Geometry optimization of cantilever-based optical microphones.

The introduction of cantilever-based fiber-optic microphones (FOMs) has proven to be effective in acoustic sensing. Further improvements in cantilevers face two key constraints: the challenge of achieving minimal sizes with sufficient reflective area and the trade-off between sensitivity and response bandwidth. Herein, we present a geometry optimization framework for a cantilever-based FOM that addresses this issue. Employing drumstick-shaped cantilevers housed within a Fabry-Perot (F-P) interferometric structure, we showcase a heightened sensitivity of 302.8 mV/Pa at 1 kHz and a minimum detectable acoustic pressure (MDP) of 2.35 µPa/H z. Notably, these metrics outperform those of the original rectangular cantilever with identical dimensions. Furthermore, our proposed cantilever effectively mitigates the reduction in resonance frequencies, thereby improving the response bandwidth. This geometry optimization framework offers considerable design flexibility and scalability, making it especially suitable for high-performance acoustic sensing applications.

Accelerometer-measured physical activity, sedentary behavior, and risk of incident pelvic organ prolapse: a prospective cohort study in the UK Biobank.

BACKGROUND: Previous studies on physical activity (PA) and pelvic organ prolapse (POP) were largely limited to self-reported PA in athletes, soldiers, and women in postpartum. We aimed to investigate the association of accelerometer-measured PA and sedentary behavior with the risk of POP in middle-aged and elderly women. METHODS: In this prospective cohort derived from the UK Biobank, the intensity and duration of PA and sedentary behavior were measured with wrist-worn accelerometers over a 7-day period in 2013-2015 for 47,674 participants (aged 42.8-77.9 years) without pre-existing POP. Participants were followed up until the end of 2022, during which incident POP was ascertained mainly by the electronic health records. Multivariable-adjusted Cox proportional hazards models and restricted cubic splines were used to assess the associations of interest. Isotemporal substitution models were applied to test the effects of substituting a type of activity with equivalent duration of others. RESULTS: During a median follow-up of 8.0 years, 779 cases of POP were recorded. The duration of light-intensity PA (LPA) was positively whereas sedentary time was negatively associated with the risk of POP. Every additional 1 h/day of LPA elevated the risk of POP by 18% (95% confidence interval [CI], 10%-26%). In contrast, the risk decreased by 5% (95% CI, 0-8%) per 1 h/day increment in sedentary behavior. No associations were found between moderate-intensity PA (MPA) or vigorous-intensity PA (VPA) and POP, except that women who had a history of hysterectomy were more likely to develop POP when performing more VPA (53% higher risk for every additional 15 min/day). Substituting 1 h/day of LPA with equivalent sedentary time was associated with a 18% (95% CI, 11%-24%) lower risk of POP. The risk can also be reduced by 17% (95% CI, 7%-25%) through substituting 30 min/day of LPA with MPA. CONCLUSIONS: More time spent in LPA or less sedentary time was linked to an elevated risk of POP in middle-aged and elderly women, while MPA or VPA was not. Substituting LPA with equivalent duration of sedentary behavior or MPA may lower the risk of POP.

Sensitivity-enhanced Fabry-Perot interferometric fiber-optic microphone using hollow cantilever.

Transducer components are crucial in optimizing the sensitivity of microphones. Cantilever structure is commonly used as a structural optimization technique. Here, we present a novel Fabry-Perot (F-P) interferometric fiber-optic microphone (FOM) using a hollow cantilever structure. The proposed hollow cantilever aims to reduce the effective mass and spring constant of the cantilever, thereby enhancing the sensitivity of the FOM. Experimental results demonstrate that the proposed structure outperforms the original cantilever design in terms of sensitivity. The sensitivity and minimum detectable acoustic pressure level (MDP) can reach 91.40 mV/Pa and 6.20 µPa/Hz at 1.7 kHz, respectively. Notably, the hollow cantilever provides an optimization framework for highly sensitive FOMs.

Near-infrared sensitive differential Helmholtz-based hydrogen sulfide photoacoustic sensors.

