Inhibition of starch digestion by phenolic acids with a cinnamic acid backbone: Structural requirements for the inhibition of α-amylase and α-glucosidase

This study investigated the inhibition mechanism of cinnamic acid-based phenolic acids (cinnamic acid: CIA, 3,4-dimethoxy cinnamic acid: 3,4-mCIA, caffeic acid: CA, ferulic acid: FA) on starch digestion. CA, FA, and 3,4-mCIA contributed to reducing the rapidly digested starch content and increasing the resistant starch content. The enzyme activity inhibition results responded that the four phenolic acids inhibited α-amylase activity better than α-glucosidase. The order of IC50 against α-amylase and α-glucosidase was CA > FA > 3,4-mCIA > CIA. Phenolic acid's benzene ring formed conjugated Pi-systems with the amino acid residues of α-amylase. Salt-bridge interactions were the main driving forces for the binding of phenolic acids to α-glucosidase. The binding was stabilized by the hydroxyl (OH) group and the methoxy on the benzene ring, where the OH exerted a better effect. These results illuminate the inhibition mechanism of starch digestion with cinnamic acid-based phenolic acids from an interaction perspective.

Proteomic Comparisons of Caprine Milk Whole Cream Buttermilk Whey and Cheese Whey Cream Buttermilk

Buttermilk, a potential material used to produce milk fat globule membrane (MFGM), is obtained as a byproduct of butter making from milk whole cream and cheese whey cream. This study investigated the effects of rennet and acid coagulation on the protein profiles of buttermilk rennet-coagulated whey (BRW) and buttermilk acid-coagulated whey (BAW). They were compared to those of whey cream buttermilk (WCB). Rennet coagulation was more efficient in removing casein, while retaining more IgG and lactoferrin than acid coagulation. BRW had more MFGM than BAW. Butyrophilin, xanthine dehydrogenase, and mucin1 were significantly higher (P < 0.05) in BRW, while fatty acid-binding protein 3 was enriched in BAW. KEGG analysis showed that complement and coagulation cascades had the greatest differences, and the abundance of proteins involved in this signaling pathway in BRW and BAW was higher, suggesting their potential anticoagulant and anti-inflammatory activity. BAW had higher apolipoprotein A4 and transcobalamin 2, which are essential carriers for transporting long-chain fatty acids and vitamin B12 from the intestine to the blood. Therefore, BAW intake might improve lipids and vitamin B12 absorption. This study can help deepen the understanding of protein composition of MFGM-enriched whey and facilitate the production of MFGM proteins for infants and old-aged populations.

Differentiated digestion resistance and physicochemical properties of linear and α-1,2/α-1,3 branched isomaltodextrins prepared by 4,6-α-glucanotransferase and branching sucrases

Isomaltodextrins (IMDs) are starch-based dietary fibers (DF) prepared enzymatically, which show great potential as a functional food ingredient. In this study, a series of novel IMDs with diverse structures were generated by 4,6-α-glucanotransferase GtfBΔN from Limosilactobacillus fermentum NCC 3057, combined with two α-1,2 and α-1,3 branching sucrases. Results indicated that α-1,2 and α-1,3 branching significantly improved the DF contents of α-1,6 linear products up to 60.9-62.8%. When altering the ratios of [sucrose]/[maltodextrin], IMDs containing 25.8-89.0% α-1,6 bonds, 0-59.6% α-1,2 bonds and 0-35.1% α-1,3 bonds and Mw ranged from 1967 to 4876 Da were obtained. Physicochemical property analysis showed that grafting with α-1,2 or α-1,3 single glycosyl branches can improve the solubility of the α-1,6 linear product, in which α-1,3 branched products were better. Moreover, α-1,2 or α-1,3 branching did no effect on the viscosity of the products but Mw did, the larger Mw the greater viscosity. In addition, α-1,6 linear and α-1,2 or α-1,3 branched IMDs all exhibited strong acid-heating stabilities, freeze-thaw stabilities, and good resistance to browning caused by the Maillard reaction. Branched IMDs showed excellent storage stabilities at room temperature for one year at a concentration of 60%, whereas 45% α-1,6 linear IMD precipitated quickly within 12 h. Most importantly, α-1,2 or α-1,3 branching remarkably increased the contents of resistant starch in the α-1,6 linear IMDs to 74.5-76.8%. These clear qualitative assessments demonstrated the outstanding processing and application properties of the branched IMDs and were expected to provide valuable perspectives toward the technological innovation of functional carbohydrates.

