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1.
Neural Regen Res ; 20(5): 1221-1235, 2025 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-39075892

RESUMO

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional recovery. Therefore, there is an urgent need to develop new methods for the treatment of this condition. Exosomes are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological conditions. They have low immunogenicity, good stability, high delivery efficiency, and the ability to cross the blood-brain barrier. These physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic stroke. The rapid development of nanotechnology has advanced the application of engineered exosomes, which can effectively improve targeting ability, enhance therapeutic efficacy, and minimize the dosages needed. Advances in technology have also driven clinical translational research on exosomes. In this review, we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke, including their anti-inflammation, anti-apoptosis, autophagy-regulation, angiogenesis, neurogenesis, and glial scar formation reduction effects. However, it is worth noting that, despite their significant therapeutic potential, there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified exosomes. Future optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic stroke. Ultimately, our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

2.
Invest Ophthalmol Vis Sci ; 65(10): 19, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39133471

RESUMO

Purpose: High altitude retinopathy (HAR) is a retinal functional disorder caused by inadequate adaptation after exposure to high altitude. However, the cellular and molecular mechanisms underlying retinal dysfunction remain elusive. Retinal ganglion cell (RGC) injury is the most important pathological basis for most retinal and optic nerve diseases. Studies focusing on RGC injury after high-altitude exposure (HAE) are scanty. Therefore, the present study sought to explore both functional and morphological alterations of RGCs after HAE. Methods: A mouse model of acute hypobaric hypoxia was established by mimicking the conditions of a high altitude of 5000 m. After HAE for 2, 4, 6, 10, 24, and 72 hours, the functional and morphological alterations of RGCs were assessed using retinal hematoxylin and eosin (H&E) sections, retinal whole mounts, transmission electron microscopy (TEM), and the photopic negative response (PhNR) of the electroretinogram. Results: Compared with the control group, the thickness of the ganglion cell layer and retinal nerve fiber layer increased significantly, RGC loss remained significant, and the amplitudes of a-wave, b-wave, and PhNR were significantly reduced after HAE. In addition, RGCs and their axons exhibited an abnormal ultrastructure after HAE, including nuclear membrane abnormalities, uneven distribution of chromatin in the nucleus, decreased cytoplasmic electron density, widening and vacuolization of the gap between axons, loosening and disorder of myelin sheath structure, widening of the gap between myelin sheath and axon membrane, decreased axoplasmic density, unclear microtubule and nerve fiber structure, and abnormal mitochondrial structure (mostly swollen, with widened membrane gaps and reduced cristae and vacuolization). Conclusions: The study findings confirm that the morphology and function of RGCs are damaged after HAE. These findings lay the foundation for further study of the specific molecular mechanisms of HAR and promote the effective prevention.


Assuntos
Modelos Animais de Doenças , Eletrorretinografia , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Células Ganglionares da Retina , Animais , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/ultraestrutura , Camundongos , Masculino , Doença da Altitude/fisiopatologia , Doença da Altitude/patologia , Doenças Retinianas/fisiopatologia , Doenças Retinianas/etiologia , Doenças Retinianas/patologia , Altitude , Doença Aguda
3.
J Thorac Dis ; 16(7): 4429-4439, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39144308

