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1.
Am J Chin Med ; : 1-36, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716620

RESUMO

Schisandra chinensis (S. chinensis) has a long history as a traditional Chinese medicine that is astringent, beneficial to vital energy, tonifies the kidney, tranquilizes the heart, etc. Significantly, Schisandrol A (SA) is extracted from S. chinensis and shows surprising and satisfactory biological activity, including anti-inflammatory, hepatoprotective, cardiovascular protection, and antitumor properties, among others. SA has a more pronounced protective effect on central damaged nerves among its numerous pharmacological effects, improving neurodegenerative diseases such as Alzheimer's and Parkinson's through the protection of damaged nerve cells and the enhancement of anti-oxidant capacity. Pharmacokinetic studies have shown that SA has a pharmacokinetic profile with a rapid absorption, wide distribution, maximal concentration in the liver, and primarily renal excretion. However, hepatic and intestinal first-pass metabolism can affect SA's bioavailability. In addition, the content of SA, as an index component of S. chinensis Pharmacopoeia, should not be less than 0.40%, and the content of SA in S. chinensis compound formula was determined with the help of high-performance liquid chromatography (HPLC), which is a stable and reliable method, and it can lay a foundation for the subsequent quality control. Therefore, this paper systematically reviews the preparation, pharmacological effects, pharmacokinetic properties, and content determination of SA with the goal of updating and deepening the understanding of SA, as well as providing a theoretical basis for the study of SA at a later stage.

2.
Eur J Med Chem ; 271: 116445, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38701715

RESUMO

Lignans are widely distributed in nature, primarily found in the xylem and resins of plants, with the constituent units C6-C3, and their dimers are the most common in plants. In recent years, the trimeric sesquilignans have also received increasing attention from scholars. More than 200 derivatives have been isolated and identified from nearly 50 families, most of which are different types (monoepoxy lignans, bisepoxy lignans, benzofuran lignans) connected with simple phenylpropanoids through ether bonds, C-C bonds, and oxygen-containing rings to constitute sesquilignans. Some of them also possess pharmacological properties, including antioxidants, hepatoprotectives, antitumors, anti-inflammatory properties, and other properties. In addition, the chemical structure of sesquilignans is closely related to the pharmacological activity, and chemical modification of methoxylation enhances the pharmacological activity. In contrast, phenolic hydroxyl and hydroxyl glycosides reduce the pharmacological activity. Therefore, the present review aims to summarize the chemical diversity, bioactivities, and constitutive relationships to provide a theoretical basis for the more profound development and utilization of sesquilignans.


Assuntos
Lignanas , Lignanas/química , Lignanas/farmacologia , Lignanas/isolamento & purificação , Humanos , Antioxidantes/química , Antioxidantes/farmacologia , Estrutura Molecular , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia
3.
Org Lett ; 26(20): 4400-4405, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38735050

RESUMO

An enantioselective Pd-catalyzed intramolecular desymmetrizing cycloisomerization of N-(cyclopent-3-en-1-yl)propiolamides has been developed by employing a new chiral phosphoramidite ligand. A series of structurally unique bridged azabicycles are achieved in moderate to excellent yields with good E/Z selectivity and high enantioselectivity. Synthetic transformations are conducted to demonstrate the practical utility of this reaction.

5.
J Phys Chem Lett ; : 5618-5624, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758202

RESUMO

Iodine-doped bromide perovskite single crystals (IBPSCs) have important applications in optoelectronic fields, such as in solar cells. Currently, much research has aimed to study the phase separation phenomenon and device performance improvements in IBPSCs. However, important intrinsic photoexcited carrier dynamics are often overlooked in IBPSCs. Here, we explored the photoexcited carrier dynamics in typical iodine-doped MAPbBr3 single crystals using the excitation intensity-dependent steady-state photoluminescence (PL) and time-resolved photoluminescence (TRPL) technique. We found that the trap state density changes with an increase in the amount of doped iodine. Further, we noticed that there is an influence of carrier diffusion on the photoexcited carrier dynamics, and then, we evaluated the carrier diffusion coefficients and recombination constants via numerical simulations of the PL kinetics. Consequently, we found that the electron shallow trap-related carrier behaviors substantially impacted the PL kinetics. Our results greatly facilitate a deeper understanding of the fundamental characteristics of mixed halide perovskite material.

