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1.
J Orthop Surg Res ; 19(1): 460, 2024 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-39095815

RÉSUMÉ

PURPOSE: Both vitamin C and D deficiencies are extremely common in clinical practice, especially in elderly population. Unfortunately, the role of vitamin C deficiency in osteoporosis related consequences is often neglected. The aim of the present study is to analyse if combined vitamin C and D deficiency would have an association with bone mineral density (BMD) and osteoporotic vertebral fracture (OVF). METHODS: Ninety-nine post-menopausal female patients admitted in the department of spine surgery of third affiliated hospital of Sun Yat-sen University were enrolled in the study. The participants were divided into four groups; vitamin D deficiency alone (comparator group), vitamin C deficiency alone and combined vitamin C and D deficiency as experimental group. The levels of vitamin C, vitamin D, calcium, phosphorous, BMD and condition of OVF were analysed. RESULTS: There were statistically significant differences between the groups in terms of vitamin C and D levels. In terms of lumbar BMD, significant differences were observed between vitamin D deficiency alone and combined vitamin C and D deficiency. Only the combined vitamin C and D deficiency had a significant negative association with lumbar BMD and T-score. Similarly, combined vitamin C and D deficiency had a significant positive association with lumbar osteoporosis. None of the groups had any significant association with OVF. Combined vitamin C and D deficiency was found to be significantly associated with lower lumbar BMD and osteoporosis. CONCLUSION: Combined vitamin C and D deficiency results in lower bone mineral density and higher risk of osteoporosis. We believe that existence of deficiencies of both vitamins could have a synergistic effect. Therefore, we recommend that vitamin C and D should be routinely measured in clinical practice.


Sujet(s)
Carence en acide ascorbique , Densité osseuse , Fractures du rachis , Carence en vitamine D , Humains , Femelle , Carence en vitamine D/complications , Fractures du rachis/étiologie , Sujet âgé , Carence en acide ascorbique/complications , Adulte d'âge moyen , Fractures ostéoporotiques/étiologie , Vertèbres lombales/imagerie diagnostique , Acide ascorbique/administration et posologie , Sujet âgé de 80 ans ou plus
2.
Neuroimage ; 297: 120722, 2024 Jul 04.
Article de Anglais | MEDLINE | ID: mdl-38971483

RÉSUMÉ

Previous studies have shown that major depressive disorder (MDD) patients exhibit structural and functional impairments, but few studies have investigated changes in higher-order coupling between structure and function. Here, we systematically investigated the effect of MDD on higher-order coupling between structural connectivity (SC) and functional connectivity (FC). Each brain region was mapped into embedding vector by the node2vec algorithm. We used support vector machine (SVM) with the brain region embedding vector to distinguish MDD patients from health controls (HCs) and identify the most discriminative brain regions. Our study revealed that MDD patients had decreased higher-order coupling in connections between the most discriminative brain regions and local connections in rich-club organization and increased higher-order coupling in connections between the ventral attentional network and limbic network compared with HCs. Interestingly, transcriptome-neuroimaging association analysis demonstrated the correlations between regional rSC-FC coupling variations between MDD patients and HCs and α/ß-hydrolase domain-containing 6 (ABHD6), ß 1,3-N-acetylglucosaminyltransferase-9(ß3GNT9), transmembrane protein 45B (TMEM45B), the correlation between regional dSC-FC coupling variations and retinoic acid early transcript 1E antisense RNA 1(RAET1E-AS1), and the correlations between regional iSC-FC coupling variations and ABHD6, ß3GNT9, katanin-like 2 protein (KATNAL2). In addition, correlation analysis with neurotransmitter receptor/transporter maps found that the rSC-FC and iSC-FC coupling variations were both correlated with neuroendocrine transporter (NET) expression, and the dSC-FC coupling variations were correlated with metabotropic glutamate receptor 5 (mGluR5). Further mediation analysis explored the relationship between genes, neurotransmitter receptor/transporter and MDD related higher-order coupling variations. These findings indicate that specific genetic and molecular factors underpin the observed disparities in higher-order SC-FC coupling between MDD patients and HCs. Our study confirmed that higher-order coupling between SC and FC plays an important role in diagnosing MDD. The identification of new biological evidence for MDD etiology holds promise for the development of innovative antidepressant therapies.

