A microfluidic-based gut-on-a-chip model containing the gut microbiota of patients with depression reveals physiological characteristics similar to depression.

The diverse commensal microbiome of the human intestine has been considered to play a central role in depression. However, no host-microbiota co-culture system has been developed for depression, which hinders the controlled study of the interaction between depression and gut microbiota. We designed and manufactured a microfluidic-based gut-on-a-chip model containing the gut microbiota of patients with depression (depression-on-gut-chip, DoGC), which enables the extended co-culture of viable aerobic human intestinal epithelial cells and anaerobic gut microbiota, and allows the direct study of interactions between human gut microbiota and depression. We introduced representative gut microbiota from individuals with depression into our constructed DoGC model, successfully recapitulating the gut microbiota structure of depressed patients. This further led to the manifestation of physiological characteristics resembling depression, such as reduced gut barrier function, chronic low-grade inflammatory responses and decreased neurotransmitter 5-HT levels. Metabolome analysis of substances in the DoGC revealed a significant increase in lipopolysaccharides and tyrosine, while hyodeoxycholic acid, L-proline and L-threonine were significantly reduced, indicating the occurrence of depression. The proposed DoGC can serve as an effective platform for studying the gut microbiota of patients with depression, providing important cues for their roles in the pathology of this condition and acting as a powerful tool for personalized medicine.

Long-term artificial/natural daytime light affects mood, melatonin, corticosterone, and gut microbiota in rats.

The desynchronization of circadian rhythms affected by light may induce physiological and psychological disequilibrium. We aimed to elucidate changes of growth, depression-anxiety like behaviors, melatonin and corticosterone (CORT) secretion, and gut microbiota in rats influenced by long-term light inputs. Thirty male Sprague-Dawley rats were exposed to a 16/8 h light/dark regime for 8 weeks. The light period was set to 13 h of daylight with artificial light (AL group, n = 10), or with natural light (NL group, n = 10), or with mixed artificial-natural light (ANL group, n = 10), and 3 h of artificial night light after sunset. The obtained findings indicated that the highest weight gain and food efficiency were observed in the AL group and the lowest in NL group. In the behavioral tests, the NL and ANL groups showed lower anxiety level than AL group, and ANL groups showed lower depression level than AL group. The NL and ANL groups had delayed acrophases and maintained higher concentrations of melatonin compared to AL group. The circadian rhythm of CORT was only found in ANL group. At the phylum level, the mixed light contributed to a lower abundance of Bacteroidetes. The genus level results recommend a synergistic effect of artificial light and natural light on Lactobacillus abundance and an antagonistic effect on the Lachnospiraceae_NK4A136_group abundance. The study indicated that the mixture of artificial and natural light as well as the alignment of the proportions had beneficial influences on depression-anxiety-like levels, melatonin and corticosterone secretion, and the composition of the gut microbiota. KEY POINTS: • The mixed light can reduce the depression-anxiety level • The mixed light can maintain the secretion rhythm of melatonin and CORT • The mixed light can increase Lactobacillus and decrease Lachnospiraceae_NK4A136_group.

Perforating ocular injury caused by acupuncture: A case report.

Acpuncture as a branch of traditional Chinese medicine is popular in China. It can regulate the running of meridian qi to stimulate the ocular nerve activity and increase blood supply. Periocular acupuncture treatment is very frequent, but it can lead to safety hazards that cannot be ignored. For instance, ocular trauma may develop if done improperly, resulting in impaired vision and even blindness. We report a rare case of perforating ocular injury caused by acupuncture.

Process Modelling and Simulation of Key Volatile Compounds of Maillard Reaction Products Derived from Beef Tallow Residue Hydrolysate Based on Proxy Models.

The hydrolysis time is directly related to the flavor of the Maillard reaction, but existing proxy models cannot simulate and model the variation curves of vital volatile components. This study developed a predictive model for modelling and simulating key volatile compounds of Maillard reaction products (MRPs) derived from beef tallow residue hydrolysate. Results showed the degree of hydrolysis increased with hydrolysis time, and the most significant improvement in the roast flavor and overall acceptance was when hydrolyzing 4 h. Based on flavor dilution value and the relative odor activity value, nine key volatile components were identified, and 2-ethyl-3,5-dimethylpyrazine with roast flavor was the highest. Compared with Polynomial Curve Fitting (PCF) and Cubic Spline Interpolation (CSI), key volatile compounds of MRPs could be better modeled and simulated by the Curve Prediction Model (CPM). All results suggested that CPM could predict the changes in key volatile components produced by MRPs.

Prediction of flavor of Maillard reaction product of beef tallow residue based on artificial neural network.

The beef flavor of beef tallow residue was improved by enzymatic hydrolysis followed by the Maillard reaction, and the flavor could be predicted using an artificial neural network. Five beef tallow residue hydrolysates were prepared using different enzymes. The Flavourzyme and Papain (FP) hydrolysate had low molecular weight peptides and high degree of hydrolysis and free amino acid content. We identified 49 main compounds, including aldehydes, pyrazines, and furan. Furan and pyrazine were the dominant volatile compounds in the five beef tallow residue-derived Maillard reaction products (MRPs), and their profiles and levels in the FP MRPs were high. The FP MRPs had the best sensory characteristics. The artificial neural network analysis revealed that the multiple input single output model had a better performance than the single input single output model, and the prediction accuracy was>90%, indicating that the MRPs sensory evaluation scores could be accurately predicted.

Spatiotemporal-resolved protein networks profiling with photoactivation dependent proximity labeling.

Enzymatic-based proximity labeling approaches based on activated esters or phenoxy radicals have been widely used for mapping subcellular proteome and protein interactors in living cells. However, activated esters are poorly reactive which leads to a wide labeling radius and phenoxy radicals generated by peroxide treatment may disturb redox-sensitive pathways. Herein, we report a photoactivation-dependent proximity labeling (PDPL) method designed by genetically attaching photosensitizer protein miniSOG to a protein of interest. Triggered by blue light and tunned by irradiation time, singlet oxygen is generated, thereafter enabling spatiotemporally-resolved aniline probe labeling of histidine residues. We demonstrate its high-fidelity through mapping of organelle-specific proteomes. Side-by-side comparison of PDPL with TurboID reveals more specific and deeper proteomic coverage by PDPL. We further apply PDPL to the disease-related transcriptional coactivator BRD4 and E3 ligase Parkin, and discover previously unknown interactors. Through over-expression screening, two unreported substrates Ssu72 and SNW1 are identified for Parkin, whose degradation processes are mediated by the ubiquitination-proteosome pathway.

Fermentation optimization and amylase activity of endophytic Bacillus velezensis D1 isolated from corn seeds.

AIMS: To acquire quality amylase adopted in practical applications, endophytic bacteria were identified as Bacillus velezensis strain D1 which was isolated from corn seeds. The fermentation conditions and amylase properties of the strain were investigated. METHODS AND RESULTS: The strain D1 was identified via morphological, physiological and 16S rDNA phylogenetic analysis. The fermentation conditions of secreting amylase were optimized by single-factor and orthogonal experiments. The α-amylase gene was expressed in E. coli and purified by means of immobilized metal ion affinity chromatography (IMAC), upon which the enzyme activity of purified recombinant α-amylase was determined. The results outlined that (1) The strain D1 was identified as Bacillus velezensis. (2) The optimized fermentation conditions for maximum amylase yields included 44°C for 48 h at pH 7.5. (3) The enzyme had an optimal reaction temperature of 60°C with the highest activity at 50°C and tolerance to 4-h incubation at 70°C. (4) The enzyme was strong acid resistant and tolerated at pH 5.0-6.0 while the optimal pH was 8.0. (5) Besides, the amylase activity was elevated by the presence of Ca2+ and Cu2+ . (6) The activity of purified recombinant amylase was 20.59 U/ml under optimal conditions, nearly seven times that of crude amylase preparations. CONCLUSIONS: The amylase produced by Bacillus velezensis D1 is strongly tolerant towards acid and high temperatures. SIGNIFICANCE AND IMPACT OF THE STUDY: Amylases with thermophilic and acid-resistant characteristics are useful for a wide range of applications in food, brewing, textile, starch, paper and deterrent industries. The enzyme from Bacillus velezensis D1 can be effectively used in different areas of industries.

Constrained unsteady-state iris fast certification for lightweight training samples based on the scale change stable feature and multi-algorithm voting.

Aiming at the problem of fast certification for a constrained iris in the same category caused by the unstable iris features caused by the change of the iris acquisition environment and shooting status under lightweight training samples, a one-to-one fast certification algorithm for constrained unsteady-state iris based on the scale change stable feature and multi-algorithm voting is proposed. Scale change stable features are found by constructing an isometric differential Gaussian space, and a local binary pattern algorithm with extended statistics (ES-LBP), the Haar wavelet with over threshold detection and the Gabor filter algorithm with immune particle swarm optimization (IPSO) are used to represent the stable features as binary feature codes. Iris certification is performed by the Hamming distance. According to the certification results of three algorithms, the final result is obtained by multi-algorithm voting. Experiments with the JLU and CASIA iris libraries under the iris prerequisite conditions show that the correct recognition rate of this algorithm can reach a high level of 98% or more, indicating that this algorithm can improve the operation speed, accuracy and robustness of certification.

[Hemodynamic performance of newly developed composite stentless porcine aortic valve: in vitro testing and in vivo experiment with sheep].

OBJECTIVE: To investigate the effects of a newly developed composite stentless porcine aortic valve constructed from noncoronary leaflets of three porcine aortic valves. METHODS: Fresh porcine hearts with ascending aorta were obtained from a slaughterhouse. The porcine aortic roots with ascending aorta and anterior leaflet of mitral valve and partial ventricular septum were dissected out and were pressurized to maintain their natural anatomical shapes with the leaflets floating freely at zero-pressure. Three noncoronary leaflets fixed in 0.6% glutaraldehyde were carefully matched for size and symmetry to construct a novel composite stentless porcine aortic valve. The lower margin and outside of the valve was covered with a piece of bovine pericardium. The novel stentless valves were tested in vitro pulsatile flow to detect the effective orifice area (EOA) and mean pressure difference (DeltaP) of the valve compared with the stented bovine pericardial bioprostheses of the same size. Sixteen male juvenile sheep underwent implantation of the novel valves in the supra-annular position in under cardio-pulmonary bypass. The intraoperative and postoperative echocardiography and pathological specimen were given to evaluate the hemodynamic performance and observed in the respects of a long-term survival, function of valve and pathological specimen. RESULTS: Since novel valves had the unfavorable muscle-based right coronary leaflet characteristic of porcine valve removed it had larger EOA. Pulsatile flow testing indicated that the EOA of the 3 novel valves was (3.47 +/- 0.15), (3.69 +/- 0.11), and (3.92 +/- 0.18) cm2 respectively, all significantly greater than those of the stented bovine pericardial bioprosthesis [(2.00 +/- 0.16), (2.21 +/- 0.26), and (2.37 +/- 0.42) cm2 respectively] at each integral simulated cardiac output between 3 - 6 L/min (all P < 0.05), while the DeltaP levels of the novel valves were (2.35 +/- 0.41), (3.10 +/- 0.20), and (3.56 +/- 0.16) mm Hg respectively, all significantly lower than those of the stented bovine pericardial bioprosthesis [(4.98 +/- 0.46), (6.82 +/- 1.27), and (8.40 +/- 1.83) mm Hg respectively, all P < 0.05]. Twelve of the sixteen sheep survived after operation. Five of them had lived for more than 90 days, 3 more than 180 days, and 2 more than 360 days. The intra-operative echocardiographic analyses showed low DeltaP [(3.90 +/- 0.78) mm Hg] and no regurgitation in all sheep. After 15 to 360 days, all valves performed excellently. The sheep were postoperatively sacrificed in 5 d, 15 d, 45 d, 90 d, 180 d, or 300 d respectively. Necropsy revealed the valves had a low to mild level of calcification, without periprosthetic leakage and overgrowth of fibrous tissue. CONCLUSION: The newly developed composite stentless porcine aortic valves show excellent hemodynamic performance with lower transvalvular pressure gradient and are relatively easy to implant.

[Crosslinking bovine pericardial bioprosthetic heart valves by phthalocyanine sensitized photooxidation reaction].

OBJECTIVE: To crosslink bovine pericardial valves by phthalocyanine sensitized photooxidation reaction. METHODS: Fresh bovine pericardial tissues were immersed in PBS solution containing 0.01% cupreous sulfonatophthalocyanine and exposed to a broad wavelength light source for 20-120 h. Using sodium dodecyl sulfate-polyarylamide gel electrophoresis (SDS-PAGE) to analyze the cross-linking extent of pericardial tissue. With the help of attenuated total reflection-fourier transform infrared (ATR-FTIR), explained the change of protein structure after photooxidation reaction. Differential scanning calorimetry (DSC) was used to measure the change of shrinkage temperature. Tissue water content experiment method was also used. RESULTS: Photooxidized tissue was resistant to extraction when it was compared with untreated tissue and had similar crosslinking extent over glutaraldehyde-treated tissue. The three dimension structure of collagen were changed but not seriously destroyed and the model of photooxidation reaction was validated. Phthalocyanine-treated tissue was much more flexible than glutaraldehyde-treated tissue. CONCLUSION: Bovine pericardial tissue can be successfully crosslinked by phthalocyanine-mediated photooxidation reaction.

[Using chemical methods to crosslink xenogeneic heart valves: the progress of bioprosthetic heart valves].

Glutaraldehyde clinically is the most commonly accepted crosslinking reagent for bioprosthetic valves preparation. Glutaraldehyde-treated tissue is stable against chemical and enzymatic degradation; however, its calcification and cytotoxicity are severe. Dye-mediated photooxidation is an alternative tissue preservation method that oxidizes the protein with visible light in the presence of a suitable photosensitizer. This article reviews chemical mechanism, research progress, clinical applications future development of these two methods.