RESUMO

Background: Limited data are available regarding the current microbiological characteristics of extracorporeal membrane oxygenation (ECMO)-related infections in intensive care units (ICUs) in China. This retrospective study aimed to determine the epidemiology, risk factors and impact on the outcome of ECMO-related infections. Methods: A retrospective observational study from January 2014 to December 2019 was performed, and adult patients receiving ECMO support for more than 48 hours were included in this study. The primary outcome was the incidence rate of ECMO-related infection. Clinical data were recorded, and risk factors associated with an increased risk of ECMO-related infection were analyzed. Results: A total of 174 adult patients who received ECMO and underwent ECMO for 1,670 days were included in this study. Forty-six patients (26.4%) developed ECMO-related infections, corresponding to 27.5 first episodes/1,000 ECMO days. The most common ECMO-related infection observed was ventilator-associated pneumonia (VAP). Infected patients had longer durations of mechanical ventilation {20.2 [interquartile range (IQR), 12.6, 30.7] vs. 9.0 (IQR, 5.8, 14.7) days, P<0.001}, ECMO support [11.6 (IQR, 8.1, 17.3) vs. 7.6 (IQR, 5.6, 9.7) days, P<0.001] and hospital stays (28.2±20.7 vs. 22.0±15.6 days, P<0.001). The factors independently associated with ECMO-related infection were a dynamic decrease in lymphocyte count [adjusted odds ratio (OR) =3.578, 95% confidence interval (CI): 2.175-4.906, P<0.001] and ECMO duration (adjusted OR =1.207, 95% CI: 1.096-1.330, P<0.001). Compared to patients without infection, infected patients had greater hospital mortality (39.1% vs. 78.3%, P<0.001) and 90-day mortality (40.6% vs. 87.0%, P<0.001). ECMO-related infections were associated with worse outcomes (adjusted Kaplan-Meier curve, log rank test P<0.001). Conclusions: Patients supported by ECMO had a high risk of developing ECMO-related infection. The most common ECMO-related infection observed was VAP. A dynamic decrease in lymphocyte counts was significantly associated with an increased risk of ECMO-related infection.

4.
Opt Lett ; 49(16): 4689-4692, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146136

RESUMO

Based on polarization holography, circular polarization beam splitters with separation angles of up to 100° have been fabricated. The left- and right-handed circularly polarized waves can be reconstructed by the two holograms that were designed by the tensor theory of polarization holography, respectively. In the fabrication of circular polarization beam splitters, two holograms were recorded only by the interference method in the same area of the polarization-sensitive material. This method is simple, inexpensive, and easy to adjust the separation angles and element size. The diffraction efficiency and the polarization state of the reconstructed waves were tested under different incident waves, and the experimental results are in good agreement with the theory. This work not only deepens our understanding of polarization holography but also expands the applications of polarization holography.

5.
Surgery ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39147667

RESUMO

BACKGROUND: Rectal neuroendocrine neoplasms are relatively rare. Patients with rectal neuroendocrine neoplasms undergoing radical surgery have a higher rate of lymph node metastases. Robust evidence on the status of lateral pelvic lymph node metastases and the role of lateral pelvic lymph node dissection in those patients is lacking. This case-series study aimed to explore and address these issues. METHODS: This single-center, prospective case series consecutively enrolled patients with biopsy-proven rectal neuroendocrine neoplasms in a tertiary referral hospital between June 2022 and January 2024. All eligible patients underwent laparoscopic total mesorectal excision surgery and bilateral lateral pelvic lymph node dissection under general anesthesia. The clinicopathologic features, surgical outcomes, and postoperative complications were presented. The last follow-up was conducted in March 2024. RESULTS: A total of 11 patients with rectal neuroendocrine neoplasms-3 female and 8 male-were enrolled. The average age was 60.0 years (range, 53.5-65.5 years), and the median tumor size was 2.0 cm (range, 1.6-2.5 cm). Tumors invaded the muscularis propria in 7 patients. There were 3 cases of neuroendocrine tumor G1, 6 cases of neuroendocrine tumor G2, and 2 cases of neuroendocrine carcinoma. Among these patients, 11 (100.0%) had lymph node metastases, and 6 (54.5%) had lateral pelvic lymph node metastases. In addition, in 2 patients, only lateral pelvic lymph node metastases were observed, without involvement of the mesenteric lymph nodes. Five patients had tumors located on the left wall of the rectum, and only left-sided lateral pelvic lymph node metastases were observed. The other patient had both sides of lateral pelvic lymph node metastases due to circumferential growth of the tumor around the rectum. Anal preservation was achieved in all patients. The median operating time was 235.0 minutes (range, 210.5-335.5 minutes), and the median estimated blood loss was 50.0 mL (range, 45.0-75.0 mL). Two patients experienced postoperative dysuria and recovered spontaneously within 2-4 months after surgery. CONCLUSION: On the basis of a prospective case series, we demonstrate, for the first time, the lateral pelvic lymph node metastasis status in patients with rectal neuroendocrine neoplasms requiring radical total mesorectal excision surgery. Simultaneous bilateral lateral pelvic lymph node dissection may be a feasible and beneficial procedure for preventing local recurrence in these patients due to the lack of definitive neoadjuvant or adjuvant therapy options.