3.
Cell Rep Methods ; 4(7): 100810, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-38981475

RÉSUMÉ

In single-cell RNA sequencing (scRNA-seq) studies, cell types and their marker genes are often identified by clustering and differentially expressed gene (DEG) analysis. A common practice is to select genes using surrogate criteria such as variance and deviance, then cluster them using selected genes and detect markers by DEG analysis assuming known cell types. The surrogate criteria can miss important genes or select unimportant genes, while DEG analysis has the selection-bias problem. We present Festem, a statistical method for the direct selection of cell-type markers for downstream clustering. Festem distinguishes marker genes with heterogeneous distribution across cells that are cluster informative. Simulation and scRNA-seq applications demonstrate that Festem can sensitively select markers with high precision and enables the identification of cell types often missed by other methods. In a large intrahepatic cholangiocarcinoma dataset, we identify diverse CD8+ T cell types and potential prognostic marker genes.


Sujet(s)
Analyse sur cellule unique , Analyse sur cellule unique/méthodes , Humains , Analyse de regroupements , Analyse de profil d'expression de gènes/méthodes , Analyse de séquence d'ARN/méthodes , Marqueurs biologiques tumoraux/génétique , Marqueurs biologiques tumoraux/métabolisme , Lymphocytes T CD8+/métabolisme , Cholangiocarcinome/génétique , Cholangiocarcinome/anatomopathologie , Marqueurs génétiques/génétique
4.
Rapid Commun Mass Spectrom ; 38(19): e9872, 2024 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-39044122

RÉSUMÉ

RATIONALE: Eucommia cortex is the core herb in traditional Chinese medicine preparations for the treatment of osteoporosis. Pinoresinol diglucoside (PDG), the quality control marker and the key pharmacodynamic component in Eucommia cortex, has attracted global attention because of its definite effects on osteoporosis. However, the in vivo metabolic characteristics of PDG and its anti-osteoporotic mechanism are still unclear, restricting its development and application. METHODS: Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to analyze the metabolic characteristics of PDG in rats, and its anti-osteoporosis targets and mechanism were predicted using network pharmacology. RESULTS: A total of 51 metabolites were identified or tentatively characterized in rats after oral administration of PDG (10 mg/kg/day), including 9 in plasma, 28 in urine, 13 in feces, 10 in liver, 4 in heart, 3 in spleen, 11 in kidneys, and 5 in lungs. Furan-ring opening, dimethoxylation, glucuronidation, and sulfation were the main metabolic characteristics of PDG in vivo. The potential mechanism of PDG against osteoporosis was predicted using network pharmacology. PDG and its metabolites could regulate BCL2, MARK3, ALB, and IL6, involving PI3K-Akt signaling pathway, estrogen signaling pathway, and so on. CONCLUSIONS: This study was the first to demonstrate the metabolic characteristics of PDG in vivo and its potential anti-osteoporosis mechanism, providing the data for further pharmacological validation of PDG in the treatment of osteoporosis.


Sujet(s)
Lignanes , Pharmacologie des réseaux , Ostéoporose , Rat Sprague-Dawley , Animaux , Lignanes/pharmacologie , Lignanes/métabolisme , Ostéoporose/traitement médicamenteux , Ostéoporose/métabolisme , Rats , Chromatographie en phase liquide à haute performance/méthodes , Mâle , Médicaments issus de plantes chinoises/pharmacologie , Médicaments issus de plantes chinoises/administration et posologie , Médicaments issus de plantes chinoises/métabolisme , Médicaments issus de plantes chinoises/composition chimique , Métabolomique/méthodes , Glucosides/pharmacologie , Métabolome/effets des médicaments et des substances chimiques , Spectrométrie de masse/méthodes
5.
Nanomedicine ; 62: 102773, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38960364

RÉSUMÉ

To address the adverse side effects associated with systemic high-dose methylprednisolone (MP) therapy for acute spinal cord injury (SCI), we have developed a N-2-hydroxypropyl methacrylamide copolymer-based MP prodrug nanomedicine (Nano-MP). Intravenous Nano-MP selectively targeted to the inflamed SCI lesion and significantly improved neuroprotection and functional recovery after acute SCI. In the present study, we comprehensively assessed the potential adverse side effects associated with the treatment in the SCI rat models, including reduced body weight and food intake, impaired glucose metabolism, and reduced musculoskeletal mass and integrity. In contrast to free MP treatment, intravenous Nano-MP after acute SCI not only offered superior neuroprotection and functional recovery but also significantly mitigated or even eliminated the aforementioned adverse side effects. The superior safety features of Nano-MP observed in this study further confirmed the clinical translational potential of Nano-MP as a highly promising drug candidate for better clinical management of patients with acute SCI.

