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1.
PLoS One ; 18(12): e0295432, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38060514

RESUMO

Pain is strongly associated with neuro-immune activation. Thus, the emerging role of the endocannabinoid system in neuro-inflammation is important. Acupuncture has been used for over 2500 years and is widely accepted for the management of pain. Our study aimed to investigate the effects of electroacupuncture on the regulation of cannabinoid receptor type 1 within the peripheral nervous system. Inflammatory pain was induced by injecting Complete Freund's adjuvant to induce mechanical and thermal hyperalgesia. Electroacupuncture significantly attenuated the mechanical and thermal sensitivities, and AM251, a cannabinoid receptor type 1 antagonist, eliminated these effects. Dual immunofluorescence staining demonstrated that electroacupuncture elevated expression of cannabinoid receptor type 1, co-localized with Nav 1.8. Furthermore, electroacupuncture significantly reduced levels of Nav 1.8 and COX-2 by western blot analysis, but not vice versa as AM251 treatment. Our data indicate that electroacupuncture mediates antinociceptive effects through peripheral endocannabinoid system signaling pathway and provide evidence that electroacupuncture is beneficial for pain treatment.


Assuntos
Eletroacupuntura , Endocanabinoides , Ratos , Camundongos , Animais , Ratos Sprague-Dawley , Dor/metabolismo , Hiperalgesia/metabolismo , Transdução de Sinais , Receptores de Canabinoides , Inflamação/metabolismo
2.
Medicine (Baltimore) ; 102(13): e33341, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37000047

RESUMO

INTRODUCTION: This systematic review and meta-analysis aimed to assess the efficacy and safety of cupping therapy in patients with metabolic syndrome (MetS). METHODS: This systematic review focused on patients with MetS and included randomized controlled trials (RCTs) that compared the effects of cupping therapy with control groups. A total of 12 electronic databases were searched from inception until February 03, 2023. The main outcome after the meta-analysis was waist circumference; the others included anthropometric variables, blood pressure, lipid profile, fasting blood glucose level, and high-sensitivity C-reactive protein level. The incidence of adverse events and the follow-up courses were also evaluated. Risk of bias (ROB) was evaluated using ROB 2.0 from the Cochrane Handbook. RESULTS: This systematic review included five studies involving 489 patients. Some risks of bias were also identified. The meta-analysis revealed a statistically significance in waist circumference (MD = -6.07, 95% CI: -8.44 to -3.71, P < .001, I2 = 61%, τ2 = 3.4), body weight (MD = -2.46, 95% CI: -4.25 to -0.68, P = .007, I2 = 0%, τ2 = 0) and body mass index (MD = -1.26, 95% CI: -2.11 to -0.40, P = .004, I2 = 0%, τ2 = 0) between the cupping therapy and control groups. However, there were no significant results in total fat percentage and blood pressure values. Regarding biochemical markers, cupping significantly lowered the concentration of low-density lipoprotein cholesterol (MD = -3.98, 95% CI: -6.99 to -0.96, P = .010, I2 = 0%, τ2 = 0) but had no significant effect on total cholesterol, triglyceride, high-density lipoprotein cholesterol, fasting blood glucose, and high-sensitivity C-reactive protein. 3 RCTs reported no adverse events. CONCLUSIONS: Despite some ROB and low to substantial heterogeneity of the included studies, cupping therapy can be considered a safe and effective complementary intervention for reducing waist circumference, body weight, body mass index, and low-density lipoprotein cholesterol in patients with MetS. In the future, well-designed, high-quality, rigorous methodology, and long-term RCTs in this population are required to assess the efficacy and safety of cupping therapy.