6.
Rev Cardiovasc Med ; 25(7): 258, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39139418

RESUMO

Background: It is crucial to accurately predict the disease progression of systemic arterial hypertension in order to determine the most effective therapeutic strategy. To achieve this, we have employed a multimodal data-integration approach to predict the longitudinal progression of new-onset systemic arterial hypertension patients with suspected obstructive sleep apnea (OSA) at the individual level. Methods: We developed and validated a predictive nomogram model that utilizes multimodal data, consisting of clinical features, laboratory tests, and sleep monitoring data. We assessed the probabilities of major adverse cardiac and cerebrovascular events (MACCEs) as scores for participants in longitudinal cohorts who have systemic arterial hypertension and suspected OSA. In this cohort study, MACCEs were considered as a composite of cardiac mortality, acute coronary syndrome and nonfatal stroke. The least absolute shrinkage and selection operator (LASSO) regression and multiple Cox regression analyses were performed to identify independent risk factors for MACCEs among these patients. Results: 448 patients were randomly assigned to the training cohort while 189 were assigned to the verification cohort. Four clinical variables were enrolled in the constructed nomogram: age, diabetes mellitus, triglyceride, and apnea-hypopnea index (AHI). This model accurately predicted 2-year and 3-year MACCEs, achieving an impressive area under the receiver operating characteristic (ROC) curve of 0.885 and 0.784 in the training cohort, respectively. In the verification cohort, the performance of the nomogram model had good discriminatory power, with an area under the ROC curve of 0.847 and 0.729 for 2-year and 3-year MACCEs, respectively. The correlation between predicted and actual observed MACCEs was high, provided by a calibration plot, for training and verification cohorts. Conclusions: Our study yielded risk stratification for systemic arterial hypertension patients with suspected OSA, which can be quantified through the integration of multimodal data, thus highlighting OSA as a spectrum of disease. This prediction nomogram could be instrumental in defining the disease state and long-term clinical outcomes.

7.
Front Plant Sci ; 15: 1413507, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139723

RESUMO

Corn-soybean rotation is a cropping pattern to optimize crop structure and improve resource use efficiency, and nitrogen (N) fertilizer application is an indispensable tool to increase corn yields. However, the effects of N fertilizer application levels on corn yield and soil N storage under corn-soybean rotation have not been systematically studied. The experimental located in the central part of the Songnen Plain, a split-zone experimental design was used with two planting patterns of continuous corn (CC) and corn-soybean rotations (RC) in the main zone and three N application rates of 0, 180, and 360 kg hm-2 of urea in the secondary zone. The research has shown that RC treatments can enhance plant growth and increase corn yield by 4.76% to 79.92% compared to CC treatments. The amount of N fertilizer applied has a negative correlation with yield increase range, and N application above 180 kg hm-2 has a significantly lower effect on corn yield increase. Therefore, a reduction in N fertilizer application may be appropriate. RC increased soil N storage by improving soil N-transforming enzyme activity, improving soil N content and the proportion of soil organic N fractions. Additionally, it can improve plant N use efficiency by 1.4%-5.6%. Soybeans grown in corn-soybean rotations systems have the potential to replace more than 180 kg hm-2 of urea application. Corn-soybean rotation with low N inputs is an efficient and sustainable agricultural strategy.

8.
ACS Med Chem Lett ; 15(8): 1242-1249, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39140067

RESUMO

Osteoporosis, a global bone disease, results in decreased bone density, mass, and microarchitecture deterioration, increasing fracture risk. In previous research, FRATtide, a peptide derived from a glycogen synthase kinase-3 binding protein, effectively hindered osteoclast differentiation to yield therapeutically potent derivatives via single and double stapling. However, FRATtide's structure-activity relationship remains unclear. This study synthesized 25 FRATtide-derived peptides through systematic alanine scanning and evaluated their activities. Substitutions in Pro2, Leu5, Leu9, Val10, Leu11, Ser12, Asn14, Leu15, Ile16, Glu18, Arg22, Ser25, and Arg26 showed reduced activity, while FRT13 and FRT20 with Gly13 and Arg21 substitutions, respectively, displayed enhanced activities. F-actin binding and bone resorption assays on FRT13 and FRT20 showed better inhibition of osteoclast differentiation and bone resorption compared with FRATtide. This study elucidated FRATtide's structure-activity relationship, thereby facilitating future structural optimization for osteoporosis treatment.