[Detection rate and clinical characteristics of vulvar squamous intraepithelial lesion]

Objective: To explore the detection rate, clinical characteristics of vulvar squamous intraepithelial lesion (SIL). Methods: Women diagnosed with vulvar high-grade squamous intraepithelial lesions (HSIL) through colposcopy-guided biopsy from January 1, 2018 to August 31, 2022 in Obstetrics and Gynecology Hospital of Fudan University were included in a 1∶1 ratio with patients diagnosed with vulvar low-grade squamous intraepithelial lesions (LSIL) during the same period. Clinical characteristics including human papillomavirus (HPV) infection rate, genotype, cytology result, colposcopy impression, and lesion location were retrospectively analyzed. Results: (1) The proportion of vulvar SIL detected by colposcopy-guided biopsy increased annually from 2018 to 2022, with rates of 1.64% (740/45 057), 2.34% (1 110/47 402), 2.68% (1 108/41 335), 3.26% (1 536/47 078), 3.31% (667/20 155), with an average rate of 2.57% (5 161/201 027). (2) A total of 1 096 cases of vulvar HSIL and 1 096 cases of vulvar LSIL were included. The overall infection rate of HPV was 92.7% (1 993/2 150), with higher infection rate in vulvar HSIL patients than that in vulvar LSIL patients [96.0% (1 012/1 054) vs 89.5% (981/1 096); χ2=33.62, P<0.001]. Among vulvar HSIL patients, the common HPV genotype from high to low were HPV 16 (66.7%), HPV 52 (14.3%), and HPV 58 (10.0%). For vulvar LSIL patients, the most common HPV genotype were respectively HPV 16 (24.9%), HPV 6 (20.1%) and HPV 52 (17.1%). The overall sensitivity rate of cytology was 53.6%, with no significance difference between vulvar LSIL and HSIL groups (54.3% vs 52.9%; χ2=0.40, P=0.526). The accuracy of colposcopy impression for vulvar HSIL was lower than that for vulvar LSIL [40.2% (163/405) vs 81.7% (380/465); χ2=158.72, P<0.001]. About 57.3% (1 257/2 192) of the patients had concomitant cervical and vaginal lesions, with a higher rate in vulvar HSIL group than that in vulvar LSIL group [62.6% (686/1 096) vs 52.1% (571/1 096); χ2=24.67, P<0.001]. Unifocal lesion was the main type, with no significance difference between vulvar LSIL and HSIL groups [81.4% (381/468) vs 82.5% (386/468); χ2=0.18, P=0.671]. The most common lesion locations were the posterior commissure, followed by labia minora, vaginal vestibule, labia majora, perianal and clitoris. Conclusions: The detection rate of vulvar SIL under colposcopy is about 3%, and the infection rate of HPV is 92.7%. Vulvar SIL, especially vulvar HSIL, is likely to cause concomitant cervical and vaginal lesions. The accuracy of colposcopy in diagnosing vulvar HSIL is low. Therefore a comprehensive and careful examination of the vulva is necessary and suspicious vulvar lesions should be undergone colposcopy-guided biopsy for diagnosis.

Gastrointestinal digestibility of micellar casein dispersions: Effects of caprine vs bovine origin, and partial colloidal calcium depletion using in vitro digestion models for the adults and elderly

In vitro coagulation and digestion of caprine and bovine micellar casein concentrate (MCC) with or without partial colloidal calcium depletion (deCa) were studied under simulated adult and elderly conditions. Gastric clots were smaller and looser for caprine than bovine MCC, and were further looser with deCa and under elderly condition for both caprine and bovine MCC. Casein hydrolysis and concomitant formation of large peptides was faster for caprine than bovine MCC, and with deCa and under adult condition for caprine and bovine MCC. Formation of free amino groups and small peptides were faster for caprine MCC, and with deCa and under adult condition. Upon intestinal digestion, proteolysis occurred rapidly, and was faster under adult condition, but showed less differences with increasing digestion between caprine and bovine MCC, and with and without deCa. These results suggested weakened coagulation and greater digestibility for caprine MCC and MCC with deCa under both conditions.

