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2.
World J Otorhinolaryngol Head Neck Surg ; 10(3): 173-179, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39233859

RESUMO

Objective: To identify factors that influence the severity of tinnitus via a hierarchical multiple linear regression model. Methods: The study was a retrospective cross-sectional analysis. The study included 331 patients experiencing tinnitus as their primary concern, who visited Shanghai Changzheng Hospital of the Navy Medical University between 2019 and 2021. Data on general health status and disease characteristics were collected from all patients. With their consent, participants underwent audiological evaluatons and completed questionnaires to analyze the characteristics of their tinnitus and the factors influencing its severity. Results: The correlation analysis showed a positive relationship between tinnitus frequency, tinnitus loudness, SAS scores, and PSQI scores with THI scores (P < 0.05) among nine examined variables (gender, handedness, employment status, age, BMI, tinnitus frequency, tinnitus loudness, SAS scores, and PSQI scores). The variables that were extracted from the multiple regression were; for the constant; ß = -51.797, t = -4.484, P < 0.001, variable is significant; for the tinnitus loudness; ß = 0.161, t = 2.604, P < 0.05, variable is significant; for the tinnitus frequency; ß = 0.000, t = 1.269, P = 0.206, variable is not significant; for the SAS scores; ß = 1.310, t = 7.685, P < 0.001, variable is significant; for the PSQI scores; ß = 1.680, t = 5.433, P < 0.001, variable is significant. Therefore, the most accurate model for predicting severity in tinnitus patients is a linear combination of the constant, tinnitus loudness, SAS scores, and PSQI scores, Y(Tinnitus severity) = ß 0 + ß 1 (Tinnitus loudness) + ß 2 (SAS scores) + ß 3 (PSQI scores). ß 0, ß 1, ß 2, and ß 3 are -51.797, 0.161, 1.310 and 1.680, respectively. Conclusion: Tinnitus severity is positively associated with loudness, anxiety levels, and sleep quality. To effectively manage tinnitus in patients, it is essential to promptly identify and address these accompanying factors and related symptoms.

3.
Sci Rep ; 14(1): 20887, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39244598

RESUMO

A quantity of recoverable barite exists in high-density waste drilling fluid. Based on the inefficiencies and complexities of existing recycling methods, a novel pre-treatment approach which includes clean-breaking, high-speed washing, ultrasonic dispersion, and microwave heating and a new depressant (Gellan Gum) was proposed. The floatability, separation efficiency and mechanism were discussed by SEM, adsorption capacity, zeta potential measurements and contact angle tests. The results of reverse flotation experiments results indicated that secondary water washing proves highly effective in enriching a significant quantity of barite solid phase. Subsequent microwave-ultrasonic and flotation can obtain barite of high quality with recovery and density reaching 81.5% and 4.238 g/cm3, respectively. It can be utilized directly in the preparation of drilling fluid. Mechanism studies shown that the per-treatments substantially enhances the barite grade while effectively eliminating low-density solid phases adhering to the barite surface, thus exposing additional contact points between the constituents so as to improve flotation separation. This new recovery scheme has environmental advantages and great reference value for the separation of barite within high-density waste drilling fluids.

4.
JPRAS Open ; 41: 244-251, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39099676

RESUMO

Background: Vascularized composite allotransplantation (VCA) has become a viable option for restoration of devastating injuries that are not amenable to conventional reconstructive techniques. However, the relative scarcity of procedures performed worldwide, as well as the potential for iatrogenic injury with biopsies, makes studying the immunopathogenesis of acute rejection challenging. Translational VCA research focuses on developing strategies to overcome these barriers with the use of animal models can be technically challenging and difficult to replicate without highly trained microsurgeons. Methods: We describe a modified model of a femur-based composite tissue allograft using an adapted vascular cuff anastomotic technique with a tunneled skin flap in a rodent model. Results: The use of a heterotopic osteomyocutaneous flap with a subcutaneously tunneled-skin paddle to the posterolateral aspect of the recipient rodent allows for ease of flap monitoring and reduces the risk of self-mutilation. A total of six transplantations were conducted with no signs of self-mutilation. Operative time decreased as our surgical technique improved, and long-term graft tolerance was possible under our immunosuppressive regimen. Additionally, we demonstrate cases of successful transplantation in both an allogeneic and syngeneic rodent model. Conclusion: Animal models, although technically challenging, are a reliable and reproducible modality that has been used to investigate various aspects of VCA immunology. We describe the success of an osteomyocutaneous flap with a modified vascular cuff anastomosis that can be used by investigators with less experience in microsurgical techniques to further our understanding of VCA physiology. Furthermore, tunneling of the skin paddle reduces the risk of self-mutilation and other external factors affecting the graft.

