Mechanisms by which sheep milk consumption ameliorates insulin resistance in high-fat diet-fed mice.

Sheep milk is rich in fat, protein, vitamins and minerals and is also one of the most important sources of natural bioactives. Several biopeptides in sheep milk have been reported to possess antibacterial, antiviral and anti-inflammatory properties, and they may prevent type 2 diabetes (T2D), disease and cancer. However, the precise mechanism(s) underlying the protective role of sheep milk against T2D development remains unclear. Therefore, in the current study, we investigated the effect of sheep milk on insulin resistance and glucose intolerance in high-fat diet (HFD)-fed mice, by conducting intraperitoneal glucose tolerance tests, metabolic cage studies, genomic sequencing, polymerase chain reaction, and biochemical assays. Hyperinsulinemic-euglycemic clamp-based experiments revealed that mice consuming sheep milk exhibited lower hepatic glucose production than mice in the control group. These findings further elucidate the mechanism by which dietary supplementation with sheep milk alleviates HFD-induced systemic glucose intolerance.

Static gain estimation for nonlinear dynamic systems from steady-state values hidden in historical data.

Static gains are often required for control, diagnosis and optimization of nonlinear dynamic systems. This paper proposes a new approach to estimate static gains for nonlinear dynamic systems from steady-state values hidden in historical data. First, steady-state values of system inputs and outputs are extracted by automatically finding data segments in steady-state conditions. Second, static gains of nonlinear dynamic systems in different operating conditions are estimated via linear regression from these steady-state values. The proposed approach has two practical features: (i) estimated static gains can be verified in a convincing way, because the validness of extracted steady-state values is confirmed by visualizing data segments in steady-state conditions, and the accuracy of estimated static gains is verified by comparing the extracted steady-state values and their estimates; (ii) the proposed approach is simple to understand and implement in practice, since it only involves a linear equation between steady-state values and static gains, as well as a basic technique of linear regression. Numerical simulation and industrial application demonstrate the effectiveness of the proposed approach.

Rapid maxillary expansion treatment increases mid-facial depth in early mixed dentition.

Objective: To evaluate the effects of rapid maxillary expansion (RME) on mid-facial depth in early mixed dentition and to investigate the relationship between change in mid-facial depth and maxillary sinus and nasal cavity. Methods: A total of 35 patients with mixed dentition treated with a Haas expander were included in this retrospective study. All patients underwent a cone-beam computed tomography scan before and after rapid maxillary expansion. The Wilcoxon signed-rank test was performed to evaluate the changes in maxillary width, facial depth, maxillary sinus, and nasal cavity volume before and after expansion. Multiple linear regression analysis was applied to evaluate the correlations among them. Results: The hard and soft tissue facial depth in the middle third increased significantly (P < 0.001). The gain on the outer sagittal plane (1.04-1.52 mm) was slightly bigger than that on the inner sagittal plane (0.91-1.30 mm). Maxillary width and nasal cavity width increased 3.42 ± 0.93 mm (P < 0.001) and 2.25 ± 0.77 mm (P < 0.001), respectively, after treatment. A gain was also achieved in both nasal cavity volume (2,236.15 mm3, P < 0.001) and maxillary sinus volume (1,227.33 mm3, P < 0.001). Multiple linear regression analysis showed that with the increase in maxillary sinus volume, the facial depth increased as well (B = 0.455-0.683, P < 0.05). Also, statistically significant correlations were found between nasal width and nasal cavity volume (B = 0.384, P < 0.05). Conclusion: The depth of the middle third face increased significantly. The facial depth increase was related to the enlargement of maxillary sinus volume, while the nasal cavity volume gain was related to the nasal width increase. This indicated that RME might enhance the fullness of the mid-face and facilitate the patency of nose breathing.

[Developmental characteristics of biological soil crusts and their effects on soil water infiltration on karst slope]. / å–€æ–¯ç‰¹å¡é¢ç”Ÿç‰©ç»“çš®å‘è‚²ç‰¹å¾åŠå ¶å¯¹åœŸå£¤æ°´åˆ†å ¥æ¸—çš„å½±å“.

