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1.
Cell Biosci ; 14(1): 126, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39354565

ABSTRACT

BACKGROUND: Occludin, a crucial component of tight junctions, has emerged as a promising biomarker for the diagnosis of acute ischemic disease, highlighting its significant potential in clinical applications. In the diabetes, Occludin serves as a downstream target gene intricately regulated by the adiponectin (APN) signaling pathway. However, the specific mechanism by which adiponectin regulates Occludin expression remains unclear. METHODS AND RESULTS: Endothelial-specific Ocln knockdown reduced APN-mediated blood flow recovery after femoral artery ligation and nullified APN's protection against high-fat diet (HFD)-triggered apoptosis and angiogenesis inhibition in vivo. Mechanically, we have meticulously elucidated APN's regulatory role in Occludin expression through a comprehensive analysis spanning transcriptional and post-translational dimensions. Foxo1 has been elucidated as a crucial transcriptional regulator of Occludin that is modulated by the APN/APPL1 signaling axis, as evidenced by validation through ChIP-qPCR assays and Western blot analysis. APN hindered Occludin degradation via the ubiquitin-proteasome pathway. Mass spectrometry analysis has recently uncovered a novel phosphorylation site, Tyr467, on Occludin. This site responds to APN, playing a crucial role in inhibiting Occludin ubiquitination by APN. The anti-apoptotic and pro-angiogenic effects of APN were attenuated in vitro and in vivo following Foxo1 knockdown or expression of a non-phosphorylatable mutant, OccludinY467A. Clinically, elevated plasma concentrations of Occludin were observed in patients with diabetes. A significant negative correlation was found between Occludin levels and APN concentrations. CONCLUSION: Our study proposes that APN modulates Occludin expression through mechanisms involving both transcriptional and post-translational interactions, thereby conferring a protective effect on endothelial integrity within diabetic vasculature.

2.
Am J Chin Med ; : 1-32, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39347953

ABSTRACT

Phytochemical flavonoids have been proven to be effective in treating various disorders, including cardiovascular diseases. Acacetin is a natural flavone with diverse pharmacological effects, uniquely including atrial-selective anti-atrial fibrillation (AF) via the inhibition of the atrial specific potassium channel currents [Formula: see text] (ultra-rapidly delayed rectifier potassium current), [Formula: see text] (acetylcholine-activated potassium current), [Formula: see text] (calcium-activated small conductance potassium current), and [Formula: see text] (transient outward potassium current). [Formula: see text] inhibition by acacetin, notably, suppresses experimental J-wave syndromes. In addition, acacetin provides extensive cardiovascular protection against ischemia/reperfusion injury, cardiomyopathies/heart failure, autoimmune myocarditis, pulmonary artery hypertension, vascular remodeling, and atherosclerosis by restoring the downregulated intracellular signaling pathway of Sirt1/AMPK/PGC-1[Formula: see text] followed by increasing Nrf2/HO-1/SOD thereby inhibiting oxidation, inflammation, and apoptosis. This review provides an integrated insight into the capabilities of acacetin as a drug candidate for treating cardiovascular diseases, especially atrial fibrillation and cardiomyopathies/heart failure.

3.
Quant Imaging Med Surg ; 14(9): 6337-6351, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39281181

ABSTRACT

Background: Accurately distinguishing between Parkinson disease (PD) and healthy controls (HCs) through reliable imaging method is crucial for appropriate therapeutic intervention. However, PD diagnosis is hindered by the subjective nature of the evaluation. We aimed to develop an automatic deep-learning method that can segment the substantia nigra areas on susceptibility-weighted imaging (SWI) and T2-weighted imaging (T2WI) and further differentiate patients with PD from HCs using a machine learning algorithm. Methods: Magnetic resonance imaging (MRI) data from 83 patients with PD and 83 age- and sex-matched HCs were obtained on the same 3.0-T MRI scanner. A deep learning method with Swin-Unet was developed to segment volumes of interest (VOIs) on SWI and then map the VOIs on SWI to the corresponding T2WI; features were then extracted from the VOIs on SWI and T2WI. Three machine learning models were developed and compared to differentiate those with PD from HCs. Results: Swin-Unet achieved a better Dice coefficient than did U-Net in SWI segmentation (0.832 vs. 0.712). Machine learning models outperformed visual analysis (P>0.05), and logistic regression (LR) achieved the best performance [area under the curve (AUC) ≥0.819] and the most stable (relative standard deviations in AUC ≤0.05). The test results showed that the AUC of the LR model based on SWI segmentation was 0.894 while that of the LR model based on T2WI segmentation was 0.876. There was no significant difference in VOIs based on manual labeling or automatic segmentation across T2WI, SWI, or a combination of the two (P>0.05). The AUCs of the LR model based on automatic segmentation were close to those of the model based on manual labeling (P>0.05). Conclusions: Our approach could provide a powerful and useful method for automatically and rapidly diagnosing PD in the clinic with only T2WI.