9.
Mar Pollut Bull ; 207: 116830, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39142053

RESUMO

Hypoxia and acidification are universal environmental issues in coastal seas, especially in large river dominated shelves, and the East China Sea shelf is a typical case among them. However, the responses of status of hypoxia and acidification in coastal seas to the extremes of river discharges are still to be revealed. This study surveyed the influences of a summer drought on the status of hypoxia and acidification on the inner East China Sea shelf off the Changjiang estuary. In August of 2023 during a summer drought, carbonate system parameters and dissolved oxygen (DO) were surveyed on the East China Sea shelf off the Changjiang estuary. As expected, dissolved inorganic carbon (DIC) removal (up to >40 µmol kg-1) and DO over-saturation (up to >110 %) accompanied by high pH (up to >8.15) in the surface water were observed. However, low DO (32-172 µmol kg-1), low pH (7.63-8.04) and low saturation state index of aragonite (ΩAr) (1.34-3.06) in the bottom water were observed. Relationships of Excess DIC with DO consumption, and pH and ΩAr with Excess DIC indicated that the hypoxia and acidification in the bottom water was due mainly to the remineralization of the marine-sourced organic matter. Nevertheless, both hypoxia and acidification were mitigated, i.e. the hypoxic area was smaller, the minimum DO concentration, pH and saturation state index of aragonite were higher in August of 2023 than under the general summer condition. The lower Changjiang discharge (∼60 % of the long-term monthly average) mitigated eutrophication of the East China Sea shelf and decreased the phytoplankton biomass in the surface water and subsequently the hypoxia and acidification in the bottom water. However, acidification of the bottom water on the East China Sea shelf was still severe even during the summer drought. Regulating the anthropogenic impact on the coastal marginal seas is still urgently needed to mitigate the acidification status.

10.
Biomacromolecules ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145523

RESUMO

Lanthanide-containing luminescent hydrogels have shown potential for sensing and imaging applications. Nonetheless, integrating lanthanide ions or complexes into the polymer matrix often results in the poor stability and mechanical strength of the hydrogels. This work presents an innovative approach to fabricating luminescent hydrogels with three dynamic cross-links: imine bond, boronate ester bond, and metal-ligand coordination. Europium(III) (Eu3+) ions are incorporated into a dual-cross-linked matrix composed of phenylboronic acid-polyethylenimine-modified gelatin (PPG) and alginate dialdehyde (ADA) through a combined treatment involving freeze-drying-swelling (FDS) and freeze-thawing (FT) processes. The FDS process facilitates the formation of additional europium-carboxylate cross-links within the polymeric network to enhance its luminescence and stability, while the FT process strengthens the network physically. The impact of the FDS-FT cycle number on the microstructures and properties of PPG/ADA-Eu3+ hydrogels is thoroughly investigated, and their potential for monitoring bacterial growth and detecting copper(II) ions is also demonstrated.