Biological soil crusts (BSCs), as a pioneer for vegetation restoration and crucial component of surface landscape, greatly affect land surface process. To explore the development of BSCs and its effects on soil water infiltration in karst region, we investigated the development of BSCs and analyzed the infiltration processes with different BSCs coverages (0, 28%, 40%, 70%, 97%) and rainfall intensities (42 and 132 mm·h-1) in simulating rainfall experiments on a typical karst slope. The results showed that there were significant differences in the development of BSCs for different land use types, whereas the spatial variation of BSCs development on the slope was not obvious under the same land use type. Compared to the bare plot, the presence of BSCs significantly increased surface roughness, the initial runoff generation time, and soil water infiltration. In the cases of light (42 mm·h-1) and intensive (132 mm·h-1) rainfall, the initial infiltration rate of BSCs covered plots were 1.7-1.9 times and 1.2-1.9 times as that of bare plot, while the average infiltration rate in BSCs covered plots were 2.5-3.0 times and 1.4-3.3 times as that of bare plot, respectively. The BSCs coverage was significantly positively correlated with the initial runoff production time. The critical values of facilitating infiltration of BSCs coverage were between 65% and 70% under the test rainfall intensities. For heavy rainfall events, the inhibiting effects of BSCs on surface runoff were weakened. Horton model was the most reliable one for describing the infiltration process on karst slope with BSCs, followed by Kostiakov model and Philip model. In conclusion, the spatial variability of BSCs development on the karst slope was higher. The presence of BSCs had a significant effect on soil permeability in karst region.

Chronic cereulide exposure causes intestinal inflammation and gut microbiota dysbiosis in mice.

Known as a cause of food poisoning, Bacillus cereus (B. cereus) is widespread in nature. Cereulide, the heat-stable and acid-resistant emetic toxin which is produced by some B. cereus strains, is often associated with foodborne outbreaks, and causes acute emetic toxicity at high dosage exposure. However, the toxicological effect and underlying mechanism caused by chronic low-dose cereulide exposure require to be further addressed. In the study, based on mouse model, cereulide exposure (50 µg/kg body weight) for 28 days induced intestinal inflammation, gut microbiota dysbiosis and food intake reduction. According to the cell models, low dose cereulide exposure disrupted the intestinal barrier function and caused intestinal inflammation, which were resulted from endoplasmic reticulum (ER) stress IRE1/XBP1/CHOP pathway activation to induce cell apoptosis and inflammatory cytokines production. For gut microbiota, cereulide decreased the abundances of Lactobacillus and Oscillospira. Furthermore, cereulide disordered the metabolisms of gut microbiota, which exhibited the inhibitions of butyrate and tryptophan. Interestingly, cereulide exposure also inhibited the tryptophan hydroxylase to produce the serotonin in the gut and brain, which might lead to depression-like food intake reduction. Butyrate supplementation (100 mg/kg body weight) significantly reduced intestinal inflammation and serotonin biosynthesis suppression caused by cereulide in mice. In conclusion, chronic cereulide exposure induced ER stress to cause intestinal inflammation, gut microbiota dysbiosis and serotonin biosynthesis suppression. IRE1 could be the therapeutic target and butyrate supplementation is the potential prevention strategy.

Enzymatic characteristics of a recombinant protease (rPepD) from Aspergillus niger expressed in Pichia pastoris.

The Aspergillus niger AS3.350 protease gene (pepD) was successfully cloned and expressed in Pichia pastoris KM71. The rPepD activity was 331.5 U/ml, and the optimum temperature and pH were 45 °C and 8-9 respectively. In addition, enzyme activity was significantly inhibited by PMSF, EDTA, Mg2+, Fe2+ and Zn2+ ions, and stimulated by Ca2+ which selectively bound to the T302 and D323 residues. Mutation in either or both of the residues inhibited rPepD expression, indicating that binding to Ca2+ is necessary for PepD expression and activity. The rPepD showed a wide substrate range, and was particularly selective to those with hydrophobic amino acids. The degree of rPepD-mediated hydrolysis of soy protein isolate, corn flour and gluten meal were 8.7%, 38.1% and 33.6% respectively, which was higher than that by Alcalase, indicating that rPepD has potential applications in the food processing industry.