4.
Saudi Med J ; 45(9): 900-910, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39218457

ABSTRACT

OBJECTIVES: To evaluate the outcomes of adjuvant radiotherapy in patients with esophageal cancer (EC) who underwent esophagectomy following neoadjuvant chemoradiotherapy (NCRT). METHODS: The data of EC patients who received adjuvant therapy after NCRT between 2004 to 2019 was retrieved from the SEER database. The patients were split into the adjuvant radiotherapy with or without chemotherapy (RT±CT) and the adjuvant chemotherapy (CT) groups. The process of propensity score matching (PSM) was employed. RESULTS: Following PSM, 157 patients in total were recruited in each treatment group. There were no significant variations in either overall survival (OS) or cancer-specific survival (CSS) between the RT±CT and CT groups (median OS: 28 months versus. 51 months, p=0.063; median CSS: 31 months versus. 52 months, p=0.16). Within the CT group, patients with ypI/II or cI/II tumor stage, positive lymph node ratio (LNR) ≤0.1, and tumor size ≥50 mm (p<0.05) had higher OS compared to the RT±CT groups. Among patients with cT3-4 tumors in N-stage downstaging group, the OS and CSS were significantly greater for those underwent RT±CT as opposed to the CT group (5-year OS:56.6% versus 19.4%, p=0.042; 5-year CSS:67.9% versus. 19.4%, p=0.023). Multivariate Cox regression analysis identified the tumor histology grade as an independent prognostic factor of OS and CSS. CONCLUSION: Radiotherapy-based adjuvant therapy does not significantly improve the prognosis of EC patients after NCRT, although it may provide a survival benefit for patients with cT3-4 tumors in N-stage downstaging.


Subject(s)
Esophageal Neoplasms , Esophagectomy , Neoadjuvant Therapy , SEER Program , Humans , Esophageal Neoplasms/therapy , Esophageal Neoplasms/pathology , Esophageal Neoplasms/mortality , Male , Female , Middle Aged , Radiotherapy, Adjuvant , Aged , Neoplasm Staging , Chemoradiotherapy, Adjuvant , Propensity Score , Survival Rate , Chemotherapy, Adjuvant
5.
Risk Manag Healthc Policy ; 17: 1959-1972, 2024.
Article in English | MEDLINE | ID: mdl-39156077

ABSTRACT

Purpose: This study aimed to develop an integrative dynamic nomogram, including N-terminal pro-B type natural peptide (NT-proBNP) and estimated glomerular filtration rate (eGFR), for predicting the risk of all-cause mortality in HFmrEF patients. Patients and Methods: 790 HFmrEF patients were prospectively enrolled in the development cohort for the model. The least absolute shrinkage and selection operator (LASSO) regression and Random Survival Forest (RSF) were employed to select predictors for all-cause mortality. Develop a nomogram based on the Cox proportional hazard model for predicting long-term mortality (1-, 3-, and 5-year) in HFmrEF. Internal validation was conducted using Bootstrap, and the final model was validated in an external cohort of 338 consecutive adult patients. Discrimination and predictive performance were evaluated by calculating the time-dependent concordance index (C-index), area under the ROC curve (AUC), and calibration curve, with clinical value assessed via decision curve analysis (DCA). Integrated discrimination improvement (IDI) and net reclassification improvement (NRI) were used to assess the contributions of NT-proBNP and eGFR to the nomogram. Finally, develop a dynamic nomogram using the "Dynnom" package. Results: The optimal independent predictors for all-cause mortality (APSELNH: A: angiotensin-converting enzyme inhibitors/angiotensin receptor blockers/angiotensin receptor-neprilysin inhibitor (ACEI/ARB/ARNI), P: percutaneous coronary intervention/coronary artery bypass graft (PCI/CABG), S: stroke, E: eGFR, L: lg of NT-proBNP, N: NYHA, H: healthcare) were incorporated into the dynamic nomogram. The C-index in the development cohort and validation cohort were 0.858 and 0.826, respectively, with AUCs exceeding 0.8, indicating good discrimination and predictive ability. DCA curves and calibration curves demonstrated clinical applicability and good consistency of the nomogram. NT-proBNP and eGFR provided significant net benefits to the nomogram. Conclusion: In this study, the dynamic APSELNH nomogram developed serves as an accessible, functional, and effective clinical decision support calculator, offering accurate prognostic assessment for patients with HFmrEF.

6.
Front Immunol ; 15: 1425443, 2024.
Article in English | MEDLINE | ID: mdl-39104538

ABSTRACT

T cells, as a major lymphocyte population involved in the adaptive immune response, play an important immunomodulatory role in the early stages of autoimmune diseases. Autophagy is a cellular catabolism mediated by lysosomes. Autophagy maintains cell homeostasis by recycling degraded cytoplasmic components and damaged organelles. Autophagy has a protective effect on cells and plays an important role in regulating T cell development, activation, proliferation and differentiation. Autophagy mediates the participation of T cells in the acquired immune response and plays a key role in antigen processing as well as in the maintenance of T cell homeostasis. In autoimmune diseases, dysregulated autophagy of T cells largely influences the pathological changes. Therefore, it is of great significance to study how T cells play a role in the immune mechanism of autoimmune diseases through autophagy pathway to guide the clinical treatment of diseases.


Subject(s)
Autoimmune Diseases , Autophagy , T-Lymphocytes , Humans , Autophagy/immunology , Autoimmune Diseases/immunology , Animals , T-Lymphocytes/immunology , Lymphocyte Activation/immunology
7.
Molecules ; 29(16)2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39202949

ABSTRACT

Graphitic carbon nitride (g-C3N4), known for being nontoxic, highly stable, and environmentally friendly, is extensively used in photocatalytic degradation technologies. Silver nanoparticles effectively capture the photogenerated electrons in g-C3N4, enhancing the photocatalytic efficiency. This study primarily focused on synthesizing graphitic carbon nitride via thermal polymerization and depositing noble metal silver onto g-C3N4 through photoreduction. Methyl orange (MO) and methylene blue (MB) were targeted as the pollutants in the photocatalytic experiments under visible light in conjunction with a H2O2 system. The characteristics peaks, structure, and morphology were analyzed using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). g-C3N4 loaded with 6% Ag exhibited superior photocatalytic performance; the photocatalytic fraction of the degraded materials of the MO and MB solutions reached 100% within 70 and 80 min, respectively, upon adding 1 mL and 2 mL of H2O2. ·OH and ·O2- were the primary active free radicals in the dye degradation process within the synergistic system. Stability tests also demonstrated that the photocatalyst maintained good reusability under the synergistic system.

8.
BMC Oral Health ; 24(1): 962, 2024 Aug 17.
Article in English | MEDLINE | ID: mdl-39154183

ABSTRACT

BACKGROUND: This study investigated the characteristics of Monson's sphere in Chinese young adult females with individual normal occlusion to provide a reference for oral rehabilitation in prosthodontic and orthodontic treatments. METHODS: Points at the dental cusps and incisal edges were selected from 51 digital mandibular dental models of Chinese young adult females (aged 18-22 years) with individual normal occlusion. Monson's spheres were fitted to the selected points based on the least-squares principle and the radii were calculated. The deviation of each selected point from its relative spherical surface was also calculated. The radii and deviations of these points were examined using conventional descriptive statistics and distributions of the most deviated points inside and outside the spheres were analyzed. RESULTS: The mean radius of Monson's sphere in Chinese young adult females was 79.60 ± 14.13 mm. The deviation of each selected point from its relative sphere surface was 0.38 ± 0.30 mm. The maximum deviations inside and outside the sphere were 0.93 ± 0.25 mm and 0.95 ± 0.30 mm, respectively. The most deviated points outside the spheres were mainly distributed at the distolingual cusps of the mandibular second permanent molars (31.37%), while those inside the spheres were mainly distributed at the mesiolingual cusps of the mandibular first permanent molars (45.10%). CONCLUSIONS: The radius of Monson's sphere in Chinese young adult females was smaller than the classic four-inch value suggested by Monson. Deviation was observed from all selected points to their Monson's sphere surface, with the most deviated points distributed primarily in the molar region.


Subject(s)
Mandible , Models, Dental , Humans , Female , Young Adult , Adolescent , Mandible/anatomy & histology , Dental Occlusion , Imaging, Three-Dimensional/methods , China , East Asian People
9.
Front Vet Sci ; 11: 1418165, 2024.
Article in English | MEDLINE | ID: mdl-38966561

ABSTRACT

To compare the impact of nanoselenium and sodium selenite on the performance, blood indices, and milk metabolites of dairy cows during the peak lactation period, two groups of dairy cows under the same conditions were selected as the control group (CON group) and treatment group (NSe group) for a 38-day (10 days for adaptation and 28 days for sampling) experiment. The control group (CON) was provided a basal diet +3.3 g/d of sodium selenite (purity1%), whereas the nanoselenium group (NSe) was offered the same diet +10 mL/d of nanoselenium (selenium concentration 1,500 mg/L). The results showed that NSe significantly increased the milk yield, milk selenium content, and feed efficiency (p < 0.05), but had no significant effect on other milk components (p > 0.05). NSe significantly increased blood urea nitrogen (BUN) and alkaline phosphatase (ALP) (p < 0.05), but had no significant effects on malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), blood total antioxidant capacity (T-AOC), or blood selenium (p > 0.05). In addition, the nontargeted metabolomics of the milk was determined by LC-MS technology, and the differentially abundant metabolites and their enrichment pathways were screened. According to these findings, NSe considerably increased the contents of cetylmannoside, undecylenoic acid, 3-hydroxypentadecanoic acid, 16-hydroxypentadecanoic acid, threonic acid, etc., but decreased the contents of galactaric acid, mesaconic acid, CDP-glucose etc. Furthermore, the enriched metabolic pathways that were screened with an impact value greater than 0.1 included metabolism of niacin and niacinamide, pyruvate, citrate cycle, riboflavin, glycerophospholipid, butanoate and tyrosine. Pearson correlation analysis also revealed a relationship between different milk metabolites and blood selenium, as well as between milk selenium and blood biochemical indices. In conclusion, compared with sodium selenite, nanoselenium improves the milk yield, feed efficiency, and milk selenium content of dairy cows and regulates milk metabolites and related metabolic pathways in Holstein dairy cows during the peak lactation period, which has certain application prospects in dairy production.

10.
World J Gastrointest Oncol ; 16(6): 2380-2393, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38994149

ABSTRACT

Hepatic artery infusion chemotherapy (HAIC) has good clinical efficacy in the treatment of advanced hepatocellular carcinoma (HCC); however, its efficacy varies. This review summarized the ability of various markers to predict the efficacy of HAIC and provided a reference for clinical applications. As of October 25, 2023, 51 articles have been retrieved based on keyword predictions and HAIC. Sixteen eligible articles were selected for inclusion in this study. Comprehensive literature analysis found that methods used to predict the efficacy of HAIC include serological testing, gene testing, and imaging testing. The above indicators and their combined forms showed excellent predictive effects in retrospective studies. This review summarized the strategies currently used to predict the efficacy of HAIC in middle and advanced HCC, analyzed each marker's ability to predict HAIC efficacy, and provided a reference for the clinical application of the prediction system.

11.
Food Res Int ; 191: 114699, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39059955

ABSTRACT

Ascorbic acid (AsA) is an indicator of the nutritional value of freshly cut kiwifruit during storage at 4℃, and its degradation can be inhibited after ozone treatment (1 mg/L, 10 min). The aim of this study was to elucidate the regulatory mechanism affecting AsA metabolism in fresh-cut kiwifruit after ozone treatment. In this study, ozone treatment not only prevented the decrease in AsA/dehydroascorbic acid and delayed the accumulation of total soluble solids/titratable acidity, but also altered phytohormone levels differently. Transcriptomic profiling combined with cis-acting element and correlation analysis were performed to reveal that abscisic acid and salicylic acid synergistically delay AsA degradation under ozone-treatment conditions. Actinidia03760, encoding ascorbate peroxidase, could be specifically recognized by the bZIP transcription factor and is considered a key candidate gene for further research. Collectively, ozone treatment is a promising method for preserving AsA content and improving the nutrition of fresh-cut kiwifruit.


Subject(s)
Actinidia , Ascorbic Acid , Fruit , Gene Expression Profiling , Ozone , Plant Growth Regulators , Signal Transduction , Actinidia/genetics , Actinidia/chemistry , Actinidia/metabolism , Plant Growth Regulators/metabolism , Plant Growth Regulators/pharmacology , Fruit/metabolism , Fruit/chemistry , Fruit/drug effects , Signal Transduction/drug effects , Gene Expression Regulation, Plant/drug effects , Transcriptome , Salicylic Acid , Abscisic Acid/metabolism
12.
Small ; : e2403852, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39046073

ABSTRACT

N-type PbSe thermoelectric materials encounter challenges in improving the power factor due to the single-band structure near the Fermi level, which obstructs typical band convergence. The primary strategy for enhancing the thermoelectric figure of merit (ZT) for n-type PbSe involves reducing lattice thermal conductivity (κlat) by introducing various defect structures. However, lattice mismatches resulting from internal defects within the matrix can diminish carrier mobility, thereby affecting electrical transport properties. In this study, n-type AgCuTe-alloyed PbSe systems achieve a peak ZT value of ≈1.5 at 773 K. Transmission electron microscopy reveals nanoprecipitates of Ag2Te, the room temperature second phase of AgCuTe, within the PbSe matrix. Meanwhile, a unique semi-coherent phase boundary is observed between the PbSe matrix and the Ag2Te nanoprecipitates. This semi-coherent phase interface effectively scatters low-frequency phonons while minimizing damage to carrier mobility. Additionally, the dynamic doping effect of Cu atoms from the decomposition of AgCuTe within the matrix further optimize the high-temperature thermoelectric performance. Overall, these factors significantly enhance the ZT across the whole temperature range. The ZT value of ≈1.5 indicates high competitiveness compared to the latest reported n-type PbSe materials, suggesting that these findings hold promise for advancing the development of efficient thermoelectric systems.

13.
Article in English | MEDLINE | ID: mdl-38978507

ABSTRACT

In hypertrophic scars, the differentiation and migration of fibroblasts are influenced by the extracellular matrix microenvironment, which includes factors such as stiffness, restraint, and tensile force. These mechanical stresses incite alterations in cell behavior, accompanied by cytoskeletal protein reorganization. However, the role of nucleo-skeletal proteins in this context remains underexplored. In this study, we use a polyacrylamide hydrogel (PAA) to simulate the mechanical stress experienced by cells in scar tissue and investigate the impact of Emerin on cell behavior. We utilize atomic force microscopy (AFM) and RNA interference technology to analyze cell differentiation, migration, and stiffness. Our findings reveal that rigid substrates and cellular restriction elevate Emerin expression and diminish differentiation. Conversely, reducing Emerin expression leads to attenuated cell differentiation, where stiffness and constraining factors exert no notable influence. Furthermore, a softening of cells and an enhanced migration rate are also markedly observed. These observations indicate that variations in nuclear skeletal proteins, prompted by diverse matrix microenvironments, play a pivotal role in the pathogenesis of hypertrophic scars (HSs). This research offers novel insights and a reference point for understanding scar fibrosis formation mechanisms and preventing fibrosis.

14.
Discov Oncol ; 15(1): 252, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38954151

ABSTRACT

OBJECTIVE: To evaluate the diagnostic value of 68Ga-prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) for intracapsular prostate cancer with a poor prognosis (PPC) and no extracapsular invasion or distant metastasis. METHODS: The PET/CT images and clinical data of 221 patients were retrospectively analyzed. These patients all had clear pathological results. The maximum standard uptake value (SUVmax) of the main lesions was measured at the postprocessing workstation and was tested for correlation with the pathological score. The diagnostic accuracy was calculated using the receiver operating characteristic (ROC) curve, and the best diagnostic threshold was calculated. The correlation between SUVmax and the International Society of Urological Pathology Grade Group (GG) was also analyzed. RESULTS: The pathological results of the 221 patients were 48 benign lesions and 173 malignant lesions, including 81 PPC. Low-, intermediate-, and high-risk prostate cancers made up 21.97% (38/173), 54.33% (94/173), and 23.70% (41/173) of the malignant lesions, respectively. SUVmax and GG were positively correlated (r = 0.54, P < 0.01). The best SUVmax thresholds for 68Ga-PSMA PET/CT for the diagnosis of intracapsular PC and PPC were 7.95 and 13.94, respectively; the specificities were 0.83 and 0.85, the negative predictive values were 0.55 and 0.87, and the areas under the ROC curves were 0.88 and 0.88, respectively. CONCLUSION: 68Ga-PSMA PET/CT has high specificity and NPV in the diagnosis of intracapsular PPC, but the sensitivity for the diagnosis of intracapsular low-risk PC is low, which may cause some cases to be undetected.

15.
Antioxidants (Basel) ; 13(6)2024 May 27.
Article in English | MEDLINE | ID: mdl-38929089

ABSTRACT

Oxidative stress damage in periparturient cows decreases both production and their health; supplementation with complex additives during the periparturient period has been used as an important strategy to enhance the antioxidant status and production of dairy cows. The periparturient cows not only risk a negative energy balance due to reduced dry matter intake but also represent a sensitive period for oxidative stress. Therefore, we have developed an immunomodulatory and nutritional regulation combined additive (INC) that hopefully can improve the immune status and production of cows during the periparturient period and their offspring health and growth by improving their antioxidant stress status. The INC comprised a diverse array of additives, including water-soluble and fat-soluble vitamins, Selenomethionine, and active dry Saccharomyces cerevisiae. Forty-five multiparous Holstein cows were randomly assigned to three treatments: CON (no INC supplementation, n = 15), INC30 (30 g/d INC supplementation, n = 15), and INC60 (60 g/d INC supplementation, n = 15) based on last lactation milk yield, body condition score, and parity. Newborn calves were administered 4 L of maternal colostrum originating from the corresponding treatment and categorized based on the treatment received by their respective dams. The INC not only served to maintain the antioxidative stress system of dairy cows during the periparturient period but also showed a tendency to improve the immune response (lower tumor necrosis factor and interleukin-6) during the perinatal period. A linear decrease in concentrations of alkaline phosphatase postpartum and ß-hydroxybutyrate was observed with INC supplementation. Milk fat yield, milk protein yield, and energy-corrected milk yield were also increased linearly with increasing additive supplementation. Calves in the INC30 group exhibited greater wither height and chest girth but no significant effect on average daily gain or body weight. The diarrhea frequency was linearly decreased with the incremental level of INC. Results indicate that supplementation with INC in peripartum dairy cows could be a major strategy to improve immune response, decrease inflammation, maintain antioxidant stress status in transition dairy cows, and have merit in their calves. In conclusion, this study underlines the benefits of INC supplementation during the transition period, as it improved anti-inflammatory capacity, could positively impact antioxidative stress capacity, and eventually enhanced the production performance of dairy cows and the health and growth of calves.

16.
Opt Express ; 32(9): 15065-15077, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38859166

ABSTRACT

Optical resonators made of 2D photonic crystal (PhC) slabs provide efficient ways to manipulate light at the nanoscale through small group-velocity modes with low radiation losses. The resonant modes in periodic photonic lattices are predominantly limited by nonleaky guided modes at the boundary of the Brillouin zone below the light cone. Here, we propose a mechanism for ultra-high Q resonators based on the bound states in the continuum (BICs) above the light cone that have zero-group velocity (ZGV) at an arbitrary Bloch wavevector. By means of the mode expansion method, the construction and evolution of avoided crossings and Friedrich-Wintgen BICs are theoretically investigated at the same time. By tuning geometric parameters of the PhC slab, the coalescence of eigenfrequencies for a pair of BIC and ZGV modes is achieved, indicating that the waveguide modes are confined longitudinally by small group-velocity propagation and transversely by BICs. Using this mechanism, we engineer ultra-high Q nanoscale resonators that can significantly suppress the radiative losses, despite the operating frequencies above the light cone and the momenta at the generic k point. Our work suggests that the designed devices possess potential applications in low-threshold lasers and enhanced nonlinear effects.