A near-infrared (NIR) sub-ppm level photoacoustic sensor for hydrogen sulfide (H2S) using a differential Helmholtz resonator (DHR) as the photoacoustic cell (PAC) was presented. The core detection system was composed of a NIR diode laser with a center wavelength of 1578.13 nm, an Erbium-doped optical fiber amplifier (EDFA) with an output power of ∼120 mW, and a DHR. Finite element simulation software was used to analyze the influence of the DHR parameters on the resonant frequency and acoustic pressure distribution of the system. Through simulation and comparison, the volume of the DHR was 1/16 that of the conventional H-type PAC for a similar resonant frequency. The performance of the photoacoustic sensor was evaluated after optimizing the DHR structure and modulation frequency. The experimental results showed that the sensor had an excellent linear response to the gas concentration and the minimum detection limit (MDL) for H2S detection in differential mode can reach 460.8 ppb.

Effectiveness of Laparoscopic Pectopexy for Pelvic Organ Prolapse Compared with Laparoscopic Sacrocolpopexy.

STUDY OBJECTIVE: To evaluate the clinical benefits of laparoscopic pectopexy vs laparoscopic sacrocolpopexy in women with pelvic organ prolapse (POP). DESIGN: Prospective cohort study. SETTING: A tertiary hospital. PATIENTS: We included 203 patients with POP. INTERVENTIONS: Laparoscopic pectopexy or laparoscopic sacrocolpopexy. MEASUREMENTS AND MAIN RESULTS: Anatomic effectiveness was measured using the POP Quantification system, both before and after operation. Functional recovery effectiveness was evaluated using complications and recurrence rates within 1 year. Quality of life was assessed by the Pelvic Floor Distress Inventory-20 and Incontinence Quality of Life questionnaires at enrollment and postoperative months 3, 6, and 12. Comparisons between groups were performed using t test, chi-square test, and mixed-effects model with repeated measures. The analysis included 203 eligible patients (sacrocolpopexy, 101; pectopexy, 102). The proportion of robotic-assisted surgeries was lower in the pectopexy group than in the sacrocolpopexy group (15.7% vs 41.6%, p <.001). The average operation time of pectopexy was shorter than that of sacrocolpopexy (174.2 vs 187.7 minutes) with a mean difference of 13.5 minutes (95% confidence interval, 3.9-23.0; p = .006). Differences of intraoperative blood loss, length of hospital stay, and postoperative 7-day complications between groups were not significant. Anatomic successes were obtained in both groups with similar improvement in POP Quantification scores. The rate of urinary symptoms recurrence was higher in the pectopexy group (13.7%) than in the sacrocolpopexy group (5.0%) at the 1-year follow-up (odds ratio, 3.1; 95% confidence interval, 1.1-8.8, p = .032). The Pelvic Floor Distress Inventory-20 and Incontinence Quality of Life scores were better improved at postoperative months 3, 6, and 12 for laparoscopic pectopexy than for sacrocolpopexy. CONCLUSION: Laparoscopic pectopexy revealed comparable anatomic success, shorter operation time, and better improvement in quality of life scores of prolapse, colorectal-anal, and urinary symptoms at 1-year follow-up, possibly being an alternative when sacrocolpopexy is not practicable. However, clinicians should pay more attention to the recurrence of urinary symptoms after pectopexy.

FIZZ2 as a Biomarker for Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

PURPOSE: Found in inflammatory zone 2 (FIZZ2) is associated with lung inflammation. The aim of the study was to investigate the expression and utility of FIZZ2 as a marker for chronic obstructive pulmonary disease (COPD). METHODS: Immunohistochemistry was used to detect the expression of FIZZ2 in COPD. The serum concentration of FIZZ2 was measured by enzyme-linked immunosorbent assay and the episodes of acute exacerbations of COPD (AECOPD) in the following year were recorded. RESULTS: FIZZ2 expression was elevated in bronchial epithelial cells (0.217 ± 0.021 vs 0.099 ± 0.010, p < 0.0001) and negatively correlated with the pulmonary function (FEV1/FVC%) (p = 0.0149) and positively correlated with the smoking index (p = 0.0241). Serum level of FIZZ2 in COPD were significantly higher than that in healthy controls (561.6 ± 70.71 vs 52.24 ± 20.52 pg/ml, p < 0.0001) and increased with the COPD severity. Serum levels of FIZZ2 negatively correlated with the pulmonary function [Forced Vital Capacity (FVC), Forced Expiratory Volume (FEV1), FEV1%, FEV1/FVC) (r = - 0.3086, - 0.3529, - 0.3343, and - 0.2676, respectively, p = 0.0003, p < 0.0001, p < 0.0001, p = 0.0014). The expression of human serum FIZZ2 was positively correlated with the smoking index (r = 0.2749, p = 0.0015). There was a positive correlation between the FIZZ2 concentration and the frequency of AECOPD episodes in the following year (r = 0.7291, p < 0.0001). CONCLUSION: FIZZ2 expression was elevated in patients with COPD and its serum concentration might be a potential biomarker for AECOPD.