[Comparative study of next generation sequencing and immunohistochemistry on molecular classification of endometrial carcinoma]

Objective: To investigate the differences in molecular classification of endometrial carcinoma (EC) between various technical methods and to explore molecular classification schemes suitable for Chinese population. Methods: The study used a comprehensive scheme of next generation sequencing (NGS) and immunohistochemistry for molecular classification of 254 EC cases that were obtained at Department of Pathology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China from April 2021 to March 2022. According to the recommended threshold of Sanger sequencing which was approximate-20% variant allele fraction (VAF), NGS data were extracted to simulate the results of Sanger sequencing. Results: The 254 EC patients had a mean age of 51 years (range, 24 to 89 years). Combination of POLE (9-14 exons), TP53 total exons and microsatellite instability (MSI) detection was a better single scheme than NGS alone, while combination of MSI fragment analysis and conventional immunohistochemistry was the best solution and seemed best aligned with TCGA data and recent studies. POLE ultramuted type, mismatch repair defect type, TP53 mutant type and non-specific molecular characteristic type accounted for 11.4% (29/254), 31.5% (80/254), 22.4% (57/254) and 34.6% (88/254) of the cases, respectively. If Sanger sequencing was adopted for POLE and TP53 detection, the frequencies of these EC types were 9.1% (23/254), 31.5% (80/254), 12.9% (33/254) and 46.6% (118/254), respectively, with greatly increasing non-specific molecular characteristics cases. If POLE was detected by Sanger sequencing and others by immunohistochemistry, they were 9.1% (23/254), 42.2% (92/218), 13.8% (35/254) and 40.9% (105/254), respectively, with increasing the false positive rates of the mismatch repair defect group. Conclusions: Small and medium-sized NGS panels with MSI detection is a better solution than NGS alone. Sanger sequencing is currently available for POLE mutation detection, which is not sensitive enough for TP53 mutation detection, and seems equivalent to the efficiency of TP53 by immunohistochemistry. Further optimization of small and medium-sized NGS panels covering MSI detection and POLE and TP53 full exons may be the best choice for the future to meet national conditions.

Structural characterization of slow digestion dextrin synthesized by a combination of α-glucosidase and cyclodextrin glucosyltransferase and its prebiotic potential on the gut microbiota in vitro

Starch-based dietary fibers are at the forefront of functional ingredient research. In this study, a novel water-soluble slow digestion dextrin (SDD) was synthesized by synergy of α-glucosidase and cyclodextrin glucosyltransferase and characterized. Results showed that SDD exhibited high solubility, low viscosity, and resistance to digestive enzymes, and also showed an increased dietary fiber content of 45.7% compared with that of α-glucosidase catalysis alone. Furthermore, SDD was used as the sole carbon source to ferment selected intestinal strains and human fecal microflora in vitro to investigate its prebiotic effects. It was found that SDD could markedly enriched the abundance of Bifidobacterium, Veillonella, Dialister, and Blautia in human gut microflora and yielded higher total organic acid. The combination of α-glucosidase and cyclodextrin glucosyltransferase in this study showed valuable potential for the preparation of a novel slow digestion dextrin with good physicochemical properties and improved prebiotic effects.

[Efficacy of Hintermann calcaneal lengthening osteotomy for flexible flatfoot]

Objective: To investigate the clinical efficacy of Hintermann osteotomy (H-LCL) for flexible flatfoot. Methods: A follow-up study. Clinical data of 30 patients with flexible flatfoot treated with H-LCL operation from January 2020 to December 2021 in Sports Medical Center of the First Affiliated Hospital of Army Medical University were retrospectively analyzed. There were 8 males and 22 females, with a mean age of (39.0±15.2) years. The mean time from symptom onset to the diagnosis［M（Q₁，Q₃）］was 24.0 (5.5, 102.0) months. The functional and imaging scores of the patients before and after the last follow-up were compared to evaluate the clinical efficacy of the operation. The functional scores included American Orthopedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS) of pain, pain interference (PI) and physical function (PF) index in Patient-Reported Outcomes Measurement Information System (PROMIS). And the imaging scores included Meary's angle, calcaneal pitch angle, calcaneal valgus angle and talonavicular coverage angle. Results: The mean operation time was (82.3±24.4) min, and the follow-up periods was (17.9±6.9) months. At the last follow-up, VAS of pain [M(Q₁, Q₃)] decreased from 5 (4, 6) to 2 (1, 2); PI decreased from 59.8±5.0 to 44.6±5.7; AOFAS increased from 65.2±10.0 to 85.8±3.3; PF increased from 50 (48.5,51.0) to 58.5 (54.0, 66.0); Meary's angle (antero-posterior image) decreased from 15.7° (10.1°, 29.2°) to 3.9° (2.6°, 5.3°); Meary's angle (lateral image) decreased from 13.5°±6.8° to 4.4°±2.6°; calcaneal pitch angle increased from 14.0°±3.3° to 18.6°±4.2°; calcaneal valgus angle decreased from 12.6°±7.3° to 4.3°±2.5°; and talonavicular coverage angle decreased from 20.9°±10.7° to 7.7°±5.2°. The up-mentioned parameters were all improved statistically significant at the last follow-up when compared with those before the operation (all P<0.05). Conclusion: H-LCL brings a significant improvement of clinical outcome scores and good radiological correction of flatfoot deformities in correcting flexible flatfoot, it conforms to the anatomical characteristics of the subtalar joint.