17.
Chin Herb Med ; 16(2): 231-234, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38706828

ABSTRACT

Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological activities. Methods: The chemical constituents were isolated and purified by combining with ODS column chromatography, silica gel column chromatography and by performing semipreparative HPLC. Their structures were established on the basis of 1D NMR (1H-NMR and 13C-NMR) and 2D NMR (1H-1H COSY, HSQC, HMBC and NOESY), as well as HRESIMS and comparison with literature data. In addition, the absolute configuration of compound 1 was determined by calculated ECD data. Results: One previously undescribed tetracyclic triterpenoid derivative, named as integracide L (1), 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8,14-diene-2α,3ß,11ß-triol (2), 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8-momoene-2α,3ß,11ß-triol (3), 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8,14-diene-3ß,11ß-triol (4), and 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8-momoene-3ß,11ß-triol (5) were isolated from F. sporotrichioide. Moreover, compound 1 was rare tetracyclic triterpenoid with single methyl replacement at C-4 position. Conclusion: Compound 1 was a new tetracyclic triterpenoid isolated from the endophytic fungus F. sporotrichioides. In addition, compound 2 could inhibit the growth of three different human cancer cells significantly. Compounds 3 and 5 were found to possess better cytotoxic activities on HepG-2 cells than the other compounds, with IC50 values of (2.8 ± 0.1) and (6.3 ± 0.3) µmol/L respectively.

18.
Heliyon ; 10(9): e30255, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38707326

ABSTRACT

This study investigated the physicochemical and flavor quality changes in fresh-cut papaya that was stored at 4 °C. Multivariate statistical analysis was used to evaluate the freshness of fresh-cut papaya. Aerobic plate counts were selected as a predictor of freshness of fresh-cut papaya, and a prediction model for freshness was established using partial least squares regression (PLSR), and support vector machine regression (SVMR) algorithms. Freshness of fresh-cut papaya could be well distinguished based on physicochemical and flavor quality analyses. The aerobic plate counts, as a predictor of freshness of fresh-cut papaya, significantly correlated with storage time. The SVMR model had a higher prediction accuracy than the PLSR model. Combining flavor quality with multivariate statistical analysis can be effectively used for evaluating the freshness of fresh-cut papaya.

19.
J Med Chem ; 67(10): 8420-8444, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38718180

ABSTRACT

Faced with increasingly serious fungal infections and drug resistance issues, three different series of novel dual-target (programmed death ligand 1/14 α-demethylase) compounds were constructed through the fragment combination pathway in the study. Their chemical structures were synthesized, characterized, and evaluated. Among them, preferred compounds 10c-1, 17b-1, and 18b-2 could efficiently exert their antifungal and antidrug-resistant fungal ability through blocking ergosterol biosynthesis, inducing the upregulation of reactive oxygen species level, and triggering apoptosis. Especially, compound 18b-2 exhibited the synergistic function of fungal inhibition and immune activation. Moreover, the covalent organic framework carrier was also generated based on the acidic microenvironment of fungal infection to improve the bioavailability and targeting of preferred compounds; this finally accelerated the body's recovery rate.


Subject(s)
Antifungal Agents , Antifungal Agents/pharmacology , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Humans , Animals , Microbial Sensitivity Tests , Structure-Activity Relationship , Reactive Oxygen Species/metabolism , Apoptosis/drug effects , 14-alpha Demethylase Inhibitors/pharmacology , 14-alpha Demethylase Inhibitors/chemistry , 14-alpha Demethylase Inhibitors/chemical synthesis , Mycoses/drug therapy , Mice , Candida albicans/drug effects , Ergosterol/metabolism , Molecular Structure
20.
Materials (Basel) ; 17(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38730833

ABSTRACT

Flow-accelerated corrosion (FAC) preferentially attacks the downstream heat-affected zone of the root-pass weld in steam pipe systems. A detailed characterization identifies the fusion boundary as the initiation location for the attack. Alloying elements are found depleted along the weld fusion boundary, and multiple welding thermal cycles and repetitive austenite-to-ferrite phase transformations result in an increased proportion of grains with Goss {110}<001> texture along the fusion boundary. The synergistic effects of chemical segregation and the Schmid factor may contribute to the preferential initiation of FAC cracks along the root weld fusion boundary, making it the weakest link for FAC attack in steam pipe girth welds.

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