Search

The degradation and desertification of grassland ecosystems have garnered significant attention both domestically and internationally. Grassland restoration techniques are widely considered a principal measure to promote the sustainable utilization of grasslands, with soil nutrient content being a core indicator for assessing the effectiveness of restoration in degraded grasslands. This study aims to explore the differential impacts of various grassland restoration methods on soil nutrient distribution in degraded Stipa grandis grasslands. Three major restoration methods, i.e., root cutting, enclosure, and fertilization, were applied in the study area. The soil nutrient content was measured and analyzed under the different restoration methods and at varying depths. The results revealed that under all three restoration methods and at different soil depths (0–10 cm, 10–20 cm, 20–30 cm), the organic matter, total nitrogen, total phosphorus, alkali-hydrolyzable nitrogen, alkali-hydrolyzable phosphorus, and available potassium contents were significantly higher than those in the control group (p < 0.05). Furthermore, as soil depth increased, the contents of organic matter and all nutrients gradually decreased. Specifically, regarding the contents of different nutrients, the order of organic matter, total nitrogen, total phosphorus, alkali-hydrolyzable nitrogen, and available phosphorus was as follows: fertilization > enclosure > root cutting > control, while the contents of total potassium and available potassium followed the sequence: fertilization > enclosure > control > root cutting. Additionally, based on the canonical correlation analysis (R2 = 0.88), the total phosphorus content in soil had the greatest impact on soil nutrients, while vegetation cover and plant height contributed the most to vegetation characteristics. In grassland restoration, the increase in soil total phosphorus led to higher vegetation cover and height, mildly influenced plant diversity and density, and simultaneously promoted biomass accumulation. These research findings provide a solid theoretical foundation for the application of grassland restoration techniques, contributing to the sustainable development of grassland ecosystems. [ABSTRACT FROM AUTHOR]

Peony seed dreg protein (PSDP) was hydrolyzed by proteases secreted by Pseudoalteromonas sp. CSN423. This hydrolysate exhibited excellent antioxidant capability after passing through a 3 kDa ultrafiltration membrane. The antioxidant peptides further purified by size-exclusion chromatography scavenged 2, 2-diphenyl-1-picrylhydrazyl (DPPH∙) (73.0 ± 1.46%) and hydroxyl radicals (∙OH) (81.17 ± 3.69%), protected DNA from oxidative injury, and displayed an oxygen radical absorbance capacity (ORAC) of 4.04 ± 1.11 μmol TE/mg. Furthermore, the antioxidant peptide inhibited apoptosis by inhibiting the production of reactive oxygen species (ROS) and the decrease of mitochondrial membrane potential in H2O2-induced RAW264.7 cells. We identified four major peptides such as YFPF, ECCASLAPL, YVSLK, and YFEM by using mass spectrometry. YFPF showed a potent ∙OH scavenging capability of 75.30 ± 1.08%. ECCASLAPL exhibited higher DPPH∙ scavenging capability (87.20 ± 1.03%) than glutathione (GSH) (49.50 ± 1.50%). Moreover, the peptide YVSLK exhibited the highest ORAC of 2.52 ± 1.20 μmol TE/mg of the identified peptides. This work highlights that the peptides from PSDP might have potential uses in cosmetics, functional foods, and drug development. [ABSTRACT FROM AUTHOR]

• Deferasirox greatly enhanced the accumulated PpIX in 5-ALA-treated OTSCC cells through iron chelation. • Deferasirox promoted 5-ALA-based PDT against OTSCC both in vitro and in vivo. • Combination of 5-ALA-based PDT with iron chelation maybe a promising strategy for OTSCC therapy. Oral tongue squamous cell carcinoma (OTSCC) is the most common malignancy of the oral cavity. Photodynamic therapy (PDT) has become a clinically promising approach for early stage OTSCC treatment. 5-Aminolaevulinic acid (5-ALA) is a precursor of protoporphyrin IX (PpIX) and has been applied for PDT of cancer. However, the accumulated PpIX in 5-ALA-treated cancer cells will be further transformed into heme through ferrous iron insertion under ferrochelatase catalysis. Theoretically, iron chelation can enhance the intracellular accumulation of PpIX and thus promote 5-ALA-based PDT. Here, an iron chelator deferasirox (DFX) was used to investigate synergistic suppression effects of 5-ALA-based PDT and iron chelation on OTSCC. In OTSCC SCC-25 cells, the enhancing effect of DFX on 5-ALA-mediated accumulation of PpIX was firstly assessed. After laser irradiation (635 nm, 200 mW/cm2 and 2 min), the synergistic cytotoxicity and apoptosis-inducing effect of 5-ALA and DFX were evaluated in SCC-25 cells, and the apoptosis mechanism was further investigated by monitoring the change of mitochondrial membrane potential and observing the subcellular localization of cytochrome c (Cyt c). In SCC-25 tumor-bearing mice, the synergistic suppression effects of 5-ALA-based PDT and DFX on tumor growth and tumor angiogenesis were investigated after laser irradiation on the tumor (635 nm, 150 mW/cm2 and 10 min). In SCC-25 cells, DFX showed strong iron chelation effect and enhanced 5-ALA-mediated intracellular accumulation of PpIX by 2–3 folds. After laser irradiation (635 nm, 200 mW/cm2 and 2 min), 5-ALA combined with DFX exhibited significant synergistic effects on cytotoxicity and cell apoptosis. In the treated cells, the damage of mitochondrial membrane and the release of Cyt c from mitochondria to cytoplasm were observed distinctly, indicating the activation of mitochondria-related signal pathway. In SCC-25 tumor-bearing mice, tumor growth and tumor angiogenesis were both notably suppressed by combination treatment of 5-ALA with laser irradiation and DFX. Meanwhile, no obvious toxic injuries were visible in histological examination of major organs in the treated mice. 5-ALA-based PDT combined with iron chelation synergistically inhibited the growth of OTSCC. Hence it can be seen that this combination therapy may represent a promising strategy for clinical treatment of OTSCC and other cancers. [ABSTRACT FROM AUTHOR]

HN-1, a 12-amino acid peptide, has been reported to possess strong capabilities for targeting and penetrating head and neck squamous cell carcinoma. Here, we designed a simple but effective nanoparticle system for the delivery of doxorubicin (DOX) targeting oral squamous cell carcinoma (OSCC) through the mediation of HN-1. PEGylated DOX (PD) was firstly synthesized by the conjugation of DOX with bis-amino-terminated poly(ethylene glycol) via succinyl linkage, and then PD nanoparticles were prepared by a modified nanoprecipitation method. After that, PD nanoparticles were surface-modified with HN-1 to form HNPD nanoparticles, which had a uniform spherical shape and a small size about 150 nm. In human OSCC cells (CAL-27 and SCC-25), HNPD nanoparticles exhibited significantly higher cellular uptakes and cytotoxicities than PD nanoparticles. Furthermore, HNPD nanoparticles showed a certain degree of functional selectivity for CAL-27 and SCC-25 cells as compared to human hepatoma HepG2 cells. In SCC-25 tumor-bearing nude mice, HNPD nanoparticles showed remarkably enhanced tumor-targeting and penetrating efficiencies as compared to PD nanoparticles, and effectively inhibited the tumor growth. In conclusion, our study demonstrated for the first time that HN-1 could be used for mediating the OSCC-targeted delivery of nanoparticles. [ABSTRACT FROM AUTHOR]

Background: The relationship between oxidative balance score (OBS) and diabetes remains poorly understood and may be gender-specific. We conducted a cross-sectional study to investigate the complex association between OBS and diabetes among US adults., Methods: Overall, 5,233 participants were included in this cross-sectional study. The exposure variable was OBS, composed of scores for 20 dietary and lifestyle factors. Multivariable logistic regression, subgroup analysis, and restricted cubic spline (RCS) regression were applied to examine the relationship between OBS and diabetes., Results: Compared to the lowest OBS quartile group (Q1), the multivariable-adjusted odds ratio (OR) (95% confidence interval (CI) for the highest OBS quartile group (Q4) was 0.602 (0.372-0.974) ( p for trend = 0.007), and for the highest lifestyle, the OBS quartile group was 0.386 (0.223-0.667) ( p for trend < 0.001). Moreover, gender effects were found between OBS and diabetes ( p for interaction = 0.044). RCS showed an inverted-U relationship between OBS and diabetes in women ( p for non-linear = 6e-04) and a linear relationship between OBS and diabetes in men., Conclusions: In summary, high OBS was negatively associated with diabetes risk in a gender-dependent manner., Competing Interests: The authors declare that this study was conducted in the absence of any commercial or financial relationships that could serve as a potential conflict of interest., (Copyright © 2023 Wu, Ren, Song, Gao, Pang and Zhang.)

In this study, a reactive oxygen species (ROS)-responsive nanoparticle system was designed for combining photodynamic therapy (PDT) and chemotherapy for oral tongue squamous cell carcinoma (OTSCC)-targeted treatment. A PEGlated prodrug (RPTD) of doxorubicin (DOX) via thioketal linkage and cRGD peptide modification was synthesized and then used to prepare nanoparticles for encapsulating photosensitizer hematoporphyrin (HP). Thus, the obtained HP-loaded RPTD (RPTD/HP) nanoparticles had a regular spherical shape and small size, approximately 180 nm. The RPTD/HP nanoparticles showed a remarkable PDT efficiency and successfully induced ROS generation upon laser irradiation both in vitro and in vivo. DOX exhibited significant ROS-responsive release property from RPTD/HP nanoparticles because of the rupture of the thioketal linker. In OTSCC cells, RPTD/HP nanoparticles were efficiently internalized and showed potent effects on cell growth inhibition and apoptosis induction after laser irradiation. In OTSCC tumor-bearing mice, RPTD/HP nanoparticles displayed excellent tumor-targeting ability and notably suppressed tumor growth through multiple mechanisms after local laser irradiation. Taken together, we supplied a novel therapeutic nanosystem for OTSCC treatment through combining PDT and chemotherapy.

Epithelial‑to‑mesenchymal transition (EMT) may result in damage to the peritoneum and the development of fibrosis in peritoneal mesothelial cells (PMCs). However, the mechanism underlying EMT in peritoneal mesothelial cells is not well understood. Heat shock proteins (HSPs) were initially identified as proteins that are expressed following exposure of cells to environmental stress. However, their function in the development of EMT in PMCs remains to be fully elucidated. In the present study, the effect of HSP70 on advanced glycation end‑products (AGEs)‑induced EMT in peritoneal mesothelial cells was investigated by overexpression of this protein using a plasmid and knockdown of HSP70 using small interfering RNA. In addition, the underlying molecular mechanisms were explored. The results demonstrated that AGEs activated changes associated with EMT, including the loss of E‑cadherin and the increase in α‑smooth muscle actin. Furthermore, AGEs also induced the upregulation of HSP70, which led to the partial inhibition of EMT in PMCs. HSP70 inhibits EMT by modulating transforming growth factor‑β (TGF‑β)/Smad expression and the mitogen‑activated protein kinases (MAPK)/extracellular signal‑regulated kinases (ERK) signaling pathways. The findings suggested that HSP70 augments the cellular defense capacity through inhibition of TGF‑β/Smad and MAPK/ERK signaling pathways, thereby protecting PMCs from AGEs‑induced EMT.

