Contributions of soil organic carbon-induced root- and soil properties complexity to water flow in eastern China.

Water flow within the soils affects the efficiency of materials transfer mediated by water. Soil organic carbon (SOC) as an important role in active water flow events can drive the complexity of root-soil synthesis by improving root and soil properties. However, contributions of SOC-induced root- and soil properties complexity to water flow are not well understood. In this study, dye tracing experiments at the three forest stands (oak, pine, and bamboo forests) were conducted to explore water flow patterns, i.e., preferential flow paths (PFP), stream buffer zones (SBZ), and water flow zones (WFZ). X-ray microtomography (CT) scanning was performed to reconstruct the root architecture. The partial least squares path model was applied to quantitatively explore the effects of root- and soil properties on water flow. The results showed that the index of water flow connectivity (IWFC) in the PFP and WFZ patterns decreased with increasing soil depth, while IWFC in the SBZ pattern increased at first and then decreased. In the PFP pattern, soil physical properties had the larger total effects (TE = 0.624) on IWFC change compared with root properties (TE = 0.257). In the SBZ pattern, the total effects of root properties controlling IWFC change (TE = 0.510) were greater than soil physical properties (TE = -0.386). Both of them can equally affect the IWFC in the WFZ pattern. In conclusion, the influences of SOC by driving the changes of soil properties on gravity-driven convective flow process were dramatically stronger than root properties, while SOC could primarily drive the changes of root properties and thereby affect capillary-driven convective flow process. The present results can provide a scientific basis for sustainable forestry management and also a better understanding of the forestry hydrology.

Selenium-Doped Nanoheterojunctions for Highly Efficient Cancer Radiosensitization.

Exploring efficient and low-toxicity radiosensitizers to break through the bottleneck of radiation tolerance, immunosuppression and poor prognosis remains one of the critical developmental challenges in radiotherapy. Nanoheterojunctions, due to their unique physicochemical properties, have demonstrated excellent radiosensitization effects in radiation energy deposition and in lifting tumor radiotherapy inhibition. Herein, they doped selenium (Se) into prussian blue (PB) to construct a nano-heterojunction (Se@PB), which could promote the increase of Fe2+/Fe3+ ratio and conversion of Se to a high valence state with Se introduction. The Fe2+-Se-Fe3+ electron transfer chain accelerates the rate of electron transfer on the surface of the nanoparticles, which in turn endows it with efficient X-ray energy transfer and electron transport capability, and enhances radiotherapy physical sensitivity. Furthermore, Se@PB induces glutathione (GSH) depletion and Fe2+ accumulation through pro-Fenton reaction, thereby disturbs the redox balance in tumor cells and enhances biochemical sensitivity of radiotherapy. As an excellent radiosensitizer, Se@PB effectively enhances X-ray induced mitochondrial dysfunction and DNA damage, thereby promotes cell apoptosis and synergistic cervical cancer radiotherapy. This study elucidates the radiosensitization mechanism of Se-doped nanoheterojunction from the perspective of the electron transfer chain and biochemistry reaction, which provides an efficient and low-toxic strategy in radiotherapy.

Moso bamboo (Phyllostachys edulis) expansion enhances soil pH and alters soil nutrients and microbial communities.

Amid global environmental concerns, the issue of bamboo expansion has garnered significant attention due to its extensive and profound impacts on the ecosystems. Bamboo expansion occurs in native and introduced habitats worldwide, particularly in Asia. However, the effects of bamboo expansion on soil pH, nutrient levels, and microbial communities are complex and vary across different environments. To address this knowledge gap, we conducted a meta-analysis with 2037 paired observations from 81 studies. The results showed that soil pH increased by 6.99 % (0-20 cm) and 4.49 % (20-40 cm) after bamboo expansion. Notably, soil pH increased more in the coniferous forest with bamboo expansion than in the broadleaf forest. Soil pH progressively increased over time since the establishment of bamboo stands. The extent of soil pH elevation was significantly positively correlated with the proportion of bamboo within the forest stand and mean annual solar radiation. In contrast, it was significantly negatively correlated with the mean annual temperature. The elevation of pH is closely related to expansion stage and expanded forest type rather than primarily shaped by climatic factors across a large scale. We also found that bamboo expansion into coniferous forests brought about a notable 14.14 % reduction in total nitrogen (TN). Varied expansion stages resulted in TN reductions of 6.88 % and 7.99 % for mixed forests and bamboo stands, respectively, compared to native forests. Pure bamboo stands exhibited a remarkable 30.39 % increase in ammonium nitrogen and a significant 21.12 % decrease in nitrate nitrogen compared to their native counterparts. Furthermore, bamboo expansion contributed to heightened soil fungal diversity. Taken together, our findings highlight that bamboo expansion leads to an increase in soil pH and alters soil N components and fungal microbial communities, providing valuable insights for future ecological conservation and resource management.