Enhancing 2-O-α-D-glucopyranosyl-L-ascorbic acid synthesis by weakening the acceptor specificity of CGTase toward glucose and maltose

2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G) is a stable derivative of L-ascorbic acid (L-AA), which has been widely used in food and cosmetics industries. Sugar molecules, such as glucose and maltose produced by cyclodextrin glycosyltransferase (CGTase) during AA-2G synthesis may compete with L-AA as the acceptors, resulting in low AA-2G yield. Multiple sequence alignment combined with structural simulation analysis indicated that residues at positions 191 and 255 of CGTase may be responsible for the difference in substrate specificity. To investigate the effect of these two residues on the acceptor preference and the AA-2G yield, five single mutants Bs F191Y, Bs F255Y, Bc Y195F, Pm Y195F and Pm Y260F of three CGTases from Bacillus stearothermophilus NO2 (Bs), Bacillus circulans 251 (Bc) and Paenibacillus macerans (Pm) were designed for AA-2G synthesis. Under optimal conditions, the AA-2G yields of the mutants Bs F191Y and Bs F255Y AA-2G were 34.3% and 7.9% lower than that of Bs CGTase, respectively. The AA-2G yields of mutant Bc Y195F, Pm Y195F and Pm Y260F were 45.8%, 36.9% and 12.6% higher than those of wild-type CGTases, respectively. Kinetic studies revealed that the residues at positions 191 and 255 of the three CGTases were F, which decreased glucose and maltose specificity and increased L-AA specificity. This study not only proposes for the first time that the AA-2G yield can be improved by weakening the acceptor specificity of CGTase toward sugar byproducts, but also provides new insight on the modification of CGTase that catalyze the double-substrate transglycosylation reaction.

Multiple approaches of loop region modification for thermostability improvement of 4,6-α-glucanotransferase from Limosilactobacillus fermentum NCC 3057

4,6-α-glucanotransferase (4,6-α-GT), as a member of the glycoside hydrolase 70 (GH70) family, converts starch/maltooligosaccharides into α,1-6 bond-containing α-glucan and possesses potential applications in food, medical and related industries but does not satisfy the high-temperature requirement due to its poor thermostability. In this study, a 4,6-α-GT (ΔGtfB) from Limosilactobacillus fermentum NCC 3057 was used as a model enzyme to improve its thermostability. The loops of ΔGtfB as the target region were optimized using directed evolution, sequence alignment, and computer-aided design. A total of 11 positive mutants were obtained and iteratively combined to obtain a combined mutant CM9, with high resistance to temperature (50 °C). The activity of mutant CM9 was 2.08-fold the activity of the wild type, accompanied by a 5 °C higher optimal temperature, a 5.76 °C higher melting point (T_m, 59.46 °C), and an 11.95-fold longer half-life time (t_1/2). The results showed that most of the polar residues in the loop region of ΔGtfB are mutated into rigid proline residues. Molecular dynamics simulation demonstrated that the root mean square fluctuation of CM9 significantly decreased by "Breathing" movement reduction of the loop region. This study provides a new strategy for improving the thermostability of 4,6-α-GT through rational loop region modification.

Purification and characterization of aspartic protease from Aspergillus niger and its efficient hydrolysis applications in soy protein degradation

BACKGROUND

Adding acid protease to feed can enhance protein digestibility, boost feed utilization, and stimulate the growth of animals in breading industry. In order to obtain an acid protease with high hydrolysis efficiency to plant protein, in this study, an aspartic protease from Aspergillus niger was heterologous expressed in Pichia pastoris (P. pastoris). The enzymatic properties and application in soybean protein degradation were also studied.

RESULTS

In our investigation, the high aspartic protease (Apa1) activity level of 1500 U/mL was achieved in 3 L bioreactor. After dialysis and anion exchange chromatography, the total enzyme activity and specific enzyme activity were 9412 U and 4852 U/mg, respectively. The molecular weight of the purified protease was 50 kDa, while the optimal pH and temperature were 3.0 and 50 °C, respectively. It was stable at pH 2.0-5.0 and 30-60 °C. Apa1 was used to hