PL-010 Chronic mild stress improves glucose homeostasis via myonectin-mediated suppression of sympathetic activity in high-fat diet-fed mice

Objective Recent studies suggest that chronic stress exposure can ameliorate the progression of diet-induced prediabetic disease, by inhibiting an increase in weight gain, caloric intake and efficiency and insulin resistance. To determine the underlying mechanism by which chronic stress improves the progression of type 2 diabetes, we developed a model of chronic mild stress in high-fat diet(HFD)-fed mice which are resistant to obesity and exhibit a healthy-like metabolic phenotype. Methods High-fat diet (HFD): 45% kcal derived from fat (Research Diets, Inc.).Mice experienced one stressor during the day and a different stressor during the night. Stressors were randomly chosen from the following list : cage tilt on a 45° angle for 1 to 16 h; food deprivation for 12 to 16 h; white noise for 1 to 16 h; strobe light illumination for 1 to 16 h; crowded housing; light cycle (continuous illumination) for 24 to 36 h; dark cycle (continuous darkness) for 24 to 36 h; water deprivation for 12 to 16 h; damp bedding (200 ml water poured into sawdust bedding) for 12 to 16 h.Recombinant adeno-associated virus (AAV): AAV9 vectors encoding myonectin under the control of the ubiquitous CMV promoter (AAV9-CMV-Vip) or an equal dose of the AAV9-CMV-null vector were delivered to C57BL/6 mice by the tail vein. Mice were deprived of food for 16 h and then subjected to test 7 days after AAV injection. Results Chronic stress improved glucose intolerance and sympathetic overactivity in HFD-fed mice. Chronic stress attenuated epinephrine(EPI)-stimulated glycerol release into blood in vivo and accelerated glycerol release from white adipose tissue followed by in vitro incubation with EPI. Chronic stress reduced plasma triglyceride but increased the levels of plasma insulin and myonectin. We further found that adeno-associated virus 9 (AAV9)-mediated myonectin overexpression improved glucose homeostasis and reduced epinephrine sensitivity. Myonectin overexpression reduced plasma norepinephrine, EPI and leptin levels, and increased insulin sensitivity in brown and white adipose tissue. Intense sympathetic activity with high-intensity running inhibited myonectin expression in skeletal muscle, whereas medium and low-intensity exercise running increased myonectin expression. Conclusions These findings suggest that chronic mild stress can improve glucose homeostasis via myonectin-mediated suppression of sympathetic activity in high-fat diet-fed mice

Tai Chi Chuan and Baduanjin Mind-Body Training Changes Resting-State Low-Frequency Fluctuations in the Frontal Lobe of Older Adults: A Resting-State fMRI Study

Age-related cognitive decline is a significant public health concern. Recently, non-pharmacological methods, such as physical activity and mental training practices, have emerged as promising low-cost methods to slow the progression of age-related memory decline. In this study, we investigated if Tai Chi Chuan (TCC) and Baduanjin modulated the fractional amplitude of low-frequency fluctuations (fALFF) in different frequency bands (low-frequency: 0.01–0.08 Hz; slow-5: 0.01–0.027 Hz; slow-4: 0.027–0.073 Hz) and improved memory function. Older adults were recruited for the randomized study. Participants in the TCC and Baduanjin groups received 12 weeks of training (1 h/day for 5 days/week). Participants in the control group received basic health education. Each subject participated in memory tests and fMRI scans at the beginning and end of the experiment. We found that compared to the control group: (1) TCC and Baduanjin groups demonstrated significant improvements in memory function; (2) TCC increased fALFF in the dorsolateral prefrontal cortex (DLPFC) in the slow-5 and low-frequency bands; and (3) Baduanjin increased fALFF in the medial PFC in the slow-5 and low-frequency bands. This increase was positively associated with memory function improvement in the slow-5 and low-frequency bands across the TCC and Baduanjin groups. Our results suggest that TCC and Baduanjin may work through different brain mechanisms to prevent memory decline due to aging