6.
EClinicalMedicine ; 72: 102626, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38756107

RESUMO

Background: Previous trials of renal denervation (RDN) have been designed to investigate reduction of blood pressure (BP) as the primary efficacy endpoint using non-selective RDN without intraoperatively verified RDN success. It is an unmet clinical need to map renal nerves, selectively denervate renal sympathetic nerves, provide readouts for the interventionalists and avoid futile RDN. We aimed to examine the safety and efficacy of renal nerve mapping/selective renal denervation (msRDN) in patients with uncontrolled hypertension (HTN) and determine whether antihypertensive drug burden is reduced while office systolic BP (OSBP) is controlled to target level (<140 mmHg). Methods: We conducted a randomized, prospective, multicenter, single-blinded, sham-controlled trial. The study combined two efficacy endpoints at 6 months as primary outcomes: The control rate of patients with OSBP <140 mmHg (non-inferior outcome) and change in the composite index of antihypertensive drugs (Drug Index) in the treatment versus Sham group (superior outcome). This design avoids confounding from excess drug-taking in the Sham group. Antihypertensive drug burden was assessed by a composite index constructed as: Class N (number of classes of antihypertensive drugs) × (sum of doses). 15 hospitals in China participated in the study and 220 patients were enrolled in a 1:1 ratio (msRDN vs Sham). The key inclusion criteria included: age (18-65 years old), history of essential HTN (at least 6 months), heart rate (≥70 bpm), OSBP (≥150 mmHg and ≤180 mmHg), ambulatory BP monitoring (ABPM, 24-h SBP ≥130 mmHg or daytime SBP ≥135 mmHg or nighttime SBP ≥120 mmHg), renal artery stenosis (<50%) and renal function (eGFR >45 mL/min/1.73 m2). The catheter with both stimulation and ablation functions was inserted in the distal renal main artery. The RDN site (hot spot) was selected if SBP increased (≥5 mmHg) by intra-renal artery (RA) electrical stimulation; an adequate RDN was confirmed by repeated electronic stimulation if no increase in BP otherwise, a 2nd ablation was performed at the same site. At sites where there was decreased SBP (≥5 mmHg, cold spot) or no BP response (neutral spot) to stimulation, no ablation was performed. The mapping, ablation and confirmation procedure was repeated until the entire renal main artery had been tested then either treated or avoided. After msRDN, patients had to follow a predefined, vigorous drug titration regimen in order to achieve target OSBP (<140 mmHg). Drug adherence was monitored by liquid chromatography-tandem mass spectrometry analysis using urine. This study is registered with ClinicalTrials.gov (NCT02761811) and 5-year follow-up is ongoing. Findings: Between July 8, 2016 and February 23, 2022, 611 patients were consented, 220 patients were enrolled in the study who received standardized antihypertensive drug treatments (at least two drugs) for at least 28 days, presented OSBP ≥150 mmHg and ≤180 mmHg and met all inclusion and exclusion criteria. In left RA and right RA, mapped sites were 8.2 (3.0) and 8.0 (2.7), hot/ablated sites were 3.7 (1.4) and 4.0 (1.6), cold spots were 2.4 (2.6) and 2.0 (2.2), neutral spots were 2.0 (2.1) and 2.0 (2.1), respectively. Hot, cold and neutral spots was 48.0%, 27.5% and 24.4% of total mapped sites, respectively. At 6 M, the Control Rate of OSBP was comparable between msRDN and Sham group (95.4% vs 92.8%, p = 0.429), achieved non-inferiority margin -10% (2.69%; 95% CI -4.11%, 9.83%, p < 0.001 for non-inferiority); the change in Drug Index was significantly lower in msRDN group compared to Sham group (4.37 (6.65) vs 7.61 (10.31), p = 0.010) and superior to Sham group (-3.25; 95% CI -5.56, -0.94, p = 0.003), indicating msRDN patients need significantly fewer drugs to control OSBP <140 mmHg. 24-hour ambulatory SBP decreased from 146.8 (13.9) mmHg by 10.8 (14.1) mmHg, and from 149.8 (12.8) mmHg by 10.0 (14.0) mmHg in msRDN and Sham groups, respectively (p < 0.001 from Baseline; p > 0.05 between groups). Safety profiles were comparable between msRDN and Sham groups, demonstrating the safety and efficacy of renal mapping/selective RDN to treat uncontrolled HTN. Interpretation: The msRDN therapy achieved the goals of reducing the drug burden of HTN patients and controlling OSBP <140 mmHg, with only approximately four targeted ablations per renal main artery, much lower than in previous trials. Funding: SyMap Medical (Suzhou), LTD, Suzhou, China.