Ginsenoside metabolite compound K induces apoptosis and autophagy in non-small cell lung cancer cells via AMPK-mTOR and JNK pathways.

Compound K [C-K; 20-O-(ß-d-glucopyranosyl)-20(S)-protopanaxadiol], as a metabolite of ginsenoside, has been verified to have antitumor effects in various cancers, including non-small cell lung cancer (NSCLC). However, the detailed mechanisms of C-K in NSCLC remain largely unknown. In this study, we aimed to evaluate the effect of C-K on apoptosis and autophagy in NSCLC cells as well as its related mechanisms. According to the results, C-K suppressed the proliferation, and led to G1 phase arrest and apoptosis in A549 and H1975 cells. Subsequently, C-K promoted autophagy, as confirmed by the enhanced rate of cells staining positive with acridine orange, increased levels of LC3II and Beclin-1, and with decreased levels of p62 in A549 and H1975 cells. Moreover, 3-methyladenine (3-MA; an inhibitor of autophagy) effectively suppressed the inhibition of proliferation and apoptosis that was induced with C-K. Finally, C-K treatment promoted the activation of the AMPK-mTOR and c-Jun N-terminal kinase (JNK) signaling pathways. Treatment with compound C (AMPK inhibitor) or SP600125 (JNK inhibitor) significantly restrained the inhibition of proliferation, apoptosis, and autophagy induced with C-K in A549 and H1975 cells. In conclusion, this study demonstrates that C-K promotes autophagy-mediated apoptosis in NSCLC via AMPK-mTOR and JNK signaling pathways.

Sensitive and ultrasmall sample volume gas sensor based on a sealed slot waveguide.

Taking advantage of the near-infrared (IR) absorption characteristics of gases, a sensor with an ultrasmall sample volume composed of a sealed slot waveguide and based on evanescent field absorption is proposed in this paper. Compared with a traditional open-slot waveguide, it features small volume antiparticles depositing pollution over the long-term and is insensitive to surroundings. Working at 1645 nm, a large evanescent field ratio of 0.27 is obtained by simulation and optimization; meanwhile, the propagation loss is around 1.6 dB/cm. The needed sample volume of the designed sensor under the structure parameters of w_air=40 nm, h_air=400 nm, and waveguide length=3 cm is approximately 480 µm3, which helps the sensor demonstrate excellent performance for gas analysis with an ultrasmall sample volume.

On-chip integratable all-optical quantizer using cascaded step-size MMI.

We propose a novel all-optical phase shifted quantizer using cascade step-size MMI. The operation principle has been derived in detail. A 3-bit quantizer and a 5-bit quantizer are designed and simulated based on 220-nm SOI platform to verify the feasibility of the scheme, of which the lengths are all below 200 µm. To the best of our knowledge, they have the most compact footprint compared to the existing all-optical quantizers. In the end, the fabrication error analyses of the proposed quantizers are carried out to verify their stability.

Photoacoustic trace gas detection of OCS using a 2.45 mL Helmholtz resonator and a 4823.3 nm ICL light source.

A miniaturized photoacoustic spectroscopy-based gas sensor is proposed for the purpose of detecting sub-ppm-level carbonyl sulfide (OCS) using a tunable mid-infrared interband cascade laser (ICL) and a Helmholtz photoacoustic cell. The tuning characteristics of the tunable ICL with a center wavelength of 4823.3 nm were investigated to achieve the optimal driving parameters. A Helmholtz photoacoustic cell with a volume of ∼2.45 mL was designed and optimized to miniaturize the measurement system. By optimizing the modulation parameters and signal processing, the system was verified to have a good linear response to OCS concentration. With a lock-in amplifier integration time of 10 s, the 1σ noise standard deviation in differential mode was 0.84 mV and a minimum detection limit (MDL) of 409.2 ppbV was achieved at atmospheric pressure and room temperature.

Oral microbial dysbiosis in patients with periodontitis and chronic obstructive pulmonary disease.

Background: Oral microbiota is closely related to the homeostasis of the oral cavity and lungs. To provide potential information for the prediction, screening, and treatment strategies of individuals, this study compared and investigated the bacterial signatures in periodontitis and chronic obstructive pulmonary disease (COPD). Materials and methods: We collected subgingival plaque and gingival crevicular fluid samples from 112 individuals (31 healthy controls, 24 patients with periodontitis, 28 patients with COPD, and 29 patients with both periodontitis and COPD). The oral microbiota was analyzed using 16S rRNA gene sequencing and diversity and functional prediction analysis were performed. Results: We observed higher bacterial richness in individuals with periodontitis in both types of oral samples. Using LEfSe and DESeq2 analyses, we found differentially abundant genera that may be potential biomarkers for each group. Mogibacterium is the predominant genus in COPD. Ten genera, including Desulfovibrio, Filifactor, Fretibacterium, Moraxella, Odoribacter, Pseudoramibacter Pyramidobacter, Scardovia, Shuttleworthia and Treponema were predominant in periodontitis. Bergeyella, Lautropia, Rothia, Propionibacterium and Cardiobacterium were the signature of the healthy controls. The significantly different pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) between healthy controls and other groups were concentrated in genetic information processing, translation, replication and repair, and metabolism of cofactors and vitamins. Conclusions: We found the significant differences in the bacterial community and functional characterization of oral microbiota in periodontitis, COPD and comorbid diseases. Compared to gingival crevicular fluid, subgingival plaque may be more appropriate for reflecting the difference of subgingival microbiota in periodontitis patients with COPD. These results may provide potentials for predicting, screening, and treatment strategies for individuals with periodontitis and COPD.

Intestinal segment and vitamin D3 concentration affect gene expression levels of calcium and phosphorus transporters in broiler chickens.

Two experiments were conducted in this research. Experiment 1 investigated the spatial expression characteristics of calcium (Ca) and phosphorus (P) transporters in the duodenum, jejunum, and ileum of 21-day-old broilers provided with adequate nutrient feed. Experiment 2 evaluated the effects of dietary vitamin D3 (VD3) concentration (0, 125, 250, 500, 1,000, and 2,000 IU/kg) on growth performance, bone development, and gene expression levels of intestinal Ca and P transporters in 1-21-day-old broilers provided with the negative control diet without supplemental VD3. Results in experiment 1 showed that the mRNA levels of calcium-binding protein 28-kDa (CaBP-D28k), sodium-calcium exchanger 1 (NCX1), plasma membrane calcium ATPase 1b (PMCA1b), and IIb sodium-phosphate cotransporter (NaPi-IIb) were the highest in the broiler duodenum. By contrast, the mRNA levels of inorganic phosphate transporter 1 (PiT-1) and 2 (PiT-2) were the highest in the ileum. Results in experiment 2 showed that adding 125 IU/kg VD3 increased body weight gain (BWG), feed intake (FI), bone weight, and percentage and weight of Ca and P in the tibia and femur of 1-21-day-old broilers compared with the negative control diet (p < 0.05). The rise in dietary VD3 levels from 125 to 1,000 IU/kg further increased the BWG, FI, and weights of the bone, ash, Ca, and P (p < 0.05). No difference in growth rate and leg bone quality was noted in the broilers provided with 1,000 and 2,000 IU/kg VD3 (p > 0.05). Supplementation with 125-2,000 IU/kg VD3 increased the mRNA abundances of intestinal Ca and P transporters to varying degrees. The mRNA level of CaBP-D28k increased by 536, 1,161, and 28 folds in the duodenum, jejunum, and ileum, respectively, after adding 1,000 IU/kg VD3. The mRNA levels of other Ca and P transporters (PMCA1b, NCX1, NaPi-IIb, PiT-1, and PiT-2) increased by 0.57-1.74 folds by adding 1,000-2,000 IU/kg VD3. These data suggest that intestinal Ca and P transporters are mainly expressed in the duodenum of broilers. Moreover, the addition of VD3 stimulates the two mineral transporter transcription in broiler intestines.

Hybridizing Niching, Particle Swarm Optimization, and Evolution Strategy for Multimodal Optimization.

Multimodal optimization problems (MMOPs) are common problems with multiple optimal solutions. In this article, a novel method of population division, called nearest-better-neighbor clustering (NBNC), is proposed, which can reduce the risk of more than one species locating the same peak. The key idea of NBNC is to construct the raw species by linking each individual to the better individual within the neighborhood, and the final species of the population is formulated by merging the dominated raw species. Furthermore, a novel algorithm is proposed called NBNC-PSO-ES, which combines the advantages of better exploration in particle swarm optimization (PSO) and stronger exploitation in the covariance matrix adaption evolution strategy (CMA-ES). For the purpose of demonstrating the performance of NBNC-PSO-ES, several state-of-the-art algorithms are adopted for comparisons and tested using typical benchmark problems. The experimental results show that NBNC-PSO-ES performs better than other algorithms.

Polysaccharides derived from Astragalus membranaceus and Glycyrrhiza uralensis improve growth performance of broilers by enhancing intestinal health and modulating gut microbiota.

This study was conducted to investigate the effects of dietary supplementation of polysaccharides derived from Astragalus membranaceus and Glycyrrhiza uralensis on growth performance, intestinal health, and gut microbiota composition in broilers. A total of 480 one-day-old male Arbor Acres broilers were randomly divided into 4 treatments with 6 replicates comprising 20 broilers each. Treatments included: basal diet without antibiotics (CON); basal diet supplemented with 500 mg/kg terramycin calcium (ANT); basal diet supplemented with 300 mg/kg Astragalus membranaceus polysaccharides (APS); and basal diet supplemented with 150 mg/kg Glycyrrhiza uralensis polysaccharides (GPS). The results showed that ANT, AP,S and GPS supplementation significantly increased average daily gain (ADG) and decreased feed conversion ratio (FCR) of broilers from 1 to 42 d of age. At 42 d, serum immunoglobulin A (IgA), immunoglobulin M (IgM) and immunoglobulin G (IgG) levels of the APS and GPS group were notably higher than those of the CON group, while serum levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) as well as diamine oxidase (DAO) activity in the APS and GPS group were obviously decreased. Moreover, diets supplemented with APS and GPS could significantly increase villus height (VH) and the ratio of villus height to crypt depth (VH/CD) and remarkably upregulated occludin, claudin-1 and mucin-2 (MUC2) mRNA expression in duodenum, jejunum, and ileum of broilers. In addition, 16S rRNA gene sequencing revealed that APS and GPS supplementation altered cecal microbial diversity and composition in broilers. Higher Shannon index was observed in the APS and GPS group compared with the CON group, while GPS supplementation could also increase Chao1 index and Observed species. The result of Principal coordinate analysis (PCoA) showed that microbial community in the CON, ANT, APS, and GPS group clustered separately. Notably, both APS and GPS supplementation significantly decreased the abundance of Bacteroidetes, Bacteroides, Faecalibacterium, Desulfovibrio, and Butyricicoccus, while increased the abundance of Firmicutes, Prevotella, Parabacteroides, Ruminococcus, and Alistipes. The correlation analysis showed that the changes in cecal microbial composition induced by dietary APS and GPS supplementation were closely associated with the alteration of the phenotype of broilers including ADG, FCR, TNF-α, IL-1ß, IL-6, IgA, IgG, DAO, Occludin, Claudin-1, ZO-1, and MUC2. In conclusion, polysaccharides derived from Astragalus membranaceus and Glycyrrhiza uralensis could improve growth performance of broilers by enhancing intestinal health and modulating gut microbiota.

Sensitivity enhanced NIR photoacoustic CO detection with SF6 promoting vibrational to translational relaxation process.

A challenge for slowly relaxing carbon monoxide (CO) molecules detection using photoacoustic spectroscopy (PAS) is to promote the vibration-translation (V-T) relaxation process. Addressing this challenge, a sensitivity enhanced photoacoustic CO sensor with sulfur hexafluoride (SF6) as the promotor is investigated and demonstrated. A 1568 nm near-infrared (NIR) laser diode and a customized optical amplifier are used as the excitation source to generate the photoacoustic signal. A differential photoacoustic cell is simulated and designed to obtain identical laminar flow distribution in the resonant cell to suppress the flow noise. The modulation frequency and added SF6 volume ratio are optimized experimentally to achieve optimal sensitivity. Feasibility and performance of the CO sensor with a small amount of SF6 as promotor is discussed and evaluated, obtaining a ~ 2 times improvement of signal value compared to the one with pure N2 background and resulting in a minimum detection limit of 467.5 ppb for CO detection.