6.
Article de Anglais | MEDLINE | ID: mdl-39041590

RÉSUMÉ

Recently, the folate receptor (FR) has become an exciting target for the diagnosis of FR-positive malignancies. Nevertheless, suboptimal in vivo pharmacokinetic properties, particularly high uptake in the renal and hepatobiliary systems, are important limiting factors for the clinical translation of most FR-based radiotracers. In this study, we developed a novel 18F-labeled FR-targeted positron emission tomography (PET) tracer [18F]AlF-NOTA-Asp2-PEG2-Folate modified with a hydrophilic linker (-Asp2-PEG2) to optimize its pharmacokinetic properties and conducted a comprehensive preclinical assessment. The [18F]AlF-NOTA-Asp2-PEG2-Folate was manually synthesized within 30 min with a non-decay-corrected radiochemical yield of 16.3 ± 2.0% (n = 5). Among KB cells, [18F]AlF-NOTA-Asp2-PEG2-Folate exhibited high specificity and affinity for FR. PET/CT imaging and biodistribution experiments in KB tumor-bearing mice showed decent tumor uptake (1.7 ± 0.3% ID/g) and significantly decreased uptake in kidneys and liver (22.2 ± 2.1 and 0.3 ± 0.1% ID/g at 60 min p.i., respectively) of [18F]AlF-NOTA-Asp2-PEG2-Folate, compared to the known tracer [18F]AlF-NOTA-Folate (78.6 ± 5.1 and 5.3 ± 0.5 % ID/g at 90 min p.i., respectively). The favorable properties of [18F]AlF-NOTA-Asp2-PEG2-Folate, including its efficient synthesis, decent tumor uptake, relatively low renal uptake, and rapid clearance from most normal organs, portray it as a promising PET tracer for FR-positive tumors.

7.
Neuropharmacology ; : 110083, 2024 Jul 21.
Article de Anglais | MEDLINE | ID: mdl-39043267

RÉSUMÉ

Neuronal cell demise represents a prevalent occurrence throughout the advancement of Alzheimer's disease (AD). However, the mechanism of triggering the death of neuronal cells remains unclear. Its potential mechanisms include aggregation of soluble amyloid-beta (Aß) to form insoluble amyloid plaques, abnormal phosphorylation of tau protein and formation of intracellular neurofibrillary tangles (NFTs), neuroinflammation, ferroptosis, oxidative stress, liquid-liquid phase separation (LLPS) and metal ion disorders. Among them, ferroptosis is an iron-dependent lipid peroxidation-driven cell death and emerging evidences have demonstrated the involvement of ferroptosis in the pathological process of AD. The sensitivity to ferroptosis is tightly linked to numerous biological processes. Moreover, emerging evidences indicate that LLPS has great impacts on regulating human health and diseases, especially AD. Soluble Aß can undergo LLPS to form liquid-like droplets, which can lead to the formation of insoluble amyloid plaques. Meanwhile, tau has a high propensity to condensate via the mechanism of LLPS, which can lead to the formation of NFTs. In this review, we summarize the most recent advancements pertaining to LLPS and ferroptosis in AD. Our primary focus is on expounding the influence of Aß, tau protein, iron ions, and lipid oxidation on the intricate mechanisms underlying ferroptosis and LLPS within the domain of AD pathology. Additionally, we delve into the intricate cross-interactions that occur between LLPS and ferroptosis in the context of AD. Our findings are expected to serve as a theoretical and experimental foundation for clinical research and targeted therapy for AD.