11.
Int Immunopharmacol ; 140: 112850, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39116488

RESUMO

OBJECTIVE: Collagen-induced arthritis (CIA) model was induced in C57BL/6 wild-type (wt) and C57BL/6 miR-204/-211 double-knockout (dKO) mice to investigate the role of miR-204/-211 in suppressing splenic inflammation in rheumatoid arthritis (RA). METHODS: Differences of miR-204/-211 and structure-specific recognition protein 1 (SSRP1) in the spleen of DBA/1J wt and CIA mice were detected via PCR and immunohistochemistry. CIA was induced in both C57BL/6 wt and C57BL/6 miR-204/-211 dKO mice, and the onset of CIA and disease severity were statistically analyzed. Immunohistochemistry staining of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and SSRP1 in spleen or knee joints was performed and analyzed. In CIA miR-204/-211 dKO mice, AAV-shSSRP1 was intra-articularly injected, with both the AAV-shRNA Ctrl and AAV-shRNA Ctrl CIA groups receiving the same dose of AAV-shRNA. Spleen sections were stained with hematoxylin and eosin (H&E). RESULTS: Compared to wt mouse spleens, aberrant expression of miR-204/-211 and SSRP1 was observed in the spleens of CIA mice. Immunized dKO mice exhibited a higher incidence of CIA onset and a more exacerbated RA disease phenotype, characterized by increased spleen inflammation score and elevated levels of IL-1ß, TNF-α, and SSRP1 expression. AAV-shSSRP1 injection in CIA dKO mice significantly reduced spleen inflammation scores, IL-1ß and TNF-α expression levels, and down-regulated Ki-67 expression compared to CIA dKO mice. CONCLUSION: Knockout of miR-204/-211 exacerbated the onset of CIA in C57BL/6 mice, while miR-204/-211 played a protective role against the progression of splenic inflammatory and proliferative progression in RA by targeting SSRP1.

12.
Research (Wash D C) ; 7: 0424, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39130493

RESUMO

Research on the flexible hybrid epidermal electronic system (FHEES) has attracted considerable attention due to its potential applications in human-machine interaction and healthcare. Through material and structural innovations, FHEES combines the advantages of traditional stiff electronic devices and flexible electronic technology, enabling it to be worn conformally on the skin while retaining complex system functionality. FHEESs use multimodal sensing to enhance the identification accuracy of the wearer's motion modes, intentions, or health status, thus realizing more comprehensive physiological signal acquisition. However, the heterogeneous integration of soft and stiff components makes balancing comfort and performance in designing and implementing multimodal FHEESs challenging. Herein, multimodal FHEESs are first introduced in 2 types based on their different system structure: all-in-one and assembled, reflecting totally different heterogeneous integration strategies. Characteristics and the key design issues (such as interconnect design, interface strategy, substrate selection, etc.) of the 2 multimodal FHEESs are emphasized. Besides, the applications and advantages of the 2 multimodal FHEESs in recent research have been presented, with a focus on the control and medical fields. Finally, the prospects and challenges of the multimodal FHEES are discussed.

13.
Dev Med Child Neurol ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133768

RESUMO

AIM: To evaluate the effectiveness of magic-themed interventions in improving daily bimanual task performance in children with unilateral spastic cerebral palsy (CP) to and elucidate the variability in outcomes. METHOD: This systematic literature review searched databases including Embase, MEDLINE, Scopus, Cochrane Central, and CINAHL. Outcome measures selected for the meta-analysis included the Children's Hand-use Experience Questionnaire, its three subscales, and the Besta subscale C. The overall efficacy of magic-themed interventions was analysed using Hedges' g as the summary measure for these outcomes. Subgroup analysis compared the efficacy of different modes of training, and a meta-regression investigated the impact of training duration. RESULTS: Analyses of four studies involving 78 children showed magic-themed training significantly improved bimanual task performance (Hedges' g = 0.327, 95% confidence interval [CI] = 0.107-0.547, p = 0.004), especially in group settings (Hedges' g = 0.435, 95% CI = 0.176-0.693, p = 0.001), compared with non-significant gains from video interventions (Hedges' g = 0.041, 95% CI = -0.380 to 0.462, p = 0.850). Additionally, training duration positively correlated with performance gains (coefficient = 0.0076 per hour, p = 0.001). INTERPRETATION: Magic-themed training, especially through group sessions and extended durations, enhances bimanual skills in children with unilateral spastic CP.

14.
Food Chem ; 460(Pt 2): 140673, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39089012

RESUMO

In this study, a promising active food-packaging film of Gelatin/polyvinyl alcohol (GEL/PVA) integrated with doubly stabilized clove essential oil chitosome nanoparticles (CNP) was developed to maintain the freshness of marinated steaks. Results from the XRD and SEM experiments indicated excellent compatibility between the CNP and GEL/PVA matrix. Additionally, CNP was found to introduce more free hydroxyl groups, enhance the water retention and surface wettability of the CNP-GEL/PVA (C-G/P) film, and significantly reduce the swelling index from 963.78% to 495.11% (p < 0.05). Notably, the highest tensile strength and elongation at break (53.745 MPa and 46.536%, respectively) were achieved with the addition of 30% (v/v, based on the volume of gelatin) CNP; UVC was fully absorbed with 40% CNP; and films containing 60% CNP showed optimal inhibition of both Staphylococcus aureus and Escherichia coil, extending the shelf life of marinated steak from 3 to 7 days.