Translational Selenium Nanoparticles to Attenuate Allergic Dermatitis through Nrf2-Keap1-Driven Activation of Selenoproteins.

Easy recurrence and strong treatment side effects significantly limit the clinical treatment of allergic dermatitis. The human trace element selenium (Se) plays essential roles in redox regulation through incorporation into selenoproteins in the form of 21st necessary amino acid selenocysteine, to participates in the pathogenesis and intervention of chronic inflammatory diseases. Therefore, based on the safe and elemental properties of Se, we construct a facile-synthesis strategy for antiallergic selenium nanoparticles (LET-SeNPs), and scale up the production by employing a spray drying method with lactose (Lac-LET-SeNPs) or maltodextrin (Mal-LET-SeNPs) as encapsulation agents realizing larger scale production and a longer storage time. As expected, these as-prepared LET-SeNPs could effectively activate the Nrf2-Keap1 signaling pathway to enhance the expression of antioxidative selenoprotein at mRNA and protein levels, then inhibit mast cell activation to achieve efficient antiallergic activity. Interestingly, LET-SeNPs undergo metabolism to seleno-amino acids to promote biosynthesis of selenoproteins, which could suppress ROS-induced cyclooxygenase-2 (COX-2) and MAPKs activation to suppress the release of histamine and inflammatory cytokines. Allergic mouse and Macaca fascicularis models further confirm that LET-SeNPs could increase the Se content and selenoprotein expression in the skin, decrease mast cells activation and inflammatory cells infiltration, and finally exhibit the high therapeutic effects on allergic dermatitis. Taken together, this study not only constructs facile large-scale synthesis of translational Se nanomedicine to break through the bottleneck problem of nanomaterials but also sheds light on its application in the intervention and treatment of allergies.

Deciphering superior quality of Pu-erh tea from thousands of years' old trees based on the chemical profile.

Pu-erh teas from thousands of years' old trees (TPT) equip with both superior flavors and powerful antioxidative capacities. With UHPLC-Q-TOF-MS approach, TPTs' chemical profiles were characterized by comparing with Pu-erh teas from ecological trees (EPT). TPTs are discovered to possess higher contents of amino acids, fatty acids, phenolic acids, nucleosides and nucleobases but lower contents of flavonoids and caffeine congeners based on 117 discriminative constituents from 305 identified ones. Particularly, a series of caffeic acid congeners including ten new hydroxycinnamic acid depsides with higher contents in TPTs are discovered, and caffeic acid with a fold change of 638 is the foremost discriminative component. Furthermore, distinguishing constituent proportion including caffeic acid congeners in TPTs are found to take great responsibilities for their more powerful antioxidative abilities and superior flavors especially more aroma and pleasant bitterness. This research provides information for deciphering formation of TPTs' superior qualities based on chemical profile.