8.
ACS Nano ; 18(29): 18880-18888, 2024 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-38991129

RÉSUMÉ

Emitting light toward on-demand directions is important for various optoelectronic applications, such as optical communication, displaying, and ranging. However, almost all existing directional emitters are assemblies of passive optical antennae and external light sources, which are usually bulky and fragile and show unendurable loss of light power. Here we theoretically propose and experimentally demonstrate a conceptual design of a directional emitter, by using a single surface-emitting laser source itself to achieve dynamically controlled beam steering. The laser is built on photonic crystals that operate near the band edges in the continuum. By shrinking laser sizes to tens-of-wavelength, the optical modes quantize in three-dimensional momentum space, and each of them directionally radiates toward the far-field. Further utilizing the luminescence spectrum shifting effect under current injection, we consecutively select a sequence of modes into lasing action and show the laser maintaining single-mode operation with line widths at a minimum of 1.8 MHz and an emitting power of ∼10 milliwatts, and we demonstrate fast beam steering across a range of 3.2° × 4° on a time scale of 500 ns. Our work proposes a method for on-chip active beam steering for the development of automotive, industrial, and robotic applications.

9.
BMC Musculoskelet Disord ; 25(1): 482, 2024 Jun 19.
Article de Anglais | MEDLINE | ID: mdl-38898434

RÉSUMÉ

BACKGROUND: The associations between serum uric acid and osteoporosis or osteopenia remain controversial, and few studies have explored whether BMI acts as a mediators in the association between the SUA and OP/ osteopenia. OBJECTIVE: To explore the relationship between serum uric acid and osteoporosis or osteopenia among US adults. METHODS: A cross-sectional study was conducted to examine the association between serum uric acid and osteoporosis or osteopenia from four cycles of NHANES. Binary logistic regression models and restricted cubic spline models were used to evaluate the association between serum uric acid and osteoporosis or osteopenia, and interaction analysis was used to test the differences between subgroups. Mediation analysis was utilized to investigate whether BMI acts as a mediator in the association between SUA and OP/ osteopenia. RESULTS: 12581 participants aged ≥ 18 years were included. A U-shape nonlinear relationship between SUA and osteoporosis or osteopenia in all people was found (P < 0.0001, P for nonlinear = 0.0287). There were significant interactions in age subgroups (P for interaction = 0.044), sex subgroups (P for interaction = 0.005), and BMI subgroups (P for interaction = 0.017). We further assessed the subgroups and found the optimal range of serum uric acid levels with a lower risk of osteoporosis or osteopenia was 357-535 µmol/L in males, 327-417 µmol/L in people aged ≥ 50 years, above 309 µmol/L in people aged < 50 years, 344-445 µmol/L in people with BMI ≥ 30, and above 308 µmol/L in people with BMI < 30. BMI fully mediated the association of SUA and OP/osteopenia, with a value of -0.0024(-0.0026--0.0021). These results were robust in sensitivity analyses. CONCLUSIONS: A complicated relationship between SUA and bone health in different populations was observed. Maintaining SUA within a specific range may be beneficial to bone health. In addition, BMI may play an important role in the association between SUA and bone health, but considering the limitations of this study, further prospective research is required.


Sujet(s)
Indice de masse corporelle , Maladies osseuses métaboliques , Enquêtes nutritionnelles , Ostéoporose , Acide urique , Humains , Études transversales , Mâle , Acide urique/sang , Femelle , Adulte d'âge moyen , Ostéoporose/sang , Ostéoporose/épidémiologie , Adulte , Maladies osseuses métaboliques/sang , Maladies osseuses métaboliques/épidémiologie , Maladies osseuses métaboliques/diagnostic , Sujet âgé , États-Unis/épidémiologie , Densité osseuse/physiologie , Jeune adulte , Facteurs de risque
10.
J Phys Chem Lett ; 15(25): 6568-6574, 2024 Jun 27.
Article de Anglais | MEDLINE | ID: mdl-38885430