5.
Nature ; 632(8026): 782-787, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39143208

RESUMO

Hot-carrier transistors are a class of devices that leverage the excess kinetic energy of carriers. Unlike regular transistors, which rely on steady-state carrier transport, hot-carrier transistors modulate carriers to high-energy states, resulting in enhanced device speed and functionality. These characteristics are essential for applications that demand rapid switching and high-frequency operations, such as advanced telecommunications and cutting-edge computing technologies1-5. However, the traditional mechanisms of hot-carrier generation are either carrier injection6-11 or acceleration12,13, which limit device performance in terms of power consumption and negative differential resistance14-17. Mixed-dimensional devices, which combine bulk and low-dimensional materials, can offer different mechanisms for hot-carrier generation by leveraging the diverse potential barriers formed by energy-band combinations18-21. Here we report a hot-emitter transistor based on double mixed-dimensional graphene/germanium Schottky junctions that uses stimulated emission of heated carriers to achieve a subthreshold swing lower than 1 millivolt per decade beyond the Boltzmann limit and a negative differential resistance with a peak-to-valley current ratio greater than 100 at room temperature. Multi-valued logic with a high inverter gain and reconfigurable logic states are further demonstrated. This work reports a multifunctional hot-emitter transistor with significant potential for low-power and negative-differential-resistance applications, marking a promising advancement for the post-Moore era.

6.
Proc Natl Acad Sci U S A ; 121(34): e2320257121, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39150784

RESUMO

Lysosomal degradation pathways coordinate the clearance of superfluous and damaged cellular components. Compromised lysosomal degradation is a hallmark of many degenerative diseases, including lysosomal storage diseases (LSDs), which are caused by loss-of-function mutations within both alleles of a lysosomal hydrolase, leading to lysosomal substrate accumulation. Gaucher's disease, characterized by <15% of normal glucocerebrosidase function, is the most common LSD and is a prominent risk factor for developing Parkinson's disease. Here, we show that either of two structurally distinct small molecules that modulate PIKfyve activity, identified in a high-throughput cellular lipid droplet clearance screen, can improve glucocerebrosidase function in Gaucher patient-derived fibroblasts through an MiT/TFE transcription factor that promotes lysosomal gene translation. An integrated stress response (ISR) antagonist used in combination with a PIKfyve modulator further improves cellular glucocerebrosidase activity, likely because ISR signaling appears to also be slightly activated by treatment by either small molecule at the higher doses employed. This strategy of combining a PIKfyve modulator with an ISR inhibitor improves mutant lysosomal hydrolase function in cellular models of additional LSD.


Assuntos
Fibroblastos , Glucosilceramidase , Doenças por Armazenamento dos Lisossomos , Lisossomos , Fosfatidilinositol 3-Quinases , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Lisossomos/metabolismo , Lisossomos/efeitos dos fármacos , Glucosilceramidase/metabolismo , Glucosilceramidase/genética , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Doenças por Armazenamento dos Lisossomos/tratamento farmacológico , Doenças por Armazenamento dos Lisossomos/genética , Doenças por Armazenamento dos Lisossomos/metabolismo , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Doença de Gaucher/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia
8.
Front Psychiatry ; 15: 1423200, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39161547