The Effects of Different Carbon Sources on the Production Environment and Breeding Parameters of Litopenaeus vannamei

This study investigated the effect of different carbon sources on water quality, ammonia removal pathways, the bacterial community, and the production of Litopenaeus vannamei in outdoor culture tanks. Three systems were established: a clear water system (CW) and biofloc technology (BFT) systems with added molasses (M-BF) or poly (3-hydroxybutyric acid-co-3-hydrovaleric acid) (PHBV) (P-BF). The average pH, total alkalinity, total organic carbon, biofloc volume, chlorophyll a, nitrite, nitrate, total nitrogen, and nitrification rate were significantly different among the treatments. Microbial composition varied and different dominant taxa were identified in the treatments by linear discriminant analysis effect size. Redundancy analysis indicated that the water quality parameters affected the distribution of the microbial community. Moreover, the genus Leucothrix was closely related to the M-BF treatment. Chemoheterotrophy and aerobic chemoheterotrophy were the most abundant functions in all treatments. A comparison of functions using BugBase indicated that the relative abundance of several functions such as biofilm formation, stress tolerance and functions related to anaerobic processes increased in the M-BF treatment. The specific growth rate, growth rate, and survival rate of shrimp were significantly higher in the P-BF system than in the CW system and the feed conversion ratio in the BFT treatments was significantly lower than that in the CW system. Overall, adding carbon sources affected water quality, microbial community, and shrimp performance. The results show that PHBV is a good alternative to carbon sources

Wear mechanism and evolution of tribofilm of ceramic on steel pairs under ester oil lubrication in wide temperature range

The ceramic-steel-pentaerythritol ester system has a broad application prospect under high temperature conditions, which are respectively in the fields of aviation, aerospace and advanced equipment manufacturing. However, a comprehensive understanding of the friction and wear mechanisms of this system across a broad temperature range remains elusive. The tribological properties of the system at 25–475 °C were studied. With the increase of temperature, the evolution of the tribofilm follows the sequence: discontinuous tribofilm → uniform tribofilm → tribofilm removal. At 200–300 °C, an approximately 100 nm thick amorphous PxOy compound tribofilm is formed, and its nanohardness and modulus are reduced by 81.33 % and 54.02 %, respectively, compared with base steel. The tribofilm effectively reduces shear resistance by blocking friction pair contact. When the temperature exceeds 300 °C, it will lead to high-temperature coking, which adversely affects the lubrication performance. It is worth noting that the system can endure short-term service at a maximum temperature of 475 °C. Therefore, this research can help achieve continuous, stable operation of high-temperature resistant systems, as well as short-term use under extreme conditions encountered by complex equipment

Effect of Thickness of HA-Coating on Microporous Silk Scaffolds Using Alternate Soaking Technology

Hydroxyapatite (HA) can be coated on various materials surface and has the function of osteogenicity. Microporous silk scaffold has excellent biocompatibility. In this study, alternate soaking technology was used to coat HA on microporous silk scaffolds. However, the cell proliferation was found to decrease with the increasing thickness (cycles of soaking) of HA-coating. This study aims to determine the best thickness (cycles of soaking) of HA-coating on microporous silk scaffolds. The SEM observation showed that group with one cycle of alternate soaking (1C-HA) has the most optimal porosity like non-HA-modified microporous silk scaffolds. The proliferation of osteoblasts has no significant difference between noncoated HA (N-HA) and 1C-HA groups, which are both significantly higher than those in two cycles of soaking (2C-HA) and three cycles of soaking (3C-HA) groups. The transcription levels of specific genes (runx2 and osteonectin) in osteoblasts of 1C-HA group were significantly higher than those of N-HA group. Moreover, the levels showed no significant difference among 1C-HA, 2C-HA, and 3C-HA groups. In conclusion, microporous silk scaffold with 1 cycle of HA-coating can combine the biocompatibility of silk and osteogenicity of HA