RÉSUMÉ

Optical processing of single plasmonic nanoparticles reinvents the way of high-density information storage, high-performance sensing, and high-definition displays. However, such laser-fabricated nanoplasmonics with well-defined hot spots remain elusive due to the diffraction limit of light. Here we show Au nanoparticle (NP) decorated nanopores can be facilely generated with photothermal splitting of single Au NPs embedded in a silica matrix. The extremely high local temperature induced by plasmonic heating renders gradients of the temperature and surface tension around the Au NP, which drives the nanoscale thermophoretic and Marangoni flow of molten Au/silica. As a result, a nanopore decorated with fragmented Au NPs is formed in the silica film, which presents much stronger surface-enhanced Raman scattering as compared to a single Au NP due to the emergence of hot spots. This strategy can be used to generate plasmonic nanopores of various sizes in the silicon nitride (SiNx) films, which further transforms into nanonets at ambient conditions via light-induced reconstruction of silicon nitride membrane. These nanonets can serve as a robust platform for single particle trapping and analysis.

11.
Angew Chem Int Ed Engl ; : e202411018, 2024 Jun 27.
Article de Anglais | MEDLINE | ID: mdl-38932606

RÉSUMÉ

The multiple mortise-and-tenon joint parts are the core factors to provide the structural stability and diversity of Chinese Luban locks, however, constructing such structures is very challenging. Herein, single crystals of covalent organic nanoribbon (named CityU-27) are prepared through the assembly of hexahydroxytriphenylene (HHTP), 4,4'-Vinylenedipyridine (BYE), and phenylboronic acid (BA) together via dative boron←nitrogen (B←N) bonds. The single crystal X-ray diffraction analysis indicates that CityU-27 has covalent organic nanoribbon, where each nanoribbon forms multiple and tight π-π interactions with four neighboring others to generate a Luban lock-like configuration. CityU-27 has been demonstrated as an efficient photocatalyst in a one-pot tandem reaction of hydrogen evolution reaction (HER) and semi-hydrogenation reaction of alkynes in series to produce olefins without any additional photosensitizers and co-catalysts (metal-free).

12.
Nanomedicine ; 60: 102761, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38871068

RÉSUMÉ

To date, no therapy has been proven to be efficacious in fully restoring neurological functions after spinal cord injury (SCI). Systemic high-dose methylprednisolone (MP) improves neurological recovery after acute SCI in both animal and human. MP therapy remains controversial due to its modest effect on functional recovery and significant adverse effects. To overcome the limitation of MP therapy, we have developed a N-(2-hydroxypropyl) methacrylamide copolymer-based MP prodrug nanomedicine (Nano-MP) that can selectively deliver MP to the SCI lesion when administered systemically in a rat model of acute SCI. Our in vivo data reveal that Nano-MP is significantly more effective than free MP in attenuating secondary injuries and neuronal apoptosis. Nano-MP is superior to free MP in improving functional recovery after acute SCI in rats. These data support Nano-MP as a promising neurotherapeutic candidate, which may provide potent neuroprotection and accelerate functional recovery with improved safety for patients with acute SCI.


Sujet(s)
Méthylprednisolone , Nanomédecine , Neuroprotecteurs , Rat Sprague-Dawley , Récupération fonctionnelle , Traumatismes de la moelle épinière , Animaux , Traumatismes de la moelle épinière/traitement médicamenteux , Traumatismes de la moelle épinière/anatomopathologie , Méthylprednisolone/pharmacologie , Méthylprednisolone/administration et posologie , Méthylprednisolone/usage thérapeutique , Rats , Récupération fonctionnelle/effets des médicaments et des substances chimiques , Neuroprotecteurs/pharmacologie , Neuroprotecteurs/composition chimique , Neuroprotecteurs/usage thérapeutique , Systèmes de délivrance de médicaments , Neuroprotection/effets des médicaments et des substances chimiques
13.
Langmuir ; 40(24): 12767-12777, 2024 Jun 18.
Article de Anglais | MEDLINE | ID: mdl-38845086

RÉSUMÉ

In this study, we prepared a multicolor structural-fluorescent CdS-PEGDA photonic crystal hydrogel (SFC-CPH) with a dual display mode, which has two different optical states: structural color mode and fluorescent color mode. SFC-CPH displays structural color mode under visible light and fluorescent color mode under ultraviolet light. Initially, monodisperse CdS colloidal particles were synthesized via a hydrothermal method, leading to the self-assembly of a photonic crystal template. The high refractive index of CdS contributes to the photonic crystals' low-angle dependence and vivid structural colors. Then, a variety of fluorescent molecules were doped into poly(ethylene glycol) diacrylate (PEGDA) hydrogel and combined with photonic crystals with distinct structural colors to prepare three distinct colors of SFC-CPH. We also investigated the optical characteristics and surface properties of these photonic crystal hydrogels. Based on these dual-mode display characteristics, we designed several dual-mode display patterns and a method for information encoding. The unique property of this photonic crystal hydrogel material suggests its substantial potential for applications in information storage, security, and encoding, offering innovative avenues in the realm of information display.