RESUMO

Objective: Maintenance hemodialysis (MHD) patients suffer from enormous physical, mental stress and poor quality of life, so an increasing number of patients are in a long-term state of depression. A prominent feature of MHD patients is chronic persistent inflammation, which is also an important mechanism for the onset of depression. Therefore, finding economically convenient inflammatory markers to predict and diagnose the onset of depression in MHD patients is of great value. As a novel inflammatory marker, systemic immune inflammation index (SII) can more comprehensively reflect the inflammation and immunity level of patients. This study aims to explore the relationship between SII and depressive symptoms in MHD patients. Methods: A cross-sectional study was conducted on 206 MHD patients from three dialysis centers. Based on the Hospital Anxiety and Depression Scale (HADS) scores, patients were divided into non-depression and depression groups. Inter group comparison and multivariate logistic regression analysis were performed to determine whether SII is an independent risk factor for depression in MHD patients. Receiver operating characteristic (ROC) curve was used to evaluate the predictive value of SII on depression symptoms in MHD patients. Results: According to the HADS scale score, 38.83% of the included patients were in a state of depression. After adjusting for all confounding factors, MHD patients with SII>963.93 had a 4.709 times higher risk of depression than those with SII ≤ 478.32 (OR=4.709, 95% CI 1.821-12.178, P<0.01). ROC analysis showed that SII>685.11 was the best cutoff value for MHD depression patients, and the area under the curve (AUC) was 0.681. Conclusions: High SII is an independent risk factor for depressed MHD patients and an ideal inflammatory marker for predicting and identifying depression in MHD patients as assessed by the HADS scale.

9.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3627-3635, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39041135

RESUMO

This study investigated the effects of ergosterol peroxide(EP) on the proliferation and apoptosis of MCF-7 breast cancer cells, explored its possible mechanisms of action, and verified the effects and mechanisms by in vitro experiments. Network pharmaco-logy was used to screen the target proteins of EP and construct target networks and protein-protein interaction(PPI) networks to predict the potential target proteins and related pathways involved in EP anti-breast cancer effects. The MTT assay was performed to measure the inhibitory effect of EP on MCF-7 cell proliferation, and the colony formation assay was used to assess the cell cloning ability. Flow cytometry and laser confocal microscopy were employed to evaluate cell apoptosis, mitochondrial membrane potential and reactive oxygen species(ROS) levels. Western blot analysis was conducted to examine the expression levels of B-cell lymphoma 2(Bcl-2), Bcl-2-associated X protein(Bax), cytochrome C(Cyt C), caspase-7, cleaved caspase-7, phosphatidylinositol 3-kinase(PI3K), and se-rine/threonine kinase B(AKT) in MCF-7 cells treated with EP. The results of network pharmacology prediction yielded 173 common targets between EP and breast cancer; the results of Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analysis showed that EP treatment for breast cancer mainly affected the signaling pathways such as cancer pathway, PI3K-AKT signaling pathway, cellular senescence signaling pathway, and viral carcinogenesis pathway; and the MTT assay results showed that the viability of MCF-7 cells in the EP group was significantly lower than that in the control group, exhibiting a time-and concentration-dependent trend, and EP can inhibit colony formation of MCF-7 breast cancer cells. Treatment with 10, 20, and 40 µmol·L~(-1) EP for 24 h resulted in a significant increase in the total apoptosis rate of MCF-7 cells, a significant decrease in mitochondrial membrane potential, and a significant increase in ROS levels. In addition, treatment with EP led to an upregulation of Cyt C, Bax, and cleaved caspase-7 protein expression, and a downregulation of p-PI3K, p-AKT, and Bcl-2 protein expression in MCF-7 cells. Studies have shown that EP inhibits MCF-7 breast cancer cell proliferation and reduces colony formation by a mechanism that may be related to the PI3K-AKT pathway mediating the mitochondrial apoptotic pathway.


Assuntos
Apoptose , Neoplasias da Mama , Proliferação de Células , Ergosterol , Farmacologia em Rede , Humanos , Células MCF-7 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ergosterol/análogos & derivados , Ergosterol/farmacologia , Feminino , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Citocromos c/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética
10.
Int J Ophthalmol ; 17(7): 1344-1362, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39026906

RESUMO

Age-related macular degeneration (AMD) is a complicated disease that causes irreversible visual impairment. Increasing evidences pointed retinal pigment epithelia (RPE) cells as the decisive cell involved in the progress of AMD, and the function of anti-oxidant capacity of PRE plays a fundamental physiological role. Nuclear factor erythroid 2 related factor 2 (Nrf2) is a significant transcription factor in the cellular anti-oxidant system as it regulates the expression of multiple anti-oxidative genes. Its functions of protecting RPE cells against oxidative stress (OS) and ensuing physiological changes, including inflammation, mitochondrial damage and autophagy dysregulation, have already been elucidated. Understanding the roles of upstream regulators of Nrf2 could provide further insight to the OS-mediated AMD pathogenesis. For the first time, this review summarized the reported upstream regulators of Nrf2 in AMD pathogenesis, including proteins and miRNAs, and their underlying molecular mechanisms, which may help to find potential targets via regulating the Nrf2 pathway in the future research and further discuss the existing Nrf2 regulators proved to be beneficial in preventing AMD.

11.
Mol Neurobiol ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985257

RESUMO

Perioperative neurocognitive dysfunction is a significant concern for population health, impacting postoperative recovery and increasing the financial burden on patients. With an increasing number of surgical procedures being performed, the prevention and management of perioperative neurocognitive dysfunction have garnered significant attention. While factors such as age, lifestyle, genetics, and education are known to influence the development of cognitive dysfunction, recent research has highlighted the role of the gut microbiota in neurological health. An increased abundance of pro-inflammatory gut microbiota can trigger and worsen neuroinflammation, neuronal cell damage, and impaired cellular autophagy. Moreover, the inflammation-promoting gut microbiota can disrupt immune function, impair neuroautophagy, and affect the production and circulation of extracellular vesicles and neurotransmitters. These factors collectively play a role in the onset and advancement of cognitive impairment. This narrative review delves into the molecular mechanisms through which gut microbiota and their derivatives contribute to cognitive impairment, focusing on the impact of anesthesia surgery, changes in gut microbial populations, and perioperative cognitive impairment associations. The study suggests that alterations in the abundance of various bacterial species and their metabolites pre- and post-surgery may be linked to postoperative cognitive impairment. Furthermore, the potential of probiotics or prebiotics in addressing cognitive impairment is discussed, offering a promising avenue for investigating the treatment of perioperative neurocognitive disorders.

12.
Aging Clin Exp Res ; 36(1): 140, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965150

RESUMO

BACKGROUND: Sarcopenia has been reported to play an important role in frailty syndrome. The serum creatinine/serum cystatin C ratio (Scr/Cys C ratio) has recently been recognized as a valuable indicator for assessing sarcopenia. However, few studies have examined the association between serum creatinine/serum cystatin C ratio and frailty. The objective of this study is to investigate the relationship between the serum creatinine/serum cystatin C ratio and frailty among older adults residing in the community. METHODS AND MATERIALS: A Total of 1926 community-dwelling older adults aged ≥ 60 years in the 2011 waves of the China Health and Retirement Longitudinal Study (CHARLS) were included. The participants' frailty status was determined using a 39 item frailty index (FI), which classified individuals as "robust" (FI ≤ 0.1), "pre-frailty" (0.1 < FI < 0.25), or "frailty" (FI ≥ 0.25). The Scr/Cys C ratio was determined by dividing the serum creatinine level (mg/dL) by the cystatin C level (mg/L). The one-way analysis of variance(ANOVA) and Chi-squared test (χ2)were applied to compare the differences between the 3 groups. Both linear regression and logistic regression models were used to further investigate the relationship between Scr/Cys C ratio and frailty. RESULTS: After adjusting for potential confounding factors, the study revealed that participants in the Q1 quartile of Scr/Cys C ratio had increased odds of frailty (Q1vs.Q4: OR = 1.880, 95% CI 1.126-3.139, p = 0.016) compared with those in the Q4 quartile group. In fully adjusted logistic regression models, male participants in the Q2 quartile of Scr/Cys C ratio were significantly correlated with higher odds of pre-frailty (Q2 vs.Q4: OR = 1.693, 95%CI 1.040-2.758, p = 0.034). However, this correlation was not observed in females (OR = 0.984, 95% CI 0.589-1.642, p = 0.950,). Additionally, the study observed an increase in both the frailty index and the incidence of frailty as age increased in both males and females. CONCLUSION: Among community-dwelling older adults, lower Serum creatinine to cystatin C ratio were found to be associated with increased odds of frailty prevalence in males.


Assuntos
Creatinina , Cistatina C , Fragilidade , Vida Independente , Humanos , Cistatina C/sangue , Masculino , Idoso , Creatinina/sangue , Feminino , Fragilidade/sangue , Fragilidade/epidemiologia , Idoso de 80 Anos ou mais , Incidência , Pessoa de Meia-Idade , Idoso Fragilizado/estatística & dados numéricos , China/epidemiologia , Estudos Longitudinais , Sarcopenia/sangue , Sarcopenia/epidemiologia , Fatores Sexuais , Biomarcadores/sangue , Avaliação Geriátrica/métodos
13.
Mol Psychiatry ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003414

RESUMO

Neuroligin-3 (Nlgn3) is an autism-associated cell-adhesion molecule that interacts with neurexins and is robustly expressed in both neurons and astrocytes. Neuronal Nlgn3 is an essential regulator of synaptic transmission but the function of astrocytic Nlgn3 is largely unknown. Given the high penetrance of Nlgn3 mutations in autism and the emerging role of astrocytes in neuropsychiatric disorders, we here asked whether astrocytic Nlgn3 might shape neural circuit properties in the cerebellum similar to neuronal Nlgn3. Imaging of tagged Nlgn3 protein produced by CRISPR/Cas9-mediated genome editing showed that Nlgn3 is enriched in the cell body but not the fine processes of cerebellar astrocytes (Bergmann glia). Astrocyte-specific knockout of Nlgn3 did not detectably alter the number of synapses, synaptic transmission, or astrocyte morphology in mouse cerebellum. However, spatial transcriptomic analyses revealed a significant shift in gene expression among multiple cerebellar cell types after the deletion of astrocytic Nlgn3. Hence, in contrast to neuronal Nlgn3, astrocytic Nlgn3 in the cerebellum is not involved in shaping synapses but may modulate gene expression in specific brain areas.

14.
Diagnostics (Basel) ; 14(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39061693

RESUMO

The study aimed to investigate the extended effects and interrelations of corneal biomechanics, corneal optical density (COD), corneal thickness (CT), and intraocular pressure (IOP) following cataract surgery. Sixteen eyes were analyzed prospectively. The Corneal Visualization Scheimpflug Technology (Corvis ST) device assessed corneal biomechanics, while the Pentacam AxL® (Pentacam) measured COD and CT. Postoperative data were collected around six months after surgery, with a subgroup analysis of data at nine months. The Pearson correlation was used to examine the relationship between surgical-induced changes in corneal biomechanics and COD. At six months, significant postoperative differences were observed in various biomechanical indices, including uncorrected IOP (IOPuct) and biomechanics-corrected IOP (bIOP). However, many indices lost statistical significance by the nine-month mark, suggesting the reversibility of postoperative corneal changes. Postoperative COD increased at the anterior layer of the 2-6 mm annulus and incision site. The changes in COD correlated with certain biomechanical indices, including maximal (Max) deformative amplitude (DA) and stiffness parameter (SP). In conclusion, despite significant immediate postoperative changes, corneal biomechanics, COD, and IOP experienced a gradual recovery process following cataract surgery. Clinicians should maintain vigilance for any unusual changes during the short-term observation period to detect abnormalities early.

15.
J Subst Use Addict Treat ; 165: 209459, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39067768

RESUMO

BACKGROUND: Recovery community centers (RCCs) are a relatively new resource in the recovery support landscape aimed at building their members' recovery capital. In recent years, interest in the value of RCCs has grown, however, no studies have used within-person methods to consider how RCCs may impact the day-to-day lives of their attendees. Using within-person data drawn from members of RCCs, this study examined how visiting RCCs was associated with several same-day indicators of recovery wellbeing and risk: daily sense of meaningfulness, recovery identity, negative affect, and positive affect. METHODS: Participants were 94 visitors of six RCCs in western Pennsylvania. Daily diary methods collected 10 nightly reports of daily RCC attendance and end-of-day meaningfulness, recovery identity, negative affect, and positive affect. Multilevel modeling accounted for nesting in the intensive longitudinal data. In independent models, the study regressed meaningfulness, recovery identity, negative affect, and positive affect onto day- and person-level RCC attendance. RESULTS: Within-person associations between RCC attendance and meaningfulness (b = 6.96, SE = 1.66, p < .001), recovery identity (b = 4.75, SE = 1.08, p < .001), and PA (b = 3.82, SE = 1.45, p < .01) were significant, although NA was not (b = -2.41, SE = 1.34, n.s.). All day- by person-level RCC attendance interactions (in preliminary models) and between-person associations were non-significant across recovery outcomes. CONCLUSIONS: The results indicated that on days participants visited RCCs, they reported significantly higher levels of meaningfulness, recovery identity, and positive affect, although negative affect levels did not significantly differ. Also, those who attended RCCs more frequently did not generally report different levels of recovery wellbeing and risk. Taken together, results suggest visiting RCCs works on a daily basis to support interpersonal processes related to positive recovery outcomes. That RCC visits do not appear to reduce negative affect suggests that additional programs may be needed to address negative affect. The within-person design provided insight into the dynamic processes that contribute to the intrapersonal states that support recovery and a practical approach to examining whether and how RCCs might support recovery. By using individuals as their own controls, the study design provided strong counterfactual inference.