15.
Curr Neurovasc Res ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39092730

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is an aggressive type of brain tumor that is difficult to remove surgically. Research suggests that substances from saffron, namely crocetin and crocin, could be effective natural treatments, showing abilities to kill cancer cells. METHODS: Our study focused on evaluating the effects of crocetin on glioma using the U87 cell line. We specifically investigated how crocetin affects the survival, growth, and spread of glioma cells, exploring its impact at concentrations ranging from 75-150 µM. The study also included experiments combining crocetin with the chemotherapy drug Temozolomide (TMZ) to assess potential synergistic effects. RESULTS: Crocetin significantly reduced the viability, proliferation, and migration of glioma cells. It achieved these effects by decreasing the levels of Matrix Metallopeptidase 9 (MMP-9) and Ras homolog family member A (RhoA), proteins that are critical for cancer progression. Additionally, crocetin inhibited the formation of cellular structures necessary for tumor growth. It blocked multiple points of the Ak Strain Transforming (AKT) signaling pathway, which is vital for cancer cell survival. This treatment led to increased cell death and disrupted the cell cycle in the glioma cells. When used in combination with TMZ, crocetin not only enhanced the reduction of cancer cell growth but also promoted cell death and reduced cell replication. This combination therapy further decreased levels of high mobility group box 1 (HMGB1) and Receptor for Advanced Glycation End-products (RAGE), proteins linked to inflammation and tumor progression. It selectively inhibited certain pathways involved in the cellular stress response without affecting others. CONCLUSION: Our results underscore the potential of crocetin as a treatment for glioma. It targets various mechanisms involved in tumor growth and spread, offering multiple avenues for therapy. Further studies are essential to fully understand and utilize crocetin's benefits in treating glioma.

17.
Chem Commun (Camb) ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39099372

RESUMO

The increasing attention towards environmental quality, food safety, public security and medical diagnosis demands high requirements and standards for chemical sensors with merits of rapid response, high precision, long-term stability and reusability. In this case, a prominent innovation in sensory materials holds potential to realize new generations of chemical sensor technologies. Specifically, photonic crystals (PCs) as structured dielectric materials with spatially periodic ordered arrangements offer unique advantages in improving the sensing performance of chemical sensors. Consequently, the promising properties of PCs promote research on their implementation as an integral part of chemical sensors. This review highlights the integration of PCs into chemical sensors including a range of building blocks for the construction of PCs with versatile opal or opal inverse structural architectures and a delicate choice of surface functionality with associated sensing interfaces for target recognition and signal transduction. Subsequently, based on their synthesis and functionality, we focus on introducing the sensing principles of recent advances in PC-based chemical sensors, such as reflection spectra-based sensing, visual colorimetric sensing, fluorescence sensing, surface-enhanced Raman spectroscopy (SERS)-based sensing and other integrated sensing. Finally, the future prospects and challenges are discussed for the further improvement of PC-based chemical sensors.

18.
Sleep Med ; 122: 45-50, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39121823

RESUMO

BACKGROUND: The medullary nucleus of solitary tract (NTS) and its afferents of vagus nerve have long been investigated in regulation of cortical activity and sleep promotion. However, the underlying neural circuit by which the NTS regulates electroencephalogram (EEG) and sleep remain unclear. As the NTS has a strong projection to the pontine arousal site, the parabrachial nucleus (PB), we proposed the NTS via the pontine parabrachial nucleus (PB) regulates cortical activity and sleep. METHODS: We bilaterally and directly stimulated the NTS neurons by chemogenetic approach and NTS terminals in the PB by optogenetic approach and examined changes in EEG and sleep in rats. RESULTS: Opto- and chemo-stimulation of the NTS and NTS-PB pathway altered neither sleep amounts nor patterns; however, both stimulations consistently increased EEG delta (0.5-4.0 Hz) EEG power during non-rapid-eye-movement (NREM) sleep and alpha-beta (10-30 Hz) EEG power during wake and REM sleep. CONCLUSION: Our results indicate that the NTS via its projections to the PB synchronizes low frequency EEG during NREM sleep and high frequency EEG during wake and REM sleep. This pathway may serve the neural foundation for the vagus nerve stimulation (VNS) treating cortical disorders.

19.
Biomed Mater ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39121887

RESUMO

Guided bone regeneration (GBR) membranes play an important role in oral bone regeneration. However, enhancing their bone regeneration potential and antibacterial properties is crucial. Herein, silk fibroin/polycaprolactone core-shell nanofibers loaded with epigallocatechin gallate (EGCG) were prepared using emulsion electrospinning. The nanofibrous membranes were characterized via scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, water contact angle measurement, mechanical properties testing, drug release kinetics, and 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) free radical scavenging assay. Mouse pre-osteoblast MC3T3-E1 cells were used to assess the biological characteristics, cytocompatibility, and osteogenic differentiation potential of the nanofibrous membrane. Additionally, the antibacterial properties against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were evaluated. The nanofibers prepared by emulsion electrospinning exhibited a stable core-shell structure with a smooth and continuous surface. The tensile strength of the silk fibroin/polycaprolactone membrane loaded with EGCG was 3.88 ± 0.15 Mpa, the water contact angle was 50°, and the DPPH clearance rate at 24 h was 81.73 ± 0.07%. The EGCG release rate of membranes prepared by emulsion electrospinning was reduced by 12% within 72 h compared to that of membranes prepared via traditional electrospinning. In vitro experiments indicate that the core-shell membranes loaded with EGCG demonstrated good cell compatibility and promoted adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 cells. Furthermore, the EGCG-loaded membranes exhibited inhibitory effects on E. coli and S. aureus. These findings indicate that core-shell nanofibrous membranes encapsulated with EGCG prepared using emulsion electrospinning possess good antioxidant, osteogenic, and antibacterial properties, making them potential candidates for research in GBR materials.

20.
Anal Chim Acta ; 1319: 342961, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39122274

RESUMO

BACKGROUND: Iron ion (Fe3+) is essential for the environment and human health. Detecting Fe3+ in water is crucial, making high-performance detection a key objective. Lanthanide metal-organic frameworks with abundant functional sites have been deemed a promising fluorescence sensor for Fe3+ detection. Currently, most metal-organic framework-based sensors for Fe3+ detection have cumbersome and time-consuming synthesis procedures and long detection times, which greatly limits their practical application. This study aims to construct a hybrid lanthanide metal-organic frameworks-based fluorescence sensor for Fe3+ detection that promises simple and rapid iron ion quantification in water. RESULTS: A novel hybrid lanthanide metal-organic frameworks (ECTMNs) was synthesized in one step using a solvothermal method with only 4 h. The frameworks comprise two metal ions, cerium and europium, serving as metal centers, and 4,4,4,4-(Porphine-5,10,15,20-tetrayl) tetrakis (TCPP) as an organic ligand. With the addition of Fe3+, the host-guest reaction occurred between Fe3+ and ECTMNs probe, leading to the gradual fluorescence burst of ECTMNs probe. A strong linear correlation between ECTMNs fluorescence intensity and Fe3+ concentration (1-90 µM) makes it a reliable sensor for Fe3+ monitoring with a detection limit of 0.3 µM. Moreover, the method was used to analyze real samples (tap water and river water), showing good recoveries (92-98 %) and low relative standard deviations (3.96-6.11 %), making it a promising option for rapidly detecting Fe3+. SIGNIFICANCE AND NOVELTY: A rapid synthesis protocol for hybrid lanthanide metal-organic frameworks is proposed in this study. The obtained ECTMNs exhibits good water solubility, high stability, and specificity for Fe3+. Based on ECTMNs, an innovative fluorescence sensor is established for selectively detecting Fe3+ in water, which is a simple operation method with a low detection limit and short sensing time. It provides a novel method for accurately and rapidly detecting Fe3+ in environmental pollution and water safety monitoring.

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