Assuntos
Síndrome Metabólica , Humanos , Síndrome Metabólica/terapia , Glicemia , Proteína C-Reativa , Peso Corporal , Lipoproteínas LDL , Colesterol
3.
Adv Healthc Mater ; 12(8): e2201708, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36455286

RESUMO

The intricate functionalities of cellular membranes have inspired strategies for deriving and anchoring cell-surface components onto solid substrates for biological studies, biosensor applications, and tissue engineering. However, introducing conformal and right-side-out cell membrane coverage onto planar substrates requires cumbersome protocols susceptible to significant device-to-device variability. Here, a facile approach for biomembrane functionalization of planar substrates is demonstrated by subjecting confluent cellular monolayer to intracellular hydrogel polymerization. The resulting cell-gel hybrid, herein termed GELL (gelated cell), exhibits extraordinary stability and retains the structural integrity, membrane fluidity, membrane protein mobility, and topology of living cells. In assessing the utility of GELL layers as a tissue engineering feeder substrate for stem cell maintenance, GELL feeder prepared from primary mouse embryonic fibroblasts not only preserves the stemness of murine stem cells but also exhibits advantages over live feeder cells owing to the GELL's inanimate, non-metabolizing nature. The preparation of a xeno-free feeder substrate devoid of non-human components is further shown with HeLa cells, and the resulting  HeLa GELL feeder effectively sustains the growth and stemness of both murine and human induced pluripotent stem cells. The study highlights a novel bio-functionalization strategy that introduces new opportunities for tissue engineering and other biomedical applications.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Humanos , Animais , Camundongos , Fibroblastos , Células HeLa , Células Alimentadoras/metabolismo , Diferenciação Celular
4.
Nat Commun ; 10(1): 1057, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30837473

RESUMO

Cell membranes are an intricate yet fragile interface that requires substrate support for stabilization. Upon cell death, disassembly of the cytoskeletal network deprives plasma membranes of mechanical support and leads to membrane rupture and disintegration. By assembling a network of synthetic hydrogel polymers inside the intracellular compartment using photo-activated crosslinking chemistry, we show that the fluid cell membrane can be preserved, resulting in intracellularly gelated cells with robust stability. Upon assessing several types of adherent and suspension cells over a range of hydrogel crosslinking densities, we validate retention of surface properties, membrane lipid fluidity, lipid order, and protein mobility on the gelated cells. Preservation of cell surface functions is further demonstrated with gelated antigen presenting cells, which engage with antigen-specific T lymphocytes and effectively promote cell expansion ex vivo and in vivo. The intracellular hydrogelation technique presents a versatile cell fixation approach adaptable for biomembrane studies and biomedical device construction.

5.
ACS Appl Mater Interfaces ; 9(46): 39953-39961, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29088538

RESUMO

Attachment to cellular surfaces is a major attribute among infectious pathogens for initiating disease pathogenesis. In viral infections, viruses exploit receptor-ligand interactions to latch onto cellular exterior prior to subsequent entry and invasion. In light of the selective binding affinity between viral pathogens and cells, nanoparticles cloaked in cellular membranes are herein employed for virus targeting. Using the influenza virus as a model, erythrocyte membrane cloaked nanoparticles are prepared and modified with magnetic functionalities (RBC-mNP) for virus targeting and isolation. To maximize targeting and isolation efficiency, density gradient centrifugation and nanoparticle tracking analysis were applied to minimize the presence of uncoated particles and membrane vesicles. The resulting nanoparticles possess a distinctive membrane corona, a sialylated surface, and form colloidally stable clusters with influenza viruses. Magnetic functionality is bestowed to the nanoparticles through encapsulation of superparamagnetic iron-oxide particles, which enable influenza virus enrichment via magnetic extraction. Viral samples enriched by the RBC-mNPs result in significantly enhanced virus detection by multiple virus quantification methods, including qRT-PCR, immunnochromatographic strip test, and cell-based titering assays. The demonstration of pathogen targeting and isolation by RBC-mNPs highlights a biologically inspired approach toward improved treatment and diagnosis against infectious disease threats. The work also sheds light on the efficient membrane cloaking mechanism that bestows nanoparticles with cell mimicking functionalities.