Assuntos
Afeto , Bem-Estar Psicológico , Transtornos Relacionados ao Uso de Substâncias , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pennsylvania , Transtornos Relacionados ao Uso de Substâncias/reabilitação
16.
aBIOTECH ; 5(2): 214-218, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38974869

RESUMO

Efficient and precise genomic deletion shows promise for investigating the function of proteins in plant research and enhancing agricultural traits. In this study, we tested the PRIME-Del (PDel) strategy using a pair of prime editing guide RNAs (pegRNAs) that targeted opposite DNA strands and achieved an average deletion efficiency of 55.8% for 60 bp fragment deletions at six endogenous targets. Moreover, as high as 84.2% precise deletion efficiency was obtained for a 2000 bp deletion at the OsGS1 site in transgenic rice plants. To add the bases that were unintentionally deleted between the two nicking sequences, we used the PDel/Syn strategy, which introduced multiple synonymous base mutations in the region that had to be patched in the RT template. The PDel/Syn strategy achieved an average of 58.1% deletion efficiency at six endogenous targets, which was higher than the PDel strategy. The strategies presented in this study contribute to achieving more accurate and flexible deletions in transgenic rice plants. Supplementary Information: The online version contains supplementary material available at 10.1007/s42994-024-00153-9.

17.
ACS Omega ; 9(22): 24095-24104, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38854553

RESUMO

Herein, we propose a Carbopol hydrogel-based oxygen nanodelivery "nanohyperbaric" system as a wound dressing material for an enhanced wound healing process. Oxygen nanobubbles (ONBs) were used to supply oxygen, and collagenase was added in the gel as a drug model. Both oxygen and collagenase would benefit the wound healing process, and the Carbopol hydrogel serves as the matrix to load ONBs and collagenase in the wound dressing. The obtained ONB-embedded Carbopol hydrogel with collagenase (ONB-CC) could provide 12.08 ± 0.75 µg of oxygen from 1 mL of ONB-CC and exhibited a notable capacity to prolong the oxygen holding for up to 3 weeks and maintained the enzymatic activity of collagenase at more than 0.05 U per 0.1 mL of ONB-CC for up to 17 days. With HDFa cells, the ONB-CC did not show a notable effect on the cell viability. In a scratch assay, the oxygen from ONBs or collagenase aided cell migration; further, the ONB-CC induced the most obvious scratch closure, indicating an improvement in wound healing as a cocktail in the ONB-CC. The mRNA expression further demonstrated the effectiveness of the ONB-CC. Studies in rats with punched wounds treated with the ONB-CC dressing showed improved wound closure. Histopathological images showed that the ONB-CC dressing enhanced re-epithelization and formation of new blood vessels and hair follicles. The proposed ONB-CC has excellent potential as an ideal wound dressing material to accelerate wound healing by integration of multiple functions.