Prevention of hematoma on the floor of the mouth during dental implant surgery in the anterior mandible / 口腔疾病防治

Objective@# To explore the cause and preventive measures of floor-of-mouth hematoma after dental implant placement. @*Methods@#The prevention of hematoma of the floor of the mouth in a case of lower anterior teeth implant placement was analyzed, and the literature was reviewed.@*Results@# Four mandibular vascular canals were found on the lingual side of the anterior mandible before dental surgery in the reported case. Two of them were quite thick (1.4 mm and 1.0 mm, respectively) and were located adjacent to the crest of the alveolar bone and superior to the mental spine. These two thick endosseous branches from the sublingual artery were dissected and ligated , and there was no obvious hematoma in the patients immediately after the operation and at the postoperative 3 d review. The results of the literature review show that the incidence of endosseous branches from the lingual vascular canal of the mandible is 90%-100%. The distribution of the vessels on the lingual side of the mandible is highly variable and adjacent to the lingual cortical plate. Accidental injury of the lingual cortical plate during implant surgery would probably lead to bleeding or hematoma on the floor of the mouth. @*Conclusion @#Mastering the anatomy of blood vessels on the floor of the mouth, elaboratively examining preoperative three-dimensional radiographic imaging, and cautiously exploring the lower jaw bone morphology after flap elevation are preventive measures to avoid damage to the arterial supply on the lingual side of the anterior lower jaw and to prevent complications of hematoma in the floor of the mouth.

[Biologic effects of advanced oxidative protein products on the human gingival fibroblasts].

OBJECTIVE: To investigate the effects of advanced oxidative protein products (AOPP) on the proliferation, apoptosis and matrix metalloproteinase-1 (MMP-1) synthesis of the human gingival fibroblast (HGF). To explore the possible mechanism of the periodontal destruction acceleration in diabetes through AOPP-mediated oxidative stress. METHODS: HGF were isolated by both tissue explant cultivation technique and enzyme digestion method. The culture media with 5, 50, 100 mg/L AOPP-HAS were added into each experimental group, but the culture media in the control group didn't contain AOPP-HAS. MTT colorimetric assay and ELISA were used to measure the changes of HGF proliferation and the levels of MMP-1 protein from HGF at different time periods, respectively. Seventy-two hours after co-culture with 50 mg/L AOPP-HSA, cell apoptosis was detected by flow cytometry with Annexin V/PI staining. RESULTS: Compared to the control group, the growth inhibition rate of HGF in 5, 50, 100 mg/L AOPP-HSA group was significantly different (P < 0.05). The peak value appeared at 48 hours of co-culture [(19.01 +/- 6.28)%, (30.48 +/- 5.75)%, (39.75 +/- 4.60)%, respectively]. There was a dose-dependent relationship between the growth inhibition rate and AOPP-HSA. No significant difference was detected on the apoptotic level between experimental group and the control (P > 0.05). The MMP-1 synthesis in 0.5, 5, 50, 100 mg/L AOPP-HAS group [(55.61 +/- 1.06), (65.78 +/- 4.04), (79.24 +/- 3.09), (89.76 +/- 28.88) mg/L, respectively] was significantly higher than that in the control [(34.90 +/- 3.15) mg/L] after 72 hours co-culture (P < 0.05). There was a dose-dependent relationship between MMP-1 and AOPP-HSA. CONCLUSIONS: AOPP may inhibit the proliferation of HGF and such effect was not achieved through apoptosis. AOPP may increase collagen degradation by promoting MMP-1 synthesis and thus may accelerate periodontal destruction process in diabetes.

[MGB probes detect Streptococcus mutans and Streptococcus sobrinus in real time].

OBJECTIVE: To detect and distinguish Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus) quickly in epidemiology and investigate the distribution of S. mutans in the oral of children with rampant caries. METHODS: Designed minor groove binder (MGB) probes according to the gtf gene of S. mutans and S. sobrinus. Detected 9 reference strains of Streptococcus mutans group by MGB probes in real time and after cultivation. Evaluated the results of these two methods. 92 dental plaques from pre-school children with rampant caries were detected in real time with MGB probes. RESULTS: The primers could amplify the target sequences specificity and distinguished S. mutans and S. sobrinus from each other using MGB probes. Though the fluorescence occurred earlier in S. mutans than in S. sobrinus, they had the same results in nature. In 92 children with rampant caries, the detective ratio of S. mutans was 96.7% and that of S. sobrinus was 32.6%. All the samples which could detect S. sobrinus were positive for S. mutans. CONCLUSION: The primers and probe designed from gtf genes of S. mutans and S. sobrinus can amplify the target sequence and distinguish them from each other in real time.