14.
Andrology ; 2024 Jun 27.
Article de Anglais | MEDLINE | ID: mdl-38937909

RÉSUMÉ

BACKGROUND: Erectile dysfunction (ED) is prevalent not only among older males but also in younger. The physical activity has been considered a potential protective factor against ED. However, there is a lack of comprehensive research on the impact of exercise interventions specifically on ED patients. OBJECTIVES: This study aimed to assess the effectiveness of the physical activity in addressing ED symptoms among adult males, without the use of the phosphodiesterase-5 inhibitors (PDE5i) therapy. Additionally, subgroup analysis was performed to evaluate the effects of different exercise modes. METHODS: Employing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a systematic literature search. A registered protocol is available at PROSPERO (CRD42023441717). Our search spanned PubMed, Web of Science, Embase, and Cochrane Library, with data collection ending on 11 April 2024. The Cochrane Risk of Bias tool was applied by two independent authors to assess randomized controlled trial (RCT) quality. The primary endpoint was determined as the International Index of Erectile Function (IIEF) scores. RESULTS: A total of seven RCTs were included. Utilizing a random-effects model, the estimated standardized mean difference (SMD) was 0.69 (95% confidence interval [CI] 0.37 to 1.02, p < 0.0001) for the overall impact of the physical activity. Subgroup analysis revealed SMDs of 0.81 (95% CI 0.56 to 1.06; p < 0.00001) for aerobic training alone. However, no significant improvement was observed with pelvic floor muscle training (PFMT) (SMD 0.03; 95% CI -0.68 to 0.75; p = 0.93) and a combination of aerobic and resistance training (SMD 0.84; 95% CI -0.41 to 2.09; p = 0.19) CONCLUSION: The findings of this study highlight a significant improvement in the erectile function following exercise interventions for adult men with ED, who are not receiving the PDE5i therapy, especially in conducting aerobic training alone. However, PFMT and a combination of aerobic and resistance training did not show significant improvements in erectile function from this study.

15.
Anal Chem ; 96(21): 8528-8533, 2024 05 28.
Article de Anglais | MEDLINE | ID: mdl-38728651

RÉSUMÉ

In the realm of nanopore sensor technology, an enduring challenge lies in achieving the discerning detection of small biomolecules with a sufficiently high signal-to-noise ratio. This study introduces a method for reliably quantifying the concentration of target small molecules, utilizing tetrahedral DNA nanostructures as surrogates for the captured molecules through a magnetic-bead-based competition substitution mechanism. Magnetic Fe3O4-DNA tetrahedron nanoparticles (MNPs) are incorporated into a nanopore electrochemical system for small-molecule sensing. In the presence of the target, the DNA tetrahedron, featuring an aptamer tail acting as a molecular carrier, detaches from the MNPs due to aptamer deformation. Following removal of the MNPs, the DNA tetrahedron bound to the target traversed the nanopore by applying a positive potential. This approach exhibits various advantages, including heightened sensitivity, selectivity, an improved signal-to-noise ratio (SNR), and robust anti-interference capabilities. Our findings demonstrate that this innovative methodology has the potential to significantly enhance the sensing of various small-molecule targets by nanopores, thereby advancing the sensitivity and dynamic range. This progress holds promise for the development of precise clinical diagnostic tools.