Renal tubular epithelial cells can enter the epithelial‑to‑mesenchymal transition (EMT) in response to chronic hypoxia. EMT is a process which involves the phenotypic conversion of epithelial cells, that is believed to have an important role in renal fibrosis. However, the underlying mechanisms of the involvement of EMT in renal fibrosis remain to be elucidated. Adrenomedullin (AMD) has been implicated in renal fibrosis and is induced by hypoxia. The aims of the present study were to determine whether ADM signaling was active in human proximal tubular epithelial cells cultured under hypoxic conditions, and to observe the activity of ADM during EMT. The expression levels of ADM were significantly increased, in a time‑dependent manner, in HK‑2 and HKC human proximal tubular epithelial cells, cultured under hypoxic conditions. Overexpression of exogenous ADM was accompanied by increased expression levels of the epithelial markers E‑cadherin and tight junction protein‑1, and decreased expression levels of the mesenchymal markers vimentin and α‑smooth muscle actin, during hypoxia. Knock‑down of ADM expression by small hairpin RNA, or co‑administration of an ADM peptide inhibitor, in HK‑2 cells significantly exacerbated hypoxia‑induced EMT, as compared to the lack of effect observed in the untransfected controls. ADM was shown to suppress EMT by inhibiting the activation of extracellular signal‑regulated kinase (ERK), and this effect was prevented by the ERK activator apigenin. The results of the present study suggest that ADM has an important role in promoting EMT in hypoxic human proximal tubular epithelial cells. ADM may therefore represent a novel therapeutic target in the treatment of injured kidneys.

The cyclic resistance of ProTaper Universal (size 25/08) and ProTaper Next (size 25/06) instruments was compared in artificial canals with different curvatures in this study. A total of 30 ProTaper Universal and 30 ProTaper Next instruments were divided into 6 groups (n = 10) and were operated into artificial canals with 3 different angles of curvature (45°, 60°, 90°). The canal length was kept consistent in this study. The number of cycles to fracture (NCF) was counted until file fracture occurred, at which point, the length of the fragment was measured. The data were analyzed statistically using ANOVA complemented by the Tukey test (p < 0.05). Cross sections of the fractured files were scanned by an electron microscope. In the fatigue test, the ProTaper Next displayed more resistance in 45° and 60° canals (p < 0.05), whereas ProTaper Universal exhibited a better operability in 90° canals (p < 0.05). The average length of the fragments from ProTaper Next was significantly shorter than that from ProTaper Universal in 90° canals (p < 0.05). The cross sections of the fractured surfaces became flatter when the curvature angles decreased from 90° to 45°. ProTaper Next was more reliable when shaping in curved canals, whereas ProTaper Universal was more sui for the preparation of root canals with severe curvatures.

Conventional liposomes (CLs) have been used as a transdermal drug delivery system for enhancing the delivery of hydrophilic drugs into/through the skin. However, their applications have been constrained by their limited penetration ability and poor stability. In this article, a new kind of transactivating transcriptional activator peptide (TAT)-conjugated polymeric lipid vesicles (TPLVs) formed from amphiphilic lysine-linoleic acid modified dextran (LLD) and cholesterol (Chol) has been prepared successfully. The newly developed TPLVs had a bilayer structure similar to CLs. The TPLVs also have smaller particle size, narrower distribution, higher positive charge and much better stability than the CLs; they remained stable in aqueous solutions for up to 60 days without aggregation. The in vitro and in vivo skin permeation studies revealed that TPLVs delivered a higher amount of drug through the skin than CLs, indicating enhanced drug transdermal activities. The synergetic effects of abovementioned features and the cell-penetrating peptide TAT might have contributed to the improved skin penetration ability of the TPLVs. Similar to CLs, TPLVs began to show limited cytotoxicity against human umbilical vein endothelial cells at a concentration of 200 μg mL -1 . The in vitro release profiles showed that the TPLVs achieved a sustained release of lidocaine. These results suggest that the TPLVs may be utilized as an efficient carrier to replace CLs for transdermal drug delivery.