Assuntos
Nanopartículas de Magnetita , Membrana Eritrocítica , Magnetismo
6.
BMC Cell Biol ; 15: 31, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-25078495

RESUMO

BACKGROUND: In mammalian cells, ASPL is involved in insulin-stimulated redistribution of the glucose transporter GLUT4 and assembly of the Golgi apparatus. Its putative yeast orthologue, Ubx4, is important for proteasome localization, endoplasmic reticulum-associated protein degradation (ERAD), and UV-induced degradation of RNA polymerase. RESULTS: Here, we show that ASPL is a cofactor of the hexameric ATPase complex, known as p97 or VCP in mammals and Cdc48 in yeast. In addition, ASPL interacts in vitro with NSF, another hexameric ATPase complex. ASPL localizes to the ER membrane. The central area in ASPL, containing both a SHP box and a UBX domain, is required for binding to the p97 N-domain. Knock-down of ASPL does not impair degradation of misfolded secretory proteins via the ERAD pathway. Deletion of UBX4 in yeast causes cycloheximide sensitivity, while ubx4 cdc48-3 double mutations cause proteasome mislocalization. ASPL alleviates these defects, but not the impaired ERAD. CONCLUSIONS: In conclusion, ASPL and Ubx4 are homologous proteins with only partially overlapping functions. Both interact with p97/Cdc48, but while Ubx4 is important for ERAD, ASPL appears not to share this function.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Transporte/metabolismo , Degradação Associada com o Retículo Endoplasmático , Proteínas Nucleares/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfatases/análise , Proteínas de Transporte/análise , Proteínas de Transporte/genética , Deleção de Genes , Técnicas de Inativação de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Mutação , Proteínas Nucleares/análise , Proteínas de Fusão Oncogênica/análise , Proteínas de Fusão Oncogênica/genética , Complexo de Endopeptidases do Proteassoma/análise , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/análise , Proteínas de Saccharomyces cerevisiae/genética
7.
Spine (Phila Pa 1976) ; 39(15): E878-84, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24827511

RESUMO

STUDY DESIGN: The biomechanical effects of Dynesys and Cosmic fixators on transition and adjacent segments were evaluated using the finite-element method. OBJECTIVE: This study investigated the load-transferring mechanisms of 2 dynamic fixators and the fixator-induced effects on the junctional problem of the adjacent segments. SUMMARY OF BACKGROUND DATA: The mobility and flexibility of Dynesys screw-spacer and Cosmic screw-hinge joints preserve motion and share loads for the transition segment. However, the differences in tissue responses and fixator mechanisms among these 2 fixators have not been investigated extensively. METHODS: A lumbosacral model from L1 to S1 levels was developed and subjected to muscular contraction, ligamentous interconnection, compressive force, and trunk moment. A static fixator was instrumented at the moderately degenerative L4-L5 segment to serve as a comparison baseline. Subsequently, the 2 fixators were instrumented at the mildly degenerative L3-L4 segment. The tissue responses of the adjacent segments and the load transmission at the screw-spacer and bone-screw interfaces were compared. RESULTS: Both systems show the ability to protect the transition segment but deteriorate the adjacent segments. The screw-hinge joint and the stiffer rod of the Cosmic system significantly constrained the motion pattern of the transition segment. Comparatively, the Dynesys screw-spacer interfaces make contact with and depart from each other during motion; thus providing higher mobility to the transition segment. However, the highly stressed distribution at the Cosmic bone-screw causes the screw and hinge prone to pullout and fatigue failures. CONCLUSION: Cosmic fixation can better protect the disc and facet joint of the transition segment than can the Dynesys. However, the screw-hinge joint strictly constrains intersegmental motion and deteriorates the junctional problem. The Cosmic system can be chosen to treat more severely degenerative transition segments. With higher flexibility, the Dynesys system is recommended for the transition segment that is healthy or mildly degenerative. LEVEL OF EVIDENCE: N/A.


Assuntos
Parafusos Ósseos , Fixadores Internos , Degeneração do Disco Intervertebral/fisiopatologia , Vértebras Lombares/fisiopatologia , Procedimentos Ortopédicos/instrumentação , Fenômenos Biomecânicos , Cadáver , Simulação por Computador , Análise de Elementos Finitos , Humanos , Degeneração do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Região Lombossacral/fisiopatologia , Região Lombossacral/cirurgia , Modelos Anatômicos , Procedimentos Ortopédicos/métodos , Amplitude de Movimento Articular , Estresse Mecânico
8.
J Biol Chem ; 288(52): 37180-91, 2013 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-24225956