Tai Chi Chuan and Baduanjin practice modulates functional connectivity of the cognitive control network in older adults

Cognitive impairment is one of the most common problem saffecting older adults. In this study, we investigated whether Tai Chi Chuan and Baduanjin practice can modulate mental control functionand the resting state functional connectivity (rsFC) of the cognitive control network in older adults. Participants in the two exercise groups practiced either Tai Chi Chuan or Baduanjin for 12 weeks, and those in the control group received basic health education. Memory tests and fMRI scans were conducted at baseline and at the end of the study. Seed-based (bilateral dorsolateral prefrontal cortex, DLPFC) rsFC analysis was performed. We found that compared to the controls, 1) both Tai Chi Chuan and Baduanjin groups demonstrated significant improvements in mental control function; 2) the Tai Chi Chuan group showed a significant decrease in rsFC between the DLPFC and the left superior frontal gyrus (SFG) and anterior cingulate cortex; and 3) the Baduanjin group showed a significant decrease in rsFC between the DLPFC and the left putamen and insula. Mental control improvement was negatively associated with rsFC DLPFC-putamen changes across all subjects. These findings demonstrate the potential of Tai Chi Chuan and Baduanjin exercises in preventing cognitive decline

Genomic Variation and Host Interaction among <i>Pseudomonas syringae</i> pv. <i>actinidiae</i> Strains in <i>Actinidia chinensis</i> ‘Hongyang’

Kiwifruit bacterial canker is a recent epidemic disease caused by Pseudomonas syringae pv. actinidiae (Psa), which has undergone worldwide expansion in a short time and resulted in significant economic losses. ‘Hongyang’ (Actinidia chinensis), a widely grown cultivar because of its health-beneficial nutrients and appreciated red-centered inner pericarp, is highly sensitive to Psa. In this work, ten Psa strains were isolated from ‘Hongyang’ and sequenced for genome analysis. The results indicated divergences in pathogenicity and pathogenic-related genes among the Psa strains. Significantly, the interruption at the 596 bp of HrpR in two low-pathogenicity strains reemphasized this gene, expressing a transcriptional regulator for the effector secretion system, as an important pathogenicity-associated locus of Psa. The transcriptome analysis of ‘Hongyang’ infected with different Psa strains was performed by RNA-seq of stem tissues locally (at the inoculation site) and systemically. Psa infection re-programmed the host genes expression, and the susceptibility to Psa might be attributed to the down-regulation of several genes involved in plant-pathogen interactions, especially calcium signaling transduction, as well as fatty acid elongation. This suppression was found in both low- and high-pathogenicity Psa inoculated tissues, but the effect was stronger with more virulent strains. Taken together, the divergences of P. syringae pv. actinidiae in pathogenicity, genome, and resulting transcriptomic response of A. chinensis provide insights into unraveling the molecular mechanism of Psa-kiwifruit interactions and resistance improvement in the kiwifruit crop

Boosting Cycling Stability of Polymer Sodium Battery by “Rigid-Flexible” Coupled Interfacial Stress Modulation

The discontinuous interfacial contact of solid-state polymer metal batteries is due to the stress changes in the electrode structure during cycling, resulting in poor ion transport. Herein, a rigid-flexible coupled interface stress modulation strategy is developed to solve the above issues, which is to design a rigid cathode with enhanced solid-solution behavior to guide the uniform distribution of ions and electric field. Meanwhile, the polymer components are optimized to build an organic-inorganic blended flexible interfacial film to relieve the change of interfacial stress and ensure rapid ion transmission. The fabricated battery comprising a Co-modulated P2-type layered cathode (Na0.67Mn2/3Co1/3O2) and a high ion conductive polymer could deliver good cycling stability without distinct capacity fading (72.8 mAh g-1 over 350 cycles at 1 C), outperforming those without Co modulation or interfacial film construction. This work demonstrates a promising rigid-flexible coupled interfacial stress modulation strategy for polymer-metal batteries with excellent cycling stability