Sujet(s)
Aptamères nucléotidiques , ADN , Nanopores , Nanostructures , ADN/composition chimique , ADN/analyse , Aptamères nucléotidiques/composition chimique , Nanostructures/composition chimique , Techniques électrochimiques/méthodes , Techniques de biocapteur/méthodes
16.
Adv Sci (Weinh) ; 11(28): e2402645, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38738739

RÉSUMÉ

The photocatalytic reduction of CO2 represents an environmentally friendly and sustainable approach for generating valuable chemicals. In this study, a thiophene-modified highly conjugated asymmetric covalent triazine framework (As-CTF-S) is developed for this purpose. Significantly, single-component intramolecular energy transfer can enhance the photogenerated charge separation, leading to the efficient conversion of CO2 to CO during photocatalysis. As a result, without the need for additional photosensitizers or organic sacrificial agents, As-CTF-S demonstrates the highest photocatalytic ability of 353.2 µmol g-1 and achieves a selectivity of ≈99.95% within a 4 h period under visible light irradiation. This study provides molecular insights into the rational control of charge transfer pathways for high-efficiency CO2 photoreduction using single-component organic semiconductor catalysts.

17.
Glob Chang Biol ; 30(5): e17350, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38804101

RÉSUMÉ

With over one-third of terrestrial net primary productivity transferring to the litter layer annually, the carbon release from litter serves as a crucial valve in atmospheric carbon dioxide concentrations. However, few quantitative global projections of litter carbon release rate in response to climate change exist. Here, we combined a global foliar litter carbon release dataset (8973 samples) to generate spatially explicitly estimates of the response of their residence time (τ) to climate change. Results show a global mean litter carbon release rate ( k $$ k $$ ) of 0.69 year-1 (ranging from 0.09-5.6 year-1). Under future climate scenarios, global mean τ is projected to decrease by a mean of 2.7% (SSP 1-2.6) and 5.9% (SSP 5-8.5) during 2071-2100 period. Locally, the alleviation of temperature and moisture restrictions corresponded to obvious decreases in τ in cold and arid regions, respectively. In contract, τ in tropical humid broadleaf forests increased by 4.6% under SSP 5-8.5. Our findings highlight the vegetation type as a powerful proxy for explaining global patterns in foliar litter carbon release rates and the role of climate conditions in predicting responses of carbon release to climate change. Our observation-based estimates could refine carbon cycle parameterization, improving projections of carbon cycle-climate feedbacks.


Sujet(s)
Carbone , Changement climatique , Feuilles de plante , Feuilles de plante/métabolisme , Carbone/métabolisme , Cycle du carbone , Forêts , Dioxyde de carbone/métabolisme , Dioxyde de carbone/analyse , Réchauffement de la planète , Arbres/métabolisme
18.
Ultrason Sonochem ; 107: 106918, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38772313

RÉSUMÉ

In this research, the extraction process of polysaccharides from Pithecellobium clypearia Benth (PCBPs) was optimized using dual-frequency ultrasound-assisted extraction (DUAE). The biological activities of PCBPs were investigated by in vitro antioxidant, hypoglycemic, and anti-hyperlipidemic assay. High-performance anion-exchange chromatography, high-performance gel permeation chromatography, SEM, UV-Vis spectroscopy, and FT-IR spectra were used to analyze the monosaccharide composition, molecular weight, microscopic morphology, and characteristic structure of PCBPs. The results showed that the maximum extraction rate of PCBPs was 9.90 ± 0.16% when the ultrasonic time was 8 min, the liquid-to-material ratio was 32 mL/g, and the ultrasonic power was 510 W. The PCBPs also possessed excellent in vitro antioxidant, hypoglycemic, and anti-hyperlipidemic activities. In addition, the average molecular weight of PCBPs was 15.07 kDa. PCBPs consisted of rhamnose, arabinose, galactose, glucose, xylose, mannose, and glucuronic acid, with the molar ratios of 11.07%, 18.54%, 48.17%, 10.44%, 4.62%, 4.96%, and 2.20%, respectively. Moreover, the results of SEM showed that PCBPs mainly showed a fine spherical mesh structure. The above studies provided a valuable theoretical basis for the subsequent in-depth study of PCBPs.


