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Simple Summary: To better protect and manage the germplasm resources of the topmouth culter (Culter alburnus), it is important to explore the current status of its genetic diversity. In this study, the mitochondrial DNA COI gene was used to analyze the genetic diversity, genetic differentiation, and historical dynamics of C. alburnus from five river basins in north and south China. The results showed that the genetic diversity is polarized in different populations but without new species differentiation and has significant geographical features, which are important for developing conservation strategies. To study the genetic diversity of Culter alburnus (C. alburnus) populations, we analyzed the genetic diversity of five C. alburnus populations from Songhua Lake (SH), Huaihe River (HH), Changjiang River (CJ), Taihu Lake (TH), and Gehu Lake (GH) based on mitochondrial COI gene sequences. The results showed that the average contents of bases T, C, A, and G in the 526 bp COI gene sequence were 25.3%, 18.1%, 28.1%, and 28.6%, respectively, which showed AT bias. A total of 115 polymorphic sites were detected in the five populations, and 11 haplotypes (Hap) were defined. The nucleotide diversity (Pi) of the five populations ranged from 0.00053 to 0.01834, and the haplotype diversity (Hd) ranged from 0.280 to 0.746, with the highest genetic diversity in the TH population, followed by the SH population, with lower genetic diversity in the HH, CJ and GH populations. The analysis of the fixation index (Fst) and the genetic distance between populations showed that there was significant genetic differentiation between the SH population and the other populations, and the genetic distances between all of them were far; the genetic diversity within populations was higher than that between populations. Neutral tests, mismatch distributions, and Bayesian skyline plot (BSP) analyses showed that the C. alburnus populations have not experienced population expansion and are relatively stable in historical dynamics. [ABSTRACT FROM AUTHOR]

Background and objective: Psychological stress causes structural and metabolic dysfunction of masseter muscles. The anti‐inflammatory and anti‐oxidative polyphenol curcumin plays a local antioxidant role in rat masseter muscles under psychological stress by an as‐yet‐unknown mechanism. The present study aimed to assess curcumin anti‐inflammatory and anti‐oxidative effects on masseter muscle and its possible molecular mechanisms. Methods: We constructed a rat model of chronic unpredictable moderate stress (CUMS). Psychological stress was assessed by determining the levels of adrenocorticotropic hormone (ACTH) and cortisol in serum. Enzyme‐linked immunosorbent assays measured inflammatory cytokines and markers of oxidative stress in masseter muscles. Levels of high‐mobility group box 1 (HMGB1), interleukin (IL)‐1β, IL‐6 and tumour necrosis factor‐alpha (TNF‐α) were determined using quantitative PCR analyses and immunofluorescent staining. Toll‐like receptor 4 (TLR4) and nuclear factor kappa B (NF‐κB) activation were examined using western blotting. Results: The CUMS group showed increased serum cortisol and ACTH levels. Pathological changes in the ultrastructure, oxidative stress and inflammatory cytokines in the masseter muscles were also observed. Curcumin treatment (50, 100 mg/kg) ameliorated these changes significantly by varying degrees. Mechanistically, increased levels of phosphorylated NF‐κB, toll‐like receptor 4 and HMGB1 were observed, which were also ameliorated by curcumin treatment. Conclusion: Curcumin can reduce local pathological changes, levels of oxidative stress and inflammatory factors in masseter muscles. Psychological stress activates HMGB1 expression and increases the expression of downstream TLR4 and p‐NF‐κB, which could be reduced by curcumin. Thus, curcumin might exert anti‐inflammatory and antioxidant effects in masseter muscles via the HMGB1/TLR4/NF‐κB pathway. [ABSTRACT FROM AUTHOR]

The rational design and fabrication of nanostructures has become a fashionable strategy for pursing high thermoelectric performance in solid-state materials. Here we report nanostructured Te–Sb2Te3 composites with significantly enhanced thermoelectric performance through a scalable bottom-up method followed by a rapid sintering process. The power factor along with the carrier concentration could be significantly enhanced by increasing the number of point defects of UGRAPHIC DISPLAY="INLINE" ID="UGT1" SRC="UGT1"/. Meanwhile, a great number of boundaries and hetero-interfaces between the Te and Sb2Te3 nanoparticles could play an important role in blocking phonons, resulting in the evident suppression of lattice thermal conductivity. Ultimately, a highest zT value close to 1.0 could be achieved at 623 K in samples with components of 2.6 mol% Sb2Te3 and 97.4 mol% Te. Such a peak zT value is comparable to that of doped Te materials synthesized by the conventional solid-state reaction process. This work reveals that high thermoelectric performance could be realized in an intentionally designed nanocomposite by synergistically improving the power factor and suppressing the lattice thermal conductivity. [ABSTRACT FROM AUTHOR]

Objective: To explore the effect of long-term stress on the temporomandibular joint (TMJ) condyle and its possible underlying mechanism., Methods: A 12-week, chronic unpredictable mild stress (CUMS) model was used to induce long-term psychological stress in rats. Rats were randomly divided into control group (CONT), chronic unpredictable mild stress group (CUMS) and chronic unpredictable mild stress with fluoxetine treatment group (CUMS + DT) (n = 30 per group). A 5 mg/kg dose of fluoxetine was intraperitoneally injected daily 0.5 h before stress. A sucrose preference test, plasma corticosterone test and open-field test were performed to verify the feasibility of the CUMS model. Histopathology was used to observe the pathological changes of condyle. The expression levels of inflammatory cytokines, matrix metalloproteases (MMPs) and extracellular matrix (ECM) were measured by real-time polymerase chain reaction, western blotting and immunohistochemistry., Results: At 8 and 12 weeks after exposure to CUMS, the rats showed higher plasma corticosterone than the control rats. Additionally, for the open-field test, the rats exposed to CUMS spent more time in the centre zone and moved a shorter distance than the control and drug treatment rats. In addition, pathological changes in the condylar cartilage occurred in the 8-week CUMS subgroup and were more obvious in the 12-week CUMS subgroup. The CUMS caused an increase in the secretion of inflammatory cytokines, imbalanced expression of MMPs and tissue inhibitor of metalloproteinase-1 and accelerated degradation of ECM in condylar cartilage in a time-dependent manner., Conclusion: Osteoarthritis-like lesions can be caused by long-term CUMS in the mandibular condyles, which suggests that the imbalance in chondrocyte-secreted regulatory factors within the cartilage of the TMJ may play an important role in cartilage injury induced by psychological stress.