[Study on root canal variation of maxillary premolar and its relationship to maxillary sinus by cone-beam CT].

PURPOSE: To investigate the anatomic morphology of root and root canal system of maxillary premolars by using cone-beam computer tomography (CBCT), in order to provide imaging basis for clinical treatment. METHODS: CB CT images of 720 patients (aged from 18 to 67 years) were included. They were divided into 5 groups according to their ages：18-28，29-38，39-48，49-58 and＞58 years old . The number of roots and root canals, root canal configuration, the distance between two orifices,root canal curvature,distance from apex to maxillary sinus,symmetry of the bilateral teeth and its relationship to age changes were analyzed statistically using SPSS21.0 software package. RESULTS: Double root canal of the first maxillary premolar accounted the most (89.72%), and type IV was the frequent type (57.78%) . The incidence of single root canal in the second maxillary premolar (53.06%) was slightly higher than double root canal (46.94%). Root canal type was mainly type I (53.06%). There was symmetrical distribution in the bilateral root and root canals of maxillary premolars. The detection rate of the single root canal was changed with age, and the distance between the two orifice was closely related to the root morphology. The detection rate of root curvature in maxillary first and second premolar was 32.53% and 21.50% in buccolingual direction. There was a certain proportion of S-type complex root canal.16.69% of the maxillary second premolar and maxillary sinus were closely related (d≤0.05 mm). CONCLUSIONS: The anatomical structure of root and root canal is complicated .The prevalence of the bilateral teeth presents symmetry and age-related changes.The curvature of root canal is complex, and the roots are closely related to maxillary sinus.

Changes in mycelia growth, sporulation, and virulence of Phytophthora capsici when challenged by heavy metals (Cu2+, Cr2+ and Hg2+) under acid pH stress.

Phytophthora capsici, an economically devastating oomycete pathogen, causes devastating disease epidemics on a wide range of vegetable plants and pose a grave threat to global vegetables production. Heavy metals and acid pH are newly co-occurring stresses to soil micro-organisms, but what can be expected for mycelia growth and virulence and how they injure the oomycetes (especially P. capsici) remains unknown. Here, the effects of different heavy metals (Cu2+, Cr2+, and Hg2+) on mycelia growth and virulence were investigated at different pHs (4.0 vs. 7.0) and the plausible molecular and physiological mechanisms were analyzed. In the present study, we compared the effective inhibition of different heavy metals (Cu2+, Cr2+, and Hg2+) and acid pH on a previously genome sequenced P. capsici virulent strain LT1534. Both stress factors independently affected its mycelia growth and sporulation. Next, we investigated whether ROS participated in the pH-inhibited mycelial growth, finding that the ROS scavenger, catalase (CAT), significantly inhibited the acid pH-induced ROS in mycelia. Additionally, because MAPK specially transmits different stress responsive signals in environment into cells, we employed CAT and a p38-MAPK pathway inhibitor to investigate ROS and p38-MAPK roles in heavy metal-inhibited mycelia growth at different pHs (4.0 vs. 7.0), finding that they significantly inhibited growth. Furthermore, ROS and p38-MAPK influenced the heavy metal-induced TBARS content, total antioxidant capacity (TAC), and CAT activity at different pHs, and also reduced the expression of infection-related laccases (PcLAC2) and an effector-related protein (PcNLP14). We propose that acid pH stress accelerates how heavy metals inhibit mycelium growth, sporulation, and virulence change in P. capsici, and posit that ROS and p38-MAPK function to regulate the molecular and physiological mechanisms underlying this toxicity. Although these stresses induce molecular and physiological challenges to oomycetes, much remains to be known the mechanisms dedicated to resolve these environmental stresses.