18.
Acta Pharmacol Sin ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914677

RESUMO

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have obvious advantages over MSC therapy. But the strong procoagulant properties of MSC-EVs pose a potential risk of thromboembolism, an issue that remains insufficiently explored. In this study, we systematically investigated the procoagulant activity of large EVs derived from human umbilical cord MSCs (UC-EVs) both in vitro and in vivo. UC-EVs were isolated from cell culture supernatants. Mice were injected with UC-EVs (0.125, 0.25, 0.5, 1, 2, 4 µg/g body weight) in 100 µL PBS via the tail vein. Behavior and mortality were monitored for 30 min after injection. We showed that these UC-EVs activated coagulation in a dose- and tissue factor-dependent manner. UC-EVs-induced coagulation in vitro could be inhibited by addition of tissue factor pathway inhibitor. Notably, intravenous administration of high doses of the UC-EVs (1 µg/g body weight or higher) led to rapid mortality due to multiple thrombus formations in lung tissue, platelets, and fibrinogen depletion, and prolonged prothrombin and activated partial thromboplastin times. Importantly, we demonstrated that pulmonary thromboembolism induced by the UC-EVs could be prevented by either reducing the infusion rate or by pre-injection of heparin, a known anticoagulant. In conclusion, this study elucidates the procoagulant characteristics and mechanisms of large UC-EVs, details the associated coagulation risk during intravenous delivery, sets a safe upper limit for intravenous dose, and offers effective strategies to prevent such mortal risks when high doses of large UC-EVs are needed for optimal therapeutic effects, with implications for the development and application of large UC-EV-based as well as other MSC-EV-based therapies.

19.
Int J Biol Macromol ; 273(Pt 1): 132993, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38862049

RESUMO

Low ionic conductivity and poor interface stability of poly(ethylene oxide) (PEO) restrict the practical application as polymeric electrolyte films to prepare solid-state lithium (Li) metal batteries. In this work, biomass-based carboxymethyl chitosan (CMCS) is designed and developed as organic fillers into PEO matrix to form composite electrolytes (PEO@CMCS). Carboxymethyl groups of CMCS fillers can promote the decomposition of Lithium bis(trifluoromethane sulfonimide) (LiTFSI) to generate more lithium fluoride (LiF) at CMCS/PEO interface, which not only forms ionic conductive network to promote the rapid transfer of Li+ but also effectively enhances the interface stability between polymeric electrolyte and Li metal. The enrichment of carboxyl, hydroxyl, and amidogen functional groups within CMCS fillers can form hydrogen bonds with ethylene oxide (EO) chains to improve the tensile properties of PEO-based electrolyte. In addition, the high hardness of CMCS additives can also strengthen mechanical properties of PEO-based electrolyte to resist penetration of Li dendrites. LiLi symmetric batteries can achieve stable cycle for 2500 h and lithium iron phosphate full batteries can maintain 135.5 mAh g-1 after 400 cycles. This work provides a strategy for the enhancement of ion conductivity and interface stability of PEO-based electrolyte, as well as realizes the resource utilization of biomass-based CMCS.


Assuntos
Quitosana , Condutividade Elétrica , Fontes de Energia Elétrica , Eletrólitos , Lítio , Polietilenoglicóis , Quitosana/química , Quitosana/análogos & derivados , Polietilenoglicóis/química , Lítio/química , Eletrólitos/química , Íons/química
20.
J Colloid Interface Sci ; 673: 104-112, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38875782

RESUMO

Flexible electrodes based on conversion-type materials have potential applications in low-cost and high-performance flexible sodium-ion batteries (FSIBs), owing to their high theoretical capacity and appropriate sodiation potential. However, they suffer from flexible electrodes with poor mechanical properties and sluggish reaction kinetics. In this study, freestanding CoS2 nanoparticles coupled with graphene oxides and carbon nanotubes (CoS2/GO/CNTs) flexible films with robust and interconnected architectures were successfully synthesized. CoS2/GO/CNTs flexible film displays high electronic conductivity and superior mechanical properties (average tensile strength of 21.27 MPa and average toughness of 393.18 KJ m-3) owing to the defect bridge for electron transfer and the formation of the π-π interactions between CNTs and GO. In addition, the close contact between the CoS2 nanoparticles and carbon networks enabled by the Co-N chemical bond prevents the self-aggregation of the CoS2 nanoparticles. As a result, the CoS2/GO/CNTs flexible film delivered superior rate capability (213.5 mAh g-1 at 6 A g-1, better than most reported flexible anode) and long-term cycling stability. Moreover, the conversion reaction that occurred in the CoS2/GO/CNTs flexible film exhibited pseudocapacitive behavior. This study provides meaningful insights into the development of flexible electrodes with superior mechanical properties and electrochemical performance for energy storage.

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