Sujet(s)
Antioxydants , Hypoglycémiants , Hypolipémiants , Polyosides , Ondes ultrasonores , Antioxydants/pharmacologie , Antioxydants/composition chimique , Antioxydants/isolement et purification , Polyosides/composition chimique , Polyosides/isolement et purification , Polyosides/pharmacologie , Hypoglycémiants/pharmacologie , Hypoglycémiants/composition chimique , Hypoglycémiants/isolement et purification , Hypolipémiants/pharmacologie , Hypolipémiants/composition chimique , Hypolipémiants/isolement et purification , Fractionnement chimique/méthodes , Fabaceae/composition chimique , Masse moléculaire , Animaux
19.
J Pharm Biomed Anal ; 247: 116257, 2024 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-38815520

RÉSUMÉ

Zhi-Ke-Bao pills (ZKB), a traditional Chinese medicine preparation composed of 13 herbs, is generally used to treat cough caused by external wind cold, phlegm, etc in clinical applications, and it plays a core role in relieving cough caused by COVID-19 and influenza in China. Till now, the understanding of its chemical constituents was dramatically limited due to its chemical complexity, restricting its clinical application or development. In this work, a developed ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF MS) method, a targeted and non-targeted strategy and network pharmacology were used to comprehensively characterize the chemical compositions in ZKB and predict its mechanism against cough. A total of 164 compounds (148 targeted compounds and 16 non-targeted ones) were identified or tentatively characterized in ZKB, including 65 flavonoids, 25 alkaloids, 19 organic acids, 41 saponins, 9 coumarins, 2 phenylpropanoids, 2 anthraquinones, and 1 other types. Among them, 37 compounds were unambiguously identified by comparison to reference standards. Meanwhile, the fragmentation behaviors of five main chemical structure types were also summarized. 309 targets and two core signaling pathways of ZKB against cough were predicted by network pharmacology, including MAPK and PI3K-Akt signaling pathways. It was the first time to characterize the chemical compounds of ZKB and reveal its potential mechanism against cough, providing the material basis for further quality control or pharmacodynamic evaluation of ZKB.


Sujet(s)
Toux , Médicaments issus de plantes chinoises , Pharmacologie des réseaux , Médicaments issus de plantes chinoises/composition chimique , Médicaments issus de plantes chinoises/pharmacologie , Médicaments issus de plantes chinoises/analyse , Chromatographie en phase liquide à haute performance/méthodes , Toux/traitement médicamenteux , Humains , Spectrométrie de masse/méthodes , Médecine traditionnelle chinoise/méthodes , Antitussifs/pharmacologie , Antitussifs/composition chimique , Antitussifs/analyse , Traitements médicamenteux de la COVID-19 , Alcaloïdes/analyse , Alcaloïdes/composition chimique , Alcaloïdes/pharmacologie
20.
J Thorac Dis ; 16(4): 2472-2481, 2024 Apr 30.
Article de Anglais | MEDLINE | ID: mdl-38738243

RÉSUMÉ

Background: Esophageal malignancies have a high morbidity rate worldwide, and minimally invasive surgery has emerged as the primary approach for treating esophageal cancer. In recent years, there has been increasing discussion about the potential of employing inflatable mediastinoscopic and laparoscopic approaches as an option for esophagectomy. Building on the primary modification of the inflatable mediastinoscopic technique, we introduced a secondary modification to further minimize surgical trauma. Methods: We conducted a retrospective analysis of patients who underwent inflatable mediastinoscopy combined with laparoscopic esophagectomy at the Second Affiliated Hospital of Naval Medical University from March 2020 to March 2023. The patients were allocated to the following two groups: the traditional (primary modification) group, and the secondary modification group. Operation times, intraoperative bleeding, and postoperative complications were compared between the groups. Results: The procedure was successfully performed in all patients, and conversion to open surgery was not required in any case. There were no statistically significant differences in the surgical operation time, intraoperative bleeding, number of dissected lymph nodes, and rate of postoperative anastomotic leakage between the two groups. However, a statistically significant difference was observed in the length of the mobilized esophagus between the two groups. The mobilization of esophagus to the level of diaphragmatic hiatus via the cervical incision was successfully achieved in more patients in the secondary modification group than the primary modification group. Conclusions: Inflatable mediastinoscopy combined with single-incision plus one-port laparoscopic esophagectomy is a safe and effective surgical procedure. The use of a 5-mm flexible endoscope, ultra-long five-leaf forceps, and LigaSure Maryland forceps facilitates esophageal mobilization and lymph node dissection through a single cervical incision.

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