Effects of Compound Polysaccharides Derived from Astragalus and Glycyrrhiza on Growth Performance, Meat Quality and Antioxidant Function of Broilers Based on Serum Metabolomics and Cecal Microbiota.

This study aimed to evaluate the effects of dietary supplementation of compound polysaccharides derived from Astragalus and Glycyrrhiza on growth performance, meat quality, antioxidant function, cecal microbiota and serum metabolomics of broilers. A total of 480 one-day-old male Arbor Acres (AA) broilers were randomly divided into four treatments with six replicates comprising 20 broilers each. Treatments: CON group was the basal diet; ANT group was supplemented with Terramycin calcium; LAG group was supplemented with 150 mg/kg Astragalus polysaccharides and 75 mg/kg Glycyrrhiza polysaccharides; HAG group was supplemented with 300 mg/kg Astragalus polysaccharides and 150 mg/kg Glycyrrhiza polysaccharides. The results showed that LAG and HAG supplementation increased growth performance, antioxidant function and meat quality compared with the CON group and ANT group and, especially, the effect of LAG treatment was better than HAG. Analysis of cecal microbiota showed that LAG and HAG supplementation altered cecal microbial diversity and composition in broilers. Serum metabolomics analysis showed that a total of 193 differential metabolites were identified in CON and LAG groups, which were mainly enriched in linoleic acid metabolism and glutathione metabolism pathways. Moreover, there was a close correlation between serum metabolites, cecal microbiota and phenotypic indicators. Conclusion: Dietary supplementation of 150 mg/kg Astragalus polysaccharides and 75 mg/kg Glycyrrhiza polysaccharides could improve the growth performance, antioxidant function and meat quality of broilers by changing the serum metabolites and cecal microbiota composition.

Age quadratically affects intestinal calcium and phosphorus transporter gene expression in broiler chickens.

OBJECTIVE: This research aimed to evaluate the effects of age on growth, tibia development, and intestinal calcium (Ca) and phosphorus (P) transporter gene expressions in broiler chickens. METHODS: A total of 224 male Arbor Acres broilers were fed with nutrient-adequate diets and reared in eight cages (28 broilers per cage). Eight broilers (one broiler per cage) were selected and killed at 5, 10, 15, 20, 25, 30, 35, and 40 days of age, respectively. RESULTS: Body weight continuously increased with age of broiler chickens from 5 to 40 days. The bone weight, ash weight, diameter, and length of the tibia also increased with broiler age. By contrast, the tibia ash, Ca, and P percentages quadratically changed with age (p<0.001), and the highest values of mineral contents were observed at 20, 25, and 25 days of age, respectively. The mRNA abundances of calcium-binding protein 28-kDa (CaBP-D28k), sodium-calcium exchanger 1 (NCX1), and plasma membrane ATPase 1b (PMCA1b) increased from 5 to 25 days and then decreased up to 40 days. Similar results were noted in the mRNA abundances of IIb sodium-phosphate cotransporter (NaPi-IIb), inorganic phosphate transporter 1 (PiT-1), inorganic phosphate transporter 2 (PiT-2), nuclear vitamin D receptor (nVDR), and membrane vitamin D receptor (mVDR). The mRNA abundances of Ca and P transporters and VDRs were the highest at 25 days of age. CONCLUSION: These data indicate that age quadratically affects intestinal Ca and P transporter gene expression and mineral absorption capacity in broiler chickens.

Degradation of zearalenone and aflatoxin B1 by Lac2 from Pleurotus pulmonarius in the presence of mediators.

The contamination of foods and feeds with mycotoxins has been an issue of global significance. For mycotoxin detoxification, enzymatic biodegradation using laccase has received much attention. In this study, a laccase gene lac2 from the fungus Pleurotus pulmonarius was expressed in the Pichia pastoris X33 yeast strain to produce recombinant proteins. Enzymatic properties of recombinant Lac2 and its ability to degrade zearalenone (ZEN) and Aflatoxin B1 (AFB1) in the presence of four mediators (ABTS, TEMPO, AS and SA) were investigated. Result showed that the optimum pH and temperature of recombinant Lac2 were 3.5 and 55 °C, respectively. Lac2 was not sensitive to heat and stable under both acidic and alkaline conditions. Lac2-ABTS and Lac2-AS were efficient systems for ZEN degradation over a wide range of pH (4-8) and temperature (40-60 °C). Lac2-AS was the most efficient system for AFB1 degradation, reaching 99.82% of degradation at pH 7 and 37 °C after 1 h of incubation. Finally, the Lac2-mediator oxidation products were structurally characterized. This study lays a solid foundation for the application of Lac2 laccase combined with AS for degrading mycotoxin in food and feed.

The Impact of Berberine on Intestinal Morphology, Microbes, and Immune Function of Broilers in Response to Necrotic Enteritis Challenge.

The objective of this study was to explore the therapeutic effects of berberine on necrotic enteritis (NE) in broilers caused by Clostridium perfringens. A total of 240 1-day-old Arbor Acres chicks were divided into four groups, as negative controls (NC), positive controls (PC), berberine- (BER-) treated, or lincomycin- (LMY-) treated groups. Broilers were challenged with C. perfringens at 15-21 days of age, followed by BER or LMY supplied in drinking water for 7 days. Experimental results showed that C. perfringens infection significantly decreased growth performance and increased intestinal necrosis index and the number of C. perfringens present to 6.45 Log10CFU/g (P < 0.001). Proinflammatory cytokines in the ileum were significantly increased, but the expression of ileal tight junction proteins occludin and claudin-1 was significantly reduced. Both BER and LMY ameliorated some of these observations. Compared with the PC group, the number of C. perfringens in the cecum was significantly decreased following treatment (P < 0.001), and growth performance and small intestine morphology were similar to those of the NC group (P > 0.05). IL-1ß, IL-6, and TNF-α levels as well as occludin and claudin-1 expression were also significantly improved (P < 0.05). BER has the potential to replace antibiotics for NE caused by C. perfringens.

Clostridium butyricum Alleviates Enterotoxigenic Escherichia coli K88-Induced Oxidative Damage Through Regulating the p62-Keap1-Nrf2 Signaling Pathway and Remodeling the Cecal Microbial Community.

Clostridium butyricum (CB) can enhance antioxidant capacity and alleviate oxidative damage, but the molecular mechanism by which this occurs remains unclear. This study used enterotoxigenic Escherichia coli (ETEC) K88 as a pathogenic model, and the p62-Keap1-Nrf2 signaling pathway and intestinal microbiota as the starting point to explore the mechanism through which CB alleviates oxidative damage. After pretreatment with CB for 15 d, mice were challenged with ETEC K88 for 24 h. The results suggest that CB pretreatment can dramatically reduce crypt depth (CD) and significantly increase villus height (VH) and VH/CD in the jejunum of ETEC K88-infected mice and relieve morphological lesions of the liver and jejunum. Additionally, compared with ETEC-infected group, pretreatment with 4.4×106 CFU/mL CB can significantly reduce malondialdehyde (MDA) level and dramatically increase superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels in the serum. This pretreatment can also greatly increase the mRNA expression levels of tight junction proteins and genes related to the p62-Keap1-Nrf2 signaling pathway in the liver and jejunum in ETEC K88-infected mice. Meanwhile, 16S rDNA amplicon sequencing revealed that Clostridium disporicum was significantly enriched after ETEC K88 challenge relative to the control group, while Lactobacillus was significantly enriched after 4.4×106 CFU/mL CB treatment. Furthermore, 4.4×106 CFU/mL CB pretreatment increased the short-chain fatty acid (SCFA) contents in the cecum of ETEC K88-infected mice. Moreover, we found that Lachnoclostridium, Roseburia, Lactobacillus, Terrisporobacter, Akkermansia, and Bacteroides are closely related to SCFA contents and oxidative indicators. Taken together, 4.4×106 CFU/mL CB pretreatment can alleviate ETEC K88-induced oxidative damage through activating the p62-Keap1-Nrf2 signaling pathway and remodeling the cecal microbiota community in mice.