Obesity induced caveolin-1 impairs osteogenesis via activating mitophagy and inhibiting Sirt1 signaling.

Obesity has become a major global health problem and the effect on bone formation has received increasing attention. However, the interaction between obesity and bone metabolism is complex and still not fully understood. Here, we show that caveolin-1 (Cav1), a membrane scaffold protein involved in regulating a variety of cellular processes, plays a key regulatory role as a bridge connecting obesity and bone metabolism. High-fat diet (HFD)-induced obese C57BL/6J mouse displayed a significant increase in Cav1 expression and lower osteogenic activity; In vitro treatment of osteoblastic MC3T3-E1 cells with 1 mM free fatty acids (FFA) significantly promoted Cav1 expression and PINK1/Parkin regulated mitophagy, but inhibited the expression of osteogenic marker genes. Conversely, reduced expression of the Cav1 gene prevented these effects. Both endogenous oxidative stress and Sirt1 pathway were also significantly reduced after Cav1 knockdown in FFA-treated cells. Finally, Cav1-Sirt1 docking and co-immunoprecipitation results showed that Cav1 interacted with Sirt1 and FFA enhanced the interaction. Taken together, these results suggest that obesity impairs bone development and formation through up-regulation of the Cav1 gene, which lead to inhibition of Sirt1/FOXO1 and Sirt1/PGC-1α signaling pathways through interacting with Sirt1 molecule, and an increase of mitophagy level.

Influence of impact velocity and impact attack angle of bullets on damage of human tissue surrogate -- ballistic gelatin.

PURPOSE: Terminal performance of a bullet in human body is critical for the treatment of gunshot injury and optimization of bullet design. The effects of the impact velocity (v0) and the impact attack angle (δ0) of the bullet on its terminal performance was investigated, using a new evaluation method (called expansion method) based on the expansion of cracks and the permanent cavity wall in ballistic gelatin. METHODS: Ballistic gelatin was used to simulate human body. The 7.62 mm × 39 mm rifle bullets with different v0 (600-760 m/s) and δ0 (0°-6°) were fired into the gelatin blocks. The gelatin block was cut into slices of about 20 mm thickness. The cracks and the permanent cavity on each slice were obtained manually. The damaged gelatin was determined using two methods: expanding the permanent cavity but ignoring the cracks, and expanding both the permanent cavity and the cracks. The relations between the damaged gelatin and v0 and δ0 were obtained using linear fitting method. RESULTS: According to the distribution of the damaged gelatin along the penetration depth, the damaged gelatin block could be divided into two parts: the less damaged part and the severely damaged part. The length of the less damaged part depends mostly on δ0; while the average damaged area of this part depends on both δ0 as well as v0. The cracks contributed significantly to the total volume of damaged gelatin, particularly when the expansion was larger than 1.9 mm. The total damaged gelatin increases with v0, δ0 and the expansion extent. The average length of equivalent cracks grew with v0 and δ0 when considering the cracks, and decreased with v0 when ignoring the cracks. CONCLUSION: The expansion method is suitable to investigate the influence of different factors of bullets on their terminal performance. The characteristics of the damaged gelatin have a linear relationship with the initial attack angle (δ0) and the initial velocity (v0) of the bullet.

Mechanical response of porcine hind leg muscles under dynamic tensile loading.

A modified split Hopkinson tension bar (SHTB) apparatus was used to investigate the dynamic tensile mechanical response of porcine muscles. A hollow aluminum alloy transmission bar and a semiconductor strain gauge were used to enhance the weak signal from porcine muscles. A ring-shaped copper pulse shaper was used to achieve stress equilibrium and constant approximate strain rates in the specimens. The thin muscle specimen, fixed by 3D-printed clamps, was warped around the bar ends to minimize the radial inertial effect during tensile loading. The quasi-static tests at strain rates of 0.1 s∧-1 were also conducted on a universal material testing machine to investigate the strain rate dependence. The true stress-strain curves of porcine muscle tissues along the fiber direction were determined at approximate strain rates of 800 s∧-1, 2000 s∧-1, and 3000 s∧-1. The experimental results show that the porcine muscle exhibits nonlinear, rate-sensitive, and orthotropic behavior. The Mooney-Rivlin model with two material constants was sufficient to represent the tensile response of porcine muscles at each strain rate. The rate-dependent Fields-Backofen model can describe the high strain rate response of the porcine muscles.

Photodegradation of Cationic and Anioic Dyes by pH-Dependent Dispersion of Amphoteric g-C3N4 Nanosheets.

g-C3N4 nanosheets (NSs) were prepared via H2SO4 exfoliation from the bulky g-C3N4 and the photocatalytic (PC) activities were investigated comprehensively using Rodamine B (RhB) and Chromotrope 2R (Ch2R) as candidate pollutants. The results showed that the pH value have important functions in the improvement of photodegradation performance of C3N4 NSs. RhB as cationic dye could be photodegraded more efficiently under acidic conditions while Ch2R as anionic dye was degraded easily in pH ≥ 11 solution. In particular, the Ch2R could be degraded completely within only 30 min in pH = 11 solution. It might be because the amphoteric C3N4 NSs surface with carboxyl and amino groups possessed negative and positive charges in alkaline and acidic conditions, respectively. These results presumably provided a new idea to enhance the pH-dependent photodegradation activity and degrade different types of pollutants selectively by adjusting the pH of amphoteric nanocatalyts.

[Fire needling on dysphagia due to pseudobulbar palsy after stroke: a randomized controlled trial].

OBJECTIVE: To observe the clinical effect of fire needling on dysphagia due to pseudobulbar paralysis after stroke and to compare the difference in clinical effect between fire needling and swallowing function rehabilitation training. METHODS: A total of 76 patients with dysphagia due to pseudobulbar paralysis after stroke were randomly divided into an observation group and a control group, 38 cases in each group (1 case dropped out in the control group). The both groups were based on conventional western medication treatment. Fire needle pricking was exerted at Lianquan (CV 23), Fengchi (GB 20), Wangu (GB 12), Shuigou (GV 26), Neiguan (PC 6) and Zusanli (ST 36) without needle retaining every other day in the observation group. The control group was treated with the swallowing function rehabilitation training. In both groups, treatment for 2 weeks was as one course and 2 courses of treatment with 2-day interval were required. After treatment, swallowing scores of Fujishima Ichiro and swallow quality of life questionnaire (SWAL-QOL) scores were observed in both groups, and the clinical effect was compared. Follow-up of swallowing scores of Fujishima Ichiro in 4 weeks after treatment was completed to evaluate the clinical effect. RESULTS: The clinical effective rates after treatment and follow-up were 92.1% (35/38) and 94.7% (36/38) in the observation group, higher than 75.7% (28/37) and 83.8% (31/37) in the control group (P<0.05). After treatment, the swallowing scores of Fujishima Ichiro and SWAL-QOL scores were increased in the two groups (P<0.05), and those in the observation group were higher than the control group (P<0.05). The swallowing scores of Fujishima Ichiro were increased during follow-up in the two groups (P<0.05). CONCLUSION: Fire needling has a better effect than conventional rehabilitation training in the treatment of dysphagia due to pseudobulbar paralysis after stroke, which can obviously improve the swallowing function and quality of life in patients with dysphagia.

Conjugated Polythiophene for Rapid, Simple, and High-Throughput Screening of Antimicrobial Photosensitizers.

The cationic conjugated poly[3-(3'-N,N,N-triethylamino-1'-propyloxy)-4-methyl-2,5-thiophene hydrochloride] (PMNT) has been developed for high-throughput screening of photodynamic antimicrobial chemotherapy photosensitizers (PSs). The bacterial number can be detected quantitatively by PMNT via various fluorescence quenching efficiencies. The photosensitized inactivation of bacteria is not efficient with ineffective PSs, and thus the bacteria grow exponentially and can be coated tightly by PMNT through electrostatic and hydrophobic interactions, resulting in aggregates and fluorescence quenching of PMNT, whereas, conversely, effective PSs lead to original and strong fluorescence of PMNT. This new platform of high-throughput screening is promising for discovering new PSs.

Ca2+-controlled assembly for visualized detection of conformation changes of calmodulin.

A new strategy has been designed for visualized detection of the conformation changes of calmodulin bound to target peptide (CaM-M13) based on the conformation sensitive property of a water-soluble conjugated polythiophene derivative (PMNT) and the electrostatic interactions of PMNT/CaM-M13. Interestingly, the direct visualized PMNT color changes under UV irradiation and the turbidity changes of samples in aqueous medium can be applied to detect the conformation changes as well as the controllable assembly of PMNT/CaM-M13 with Ca(2+) in aqueous medium. Because of the specific binding of Ca(2+), the assembly of PMNT/CaM-M13 can be applied to sense calcium as well.