipette, negative pressure, and maximum bond length. The model well reproduced the experimentally observed cell deformation phenomenon at low and high pressures. The dynamic response of the cell elongation observed from the simulation was consistent with that obtained from the analysis of the experimental data collected from a custom-designed micromanipulation system. STATEMENT OF SIGNIFICANCE: In this study, we extended the coarse-grained modeling of cells by developing a relatively large-scale micromanipulation environment consisting of a subcellular cell dynamics model and a fluid flow model for cell aspiration. We simulated cytoskeleton filaments that were uniformly distributed in space via applying Harmonic energy to model cytoskeleton with a high level of fidelity. The shortcoming of the soft repulsion in the solid-fluid interaction in the current simulation technique was solved by implementing the bounce-back boundary and the condition that the total force imposed by the wall particles on the fluid particles was equal to the pressure of the fluid. This work paved the way for understanding the mechanical properties of cells and improving the biological efficacy of micromanipulation.

20.
Neurosci Lett ; 796: 137017, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36529387

RESUMO

BACKGROUND: Exosomes bind to and are endocytosed by neurons of various brain regions. Methods for isolating and extracting exosomes from specific brain samples are critical. At present, the most important extractive methods for exosomes are Ultracentrifugation and exosome isolation kit extraction. Both of these extraction methods have applications in neuroscience. We compare these methods to reveal the differences. METHODS: We sectioned the nucleus accumbens of mice, and isolated exosomes. A culture medium containing exosomes was extracted using ultracentrifugation (UC) and a total exosome isolation kit (TEI). The exosomes were examined using transmission electron microscopy (TEM), measurement regarding the diameter of the exosomes was done, and the thermal allodynia and western blotting analysis were also conducted, respectively. RESULTS: Transmission electron microscopy observations showed that the ultracentrifugation samples had higher purity and fewer impurities than the kit samples. The results from the two methods were then compared with a number ratio regarding the percentage was not statistically significant. Marker protein tests showed that proteins were expressed under both methods. The thermal allodynia testing observed that the two extraction methods did not affect pain behavior regarding the detection. After the kit extraction method, there were substantial white subjects suspended by PBS. CONCLUSION: Our study compared the different protocols regarding exosome extraction from the nucleus accumbens and compared the quality of two principal methods for exosome extraction from a culture medium containing exosomes. It was found that the extraction quality of exosomes by ultracentrifugation was better, but the technical difficulty was greater.


Assuntos
Exossomos , Camundongos , Animais , Exossomos/metabolismo , Núcleo Accumbens/metabolismo , Hiperalgesia/metabolismo , Proteínas/metabolismo , Meios de Cultura
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