RESUMO

The cell cycle transition is driven by abrupt degradation of key regulators. While ubiquitylation of these proteins has been extensively studied, the requirement for the proteolytic step is less understood. By analyzing the cell cycle function of Cdc48 in the budding yeast Saccharomyces cerevisiae, we found that double mutations in Cdc48 and its adaptor Ubx4 cause mitotic arrest with sustained Clb2 and Cdc20 proteins that are normally degraded in anaphase. The phenotype is neither caused by spindle checkpoint activation nor a defect in the assembly or the activity of the ubiquitylation machinery and the proteasome. Interestingly, the 26S proteasome is mislocalized into foci, which are colocalized with nuclear envelope anchor Sts1 in cdc48-3 ubx4 cells. Moreover, genetic analysis reveals that ubx4 deletion mutant dies in the absence of Rpn4, a transcriptional activator for proteasome subunits, and the proteasome chaperone Ump1, indicating that an optimal level of the proteasome is required for survival. Overexpression of Rpn4 indeed can rescue cell growth and anaphase proteolysis in cdc48-3 ubx4 cells. Biochemical analysis further shows that Ubx4 interacts with the proteasome. Our data propose that Cdc48-Ubx4 acts on the proteasome and uses the chaperone activity to promote its nuclear distribution, thereby optimizing the proteasome level for efficient degradation of mitotic regulators.


Assuntos
Adenosina Trifosfatases/metabolismo , Anáfase/fisiologia , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Chaperonas Moleculares/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Adenosina Trifosfatases/genética , Proteínas de Transporte/genética , Proteínas de Ciclo Celular/genética , Núcleo Celular/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Deleção de Genes , Peptídeos e Proteínas de Sinalização Intracelular , Chaperonas Moleculares/genética , Complexo de Endopeptidases do Proteassoma/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Fuso Acromático/genética , Fuso Acromático/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína com Valosina
9.
Spine (Phila Pa 1976) ; 38(13): E775-82, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23486410

RESUMO

STUDY DESIGN: The pretension of the Dynesys cord was varied to evaluate its effects on both tissue responses and screw-spacer behaviors by the finite-element method. OBJECTIVE: This study aimed to provide detailed information about the motion-preserving and load-shielding mechanisms of the Dynesys screw-spacer joint. SUMMARY OF BACKGROUND DATA: Intuitively, higher cord pretension aims to ensure the occurrence of screw-spacer contact, thus making the spacer the transmitter of the vertebral loads. However, detailed investigations of the cord-pretension effects have not yet been carried out. METHODS.: Using a validated lumbosacral model, the moderately degenerative L4-L5 segment was instrumented by a static fixator and the Dynesys fixator was further used to bridge a mildly degenerative L3-L4 segment. The pre-tended cord was modeled as an elastic spring with 0- and 300-N pretensions. The disc range-of-motion, disc stress, facet force, bone-screw stress, and screw-spacer force were chosen as comparison indices. RESULTS.: At the transition and adjacent segments, the range-of-motion differences between the 2 pretensions were 7.7% and 2.0% on average, respectively. The mechanical differences at the transition and adjacent segments were 9.0% and 5.2% (disc stress) and 9.4% and 9.1% (facet force), respectively. The results indicated that the cord pretension has a minor effect on the adjacent segments in comparison with the transition segment. However, the stress at the screw hub and force of the screw-spacer contact of the 300-N pretension were increased by 33.7% and 316.5% on average than without pretension, respectively. CONCLUSION: The moment arm from the screw-cord center to the fulcrum is significantly less than that of vertebral loads. This leads to the minor effect of increasing the cord pretension on the responses of the adjacent segments. However, the cord pretension can significantly affect both screw-spacer force and bone-screw stress. LEVEL OF EVIDENCE: 4.


Assuntos
Parafusos Ósseos , Vértebras Lombares/cirurgia , Procedimentos Ortopédicos/instrumentação , Próteses e Implantes , Fenômenos Biomecânicos , Elasticidade , Humanos , Fixadores Internos , Disco Intervertebral/fisiopatologia , Vértebras Lombares/patologia , Vértebras Lombares/fisiopatologia , Região Lombossacral , Modelos Anatômicos , Procedimentos Ortopédicos/métodos , Amplitude de Movimento Articular , Estresse Mecânico , Articulação Zigapofisária/fisiopatologia
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