7.
Small Methods ; : e2400015, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607951

RESUMO

Nowadays, the extensively used lead sulfide (PbS) quantum dot (QD) hole transport layer (HTL) relies on layer-by-layer method to replace long chain oleic acid (OA) ligands with short 1,2-ethanedithiol (EDT) ligands for preparation. However, the inevitable significant volume shrinkage caused by this traditional method will result in undesired cracks and disordered QD arrangement in the film, along with adverse increased defect density and inhomogeneous energy landscape. To solve the problem, a novel method for EDT passivated PbS QD (PbS-EDT) HTL preparation using small-sized benzoic acid (BA) as intermediate ligands is proposed in this work. BA is substituted for OA ligands in solution followed by ligand exchange with EDT layer by layer. With the new method, smoother PbS-EDT films with more ordered and closer QD packing are gained. It is demonstrated stronger coupling between QDs and reduced defects in the QD HTL owing to the intermediate BA ligand exchange. As a result, the suppressed nonradiative recombination and enhanced carrier mobility are achieved, contributing to ≈20% growth in short circuit current density (Jsc) and a 23.4% higher power conversion efficiency (PCE) of 13.2%. This work provides a general framework for layer-by-layer QD film manufacturing optimization.

8.
Int J Cardiol ; 407: 132065, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38642720

RESUMO

BACKGROUND: Accurate assessment and timely intervention play a crucial role in ameliorating poor short-term prognosis of acute pulmonary embolism (APE) patients. The currently employed scoring models exhibit a degree of complexity, and some models may not comprehensively incorporate relevant indicators, thereby imposing limitations on the evaluative efficacy. Our study aimed to construct and externally validate a nomogram that predicts 30-day all-cause mortality risk in APE patients. METHODS: Clinical data from APE patients in Intensive Care-IV database was included as a training cohort. Additionally, we utilized our hospital's APE database as an external validation cohort. The nomogram was developed, and its predictive ability was evaluated using receiver operating characteristic (ROC) curves, calibration plots and decision curve analysis. RESULTS: A collective of 1332 patients and 336 patients were respectively enrolled as the training cohort and the validation cohort in this study. Five variables including age, malignancy, oxygen saturation, blood glucose, and the use of vasopressor, were identified based on the results of the multivariate Cox regression model. The ROC value for the nomogram in the training cohort yielded 0.765, whereas in the validation group, it reached 0.907. Notably, these values surpassed the corresponding ROC values for the Pulmonary Embolism Severity Index, which were 0.713 in the training cohort and 0.754 in the validation cohort. CONCLUSIONS: The nomogram including five indicators had a good performance in predicting short-term prognosis in patients with APE, which was easier to apply and provided better recommendations for clinical decision-making.


Assuntos
Nomogramas , Embolia Pulmonar , Humanos , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/mortalidade , Masculino , Feminino , Prognóstico , Pessoa de Meia-Idade , Idoso , Doença Aguda , Valor Preditivo dos Testes , Estudos de Coortes , Estudos Retrospectivos , Fatores de Tempo
9.
J Org Chem ; 89(7): 4979-4989, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38536713

RESUMO

Two efficient and convenient methods for the synthesis of 3-alkylideneoxindoles are described in this paper. The InCl3/TfOH-mediated tandem Knoevenagel condensation-deacylation sequence of various 2-oxindoles with 1,3-diones or acetoacetate furnished 3-alkylideneoxindoles in satisfactory to excellent yields (up to >99% yield). Employing the reaction system, the condensation of 2-oxindoles with ketones or aldehydes also proceeded smoothly to produce 3-alkylideneoxindoles. This protocol can be amenable to scale up. The effect of acids on this condensation reaction and intermolecular competition experiments were investigated to understand the aspect of the reaction.

10.
J Neurosci ; 44(15)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38429106

RESUMO

Adenosinergic modulation in the PFC is recognized for its involvement in various behavioral aspects including sleep homoeostasis, decision-making, spatial working memory and anxiety. While the principal cells of layer 6 (L6) exhibit a significant morphological diversity, the detailed cell-specific regulatory mechanisms of adenosine in L6 remain unexplored. Here, we quantitatively analyzed the morphological and electrophysiological parameters of L6 neurons in the rat medial prefrontal cortex (mPFC) using whole-cell recordings combined with morphological reconstructions. We were able to identify two different morphological categories of excitatory neurons in the mPFC of both juvenile and young adult rats with both sexes. These categories were characterized by a leading dendrite that was oriented either upright (toward the pial surface) or inverted (toward the white matter). These two excitatory neuron subtypes exhibited different electrophysiological and synaptic properties. Adenosine at a concentration of 30 µM indiscriminately suppressed connections with either an upright or an inverted presynaptic excitatory neuron. However, using lower concentrations of adenosine (10 µM) revealed that synapses originating from L6 upright neurons have a higher sensitivity to adenosine-induced inhibition of synaptic release. Adenosine receptor activation causes a reduction in the probability of presynaptic neurotransmitter release that could be abolished by specifically blocking A1 adenosine receptors (A1ARs) using 8-cyclopentyltheophylline (CPT). Our results demonstrate a differential expression level of A1ARs at presynaptic sites of two functionally and morphologically distinct subpopulations of L6 principal neurons, suggesting the intricate functional role of adenosine in neuronal signaling in the brain.


Assuntos
Neurônios , Células Piramidais , Feminino , Masculino , Ratos , Animais , Células Piramidais/fisiologia , Neurônios/fisiologia , Sinapses/fisiologia , Córtex Pré-Frontal/fisiologia , Adenosina/farmacologia , Adenosina/fisiologia
11.
Int J Biol Macromol ; 266(Pt 1): 131121, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522692

RESUMO

In our aging society, dysphagia and malnutrition are growing concerns, necessitating intervention. Liquid nutrition support offers a practical solution for traditional dietary issues, but it raises a key issue: the potential for post-meal glucose spikes impacting efficacy. This study examined the effects of supplementation of Polygonatum cyrtonema Hua polysaccharide (PCP), konjac glucomannan (KGM) and their combination on acute phase postprandial glycemic response and long-term glucose metabolism in T2DM mice on a complete nutritional liquid diet. KGM was more effective in reducing postprandial glucose response, while PCP was more prominent in ameliorating long-term glucose metabolism. The KGM-PCP combination demonstrated superior outcomes in fasting blood glucose, insulin, and glucose homeostasis. PCP and KGM also influenced the composition and abundance of the gut microbiome, with the H-PCP group showing optimal performance. Moreover, the KGM-PCP combination improved body weight, lipid homeostasis, and liver health the most. PCP potentially regulates glycemia through metabolic pathways, while KGM improves glycemic metabolism by reducing postprandial glucose levels in response to viscous intestinal contents. This research identifies the structure, viscosity properties, and hypoglycemic effects of KGM and PCP in complete nutritional liquid diet fed T2DM mice, enabling their strategic utilization as hypoglycemic components in nutritional administration and glycemic regulation.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Mananas , Polygonatum , Polissacarídeos , Animais , Mananas/farmacologia , Mananas/química , Camundongos , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/administração & dosagem , Glicemia/metabolismo , Polygonatum/química , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Masculino , Microbioma Gastrointestinal/efeitos dos fármacos , Insulina/sangue , Insulina/metabolismo , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/dietoterapia
12.
Molecules ; 29(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38542912

RESUMO

During the development of a sand-conglomerate reservoir, there is a huge variation in rock grain size and different åmineral compositions of different-sized sand grains. The mineral composition and microstructure of the rock both have an impact on the characteristics of the remaining oil in the reservoir. The stripping mechanism of a surfactant system on sand-conglomerate surface crude oil with varied grain size minerals was explored in this paper. Sand-conglomerate was classified and analyzed to determine their wettability and stripping oil effects. The optimization of the surfactant solution system and molecular dynamics simulation revealed the surfactant stripping mechanism on crude oil on distinct sandstone minerals. The results of the study showed that montmorillonite minerals are more readily adsorbed by surfactants. The crude oil within them is more likely to compete for adsorption and to be stripped off, and then extracted with the recovery fluid. The surfactant solution system can increase the hydrophilicity of the rock surface, make the crude oil on the rock surface shrink and gather, and enhance the transportation ability of the displacement fluid. And the emulsification seals part of the pore in the reservoir, increases the displacement pressure, and improves the overall wave volume. The results of this paper are of great significance for the efficient development of sand-conglomerate reservoirs.

13.
World J Gastrointest Oncol ; 16(2): 343-353, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38425394

RESUMO

BACKGROUND: The controlling nutritional status (CONUT) score effectively reflects a patient's nutritional status, which is closely related to cancer prognosis. This study investigated the relationship between the CONUT score and prognosis after radical surgery for colorectal cancer, and compared the predictive ability of the CONUT score with other indexes. AIM: To analyze the predictive performance of the CONUT score for the survival rate of colorectal cancer patients who underwent potentially curative resection. METHODS: This retrospective analysis included 217 patients with newly diagnosed colorectal. The CONUT score was calculated based on the serum albumin level, total lymphocyte count, and total cholesterol level. The cutoff value of the CONUT score for predicting prognosis was 4 according to the Youden Index by the receiver operating characteristic curve. The associations between the CONUT score and the prognosis were performed using Kaplan-Meier curves and Cox regression analysis. RESULTS: Using the cutoff value of the CONUT score, patients were stratified into CONUT low (n = 189) and CONUT high groups (n = 28). The CONUT high group had worse overall survival (OS) (P = 0.013) and relapse-free survival (RFS) (P = 0.015). The predictive performance of CONUT was superior to the modified Glasgow prognostic score, the prognostic nutritional index, and the neutrophil-to-lymphocyte ratio. Meanwhile, the predictive performances of CONUT + tumor node metastasis (TNM) stage for 3-year OS [area under the receiver operating characteristics curve (AUC) = 0.803] and 3-year RFS (AUC = 0.752) were no less than skeletal muscle mass index (SMI) + TNM stage. The CONUT score was negatively correlated with SMI (P < 0.01). CONCLUSION: As a nutritional indicator, the CONUT score could predict long-term outcomes after radical surgery for colorectal cancer, and its predictive ability was superior to other indexes. The correlation between the CONUT score and skeletal muscle may be one of the factors that play a predictive role.

14.
Nanomaterials (Basel) ; 14(4)2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38392749

RESUMO

Cs2NaInCl6 double perovskites, which have excellent photoelectric conversion properties and are non-toxic and lead-free, have recently gained significant attention. In particular, double-perovskite quantum dots (QDs) are viewed as a promising material for optoelectronic device applications. Ligands such as oleic acid (OA) and oleylamine (OAm) are essential for the synthesis of perovskite QDs, but their specific roles in double-perovskite QDs remain unclear. In this study, we have investigated the binding of OA and OAm to Cs2NaInCl6 QDs through FTIR and NMR and their effects on the surface defect reduction and stability improvement for Cs2NaInCl6 QDs. We found that only OAm was bound to the QD surfaces while OA was not. The OAm has a significant effect on the photoluminescence quantum yield (PLQY) improvement by passivating the QD surface defects. The stability of the QDs was also evaluated, and it was observed that OA played a significant role in the stability of the QDs. Our findings provide valuable insights into the roles of ligands in influencing the photophysical properties and stability of lead-free double-perovskite QDs.

15.
Heliyon ; 10(4): e26178, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404876

RESUMO

Introduction: Chylothorax is caused by lymphatic chyle fluid leaking back through the thoracic duct and accumulating in the pleural cavity. It is related to a thoracic duct injury or occlusion. It is rare to have bilateral chylothorax after cervical lymph node dissection for thyroid cancer diagnosis. Case report: A 28-year-old woman was admitted to our hospital with bilateral hypoechoic thyroid nodules and cervical lymph node abnormalities. She underwent thyroidectomy and lymphadenectomy but developed chylothorax 3 days after surgery. She was treated with bilateral thoracic drainage, electrolyte supplementation, and somatostatin, and was discharged 17 days post-treatment. Conclusion: Bilateral chylothorax is a rare complication of thyroid cancer surgery. Early diagnosis and treatment, especially the detection of dyspnea, are key. Also, unobstructed bilateral thoracic drainage, improved surgical skills, and reduced thoracic duct injuries can help reduce complications.

16.
Oncol Lett ; 27(3): 133, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38362234

RESUMO

For patients with gastrointestinal stromal tumors (GISTs) and liver metastases, there is still debate about whether radiofrequency ablation (RFA) or hepatectomy is preferable. The present study aimed to compare the clinical outcomes of RFA with hepatectomy in patients with GISTs and liver metastases. The present retrospective study consisted of a cohort of 43 patients who had been diagnosed with liver metastases from GISTs between January 2010 and December 2022. The study included 18 patients who received RFA combined with tyrosine kinase inhibitor (TKI) therapy (RFA group) and 25 patients who underwent hepatectomy combined with TKI therapy (hepatectomy group). For the patients with liver metastases, the progression-free survival (PFS) rates at 1, 3 and 5 years were 66.5, 38.2 and 33.9%, respectively. Notably, patients in the hepatectomy group exhibited significantly improved PFS times compared with those in the RFA group (median PFS, 42.7 months vs. 14.3 months; P=0.034). Furthermore, the time to imatinib treatment failure (TTF) was notably improved in the hepatectomy group compared with that in the RFA group, and this difference was statistically significant (median TTF, 71.1 vs. 38.0 months; P=0.041). However, the overall survival (OS) times of patients who received RFA and those who had hepatectomy did not differ significantly (median OS, not reached vs. not reached, P=0.120). There was no statistically significant distinction in PFS and TTF between patients who underwent hepatectomy combined with postoperative TKI and those who underwent hepatectomy combined with perioperative TKI (median PFS, 29.5 vs. not reached; P=0.520; median TTF, 66.4 months vs. 71.1 months; P=0.430). The univariate and multivariate analyses consistently identified the sole prognostic factor affecting PFS as hepatectomy combined with TKI therapy (hazard ratio, 0.379; 95% CI, 0.159-0.899; P=0.028). In conclusion, hepatectomy combined with TKI therapy improved prognosis for patients with liver metastases to a greater extent than RFA combined with TKI therapy. For this type of patient, hepatectomy may be a preferable option.

17.
Microbiol Res ; 281: 127599, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38219635

RESUMO

The colonic mucus layer plays a critical role in maintaining the integrity of the colonic mucosal barrier, serving as the primary defense against colonic microorganisms. Predominantly composed of mucin 2 (MUC2), a glycosylation-rich protein, the mucus layer forms a gel-like coating that covers the colonic epithelium surface. This layer provides a habitat for intestinal microorganisms, which can utilize mucin glycans present in the mucus layer as a sustainable source of nutrients. Additionally, metabolites produced by the microbiota during the metabolism of mucus glycans have a profound impact on host health. Under normal conditions, the production and consumption of mucus maintain a dynamic balance. However, several studies have demonstrated that certain factors, such as dietary fiber deficiency, can enhance the metabolism of mucus glycans by gut bacteria, thereby disturbing this balance and weakening the mucus barrier function of the mucus layer. To better understand the occurrence and development of colon-related diseases, it is crucial to investigate the complex metabolic patterns of mucus glycosylation by intestinal microorganisms. Our objective was to comprehensively review these patterns in order to clarify the effects of mucus layer glycan metabolism by intestinal microorganisms on the host.


Assuntos
Formigas , Mucosa Intestinal , Animais , Mucosa Intestinal/metabolismo , Muco/metabolismo , Mucina-2/metabolismo , Mucinas/metabolismo , Colo/metabolismo , Colo/microbiologia , Polissacarídeos/metabolismo , Formigas/metabolismo
18.
J Am Chem Soc ; 146(5): 3094-3101, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38269444

RESUMO

Inorganic tin (Sn) perovskite nanocrystals offer a promising solution to the potential toxicity concerns associated with their established lead (Pb)-based counterparts. Yet, achieving their superior stability and optoelectronic properties remains an ongoing challenge. Here, we report a synthesis of high-symmetry α-phase CsSnI3 nanocrystals with an ultralong 278 ns carrier lifetime, exceeding previous benchmarks by 2 orders of magnitude through meticulous Sn(IV) control. The nanocrystals demonstrate excellent colloidal stability, uniform monodispersity, and a distinct exciton peak. Central to these outcomes is our designed solid-liquid antioxidation suspension of tri-n-octylphosphine (TOP) and zerovalent tin (Sn(0)) that fully addresses the unique coexisting oxygen-driven and solvent-driven Sn oxidation mechanisms in Sn perovskite nanocrystal synthesis. We uncover the largely undervalued function of TOP in mitigating oxygen-driven Sn oxidation and introduce Sn(0) powder to generate a synergistic antioxidation function with TOP, significantly reducing Sn(IV)-induced defects and distortions and contributing to enhanced optoelectronic properties. Strikingly, this approach also profoundly impacts inorganic Sn-Pb perovskite nanocrystals, boosting lifetimes by 2 orders of magnitude and increasing photoluminescence quantum yield over 100-fold to 35%. Our findings illuminate the potential of Sn-based nanocrystals for optoelectronic applications.

19.
Theranostics ; 14(1): 283-303, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38164152

RESUMO

Rationale: Intracerebral hemorrhage (ICH) is a devastating cerebrovascular disease resulting from blood extravasating into the brain parenchyma. Escalation of erythrophagocytosis (a form of efferocytosis), avoiding the consequent release of the detrimental erythrocyte lysates, may be a promising target of ICH management. The ADAM17 inhibitor and liver X receptor (LXR) agonist could promote efficient efferocytosis and injury repair. Nevertheless, the poor bioavailability and restriction of the blood-brain barrier (BBB) hinder their application. Therefore, it is needed that biocompatible and smart nanoplatforms were designed and synthesized to realize effective therapy targeting erythrophagocytosis. Methods: We first assessed the synergistic effect of therapeutic GW280264X (an ADAM17 inhibitor) and desmosterol (an LXR agonist) on erythrophagocytosis in vitro. Then a pH-responsive neutrophil membrane-based nanoplatform (NPEOz) served as a carrier to accurately deliver therapeutic GW280264X and desmosterol to the damaged brain was prepared via co-extrusion. Afterwards, their pH-responsive performance was valued in vitro and targeting ability was assessed through fluorescence image in vivo. Finally, the pro-erythrophagocytic and anti-neuroinflammatory ability of the nanomedicine and related mechanisms were investigated. Results: After the synergistical effect of the above two drugs on erythrophagocytosis was confirmed, we successfully developed neutrophil-disguised pH-responsive nanoparticles to efficiently co-deliver them. The nanoparticles could responsively release therapeutic agents under acidic environments, and elicit favorable biocompatibility and ability of targeting injury sites. D&G@NPEOz nanoparticles enhanced erythrophagocytosis through inhibiting shedding of the efferocytotic receptors MERTK/AXL mediated by ADAM17 and accelerating ABCA-1/ABCG-1-mediated cholesterol efflux regulated by LXR respectively. In addition, the nano-formulation was able to modulate the inflammatory microenvironment by transforming efferocytes towards a therapeutic phenotype with reducing the release of proinflammatory cytokines while increasing the secretion of anti-inflammatory factors, and improve neurological function. Conclusions: This biomimetic nanomedicine is envisaged to offer an encouraging strategy to effectively promote hematoma and inflammation resolution, consequently alleviate ICH progression.


Assuntos
Nanopartículas , Neutrófilos , Camundongos , Animais , Humanos , Desmosterol , Camundongos Endogâmicos C57BL , Hemorragia Cerebral/tratamento farmacológico , Receptores X do Fígado , Concentração de Íons de Hidrogênio
20.
Food Chem ; 442: 138505, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38266408

RESUMO

Streptomycin (STR), an aminoglycoside antibiotic with the potential to persist in honey and other food products, may induce allergy, toxicity and antibiotic resistance in humans. In this study, we developed a solid-phase microextraction (SPME) biosensor based on a quartz rod that was modified with double-stranded DNA structures consisting of partially complementary G-rich base DNA strand and STR aptamer. The STR isolated by SPME initially bound to the aptamer. Then the remaining double-stranded DNA structures were cleaved by the Nt.BstNBI enzyme, resulting in release of G-quadruplex dimers. The latter formed a complex with thioflain T fluorescent dye, resulting in an amplified fluorescence response. The method exhibited high sensitivity (a limit of detection of 10.84 pM), wide linear range (0.05 nM âˆ¼ 500 nM (with determination coefficient > 0.99)), and simple operation, making it suitable and convenient for STR detection. Successful STR determination in genuine honey samples was demonstrated.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Mel , Humanos , Estreptomicina , Mel/análise , Microextração em Fase Sólida/métodos , DNA , Aptâmeros de Nucleotídeos/química , DNA Complementar , Técnicas Biossensoriais/métodos , Limite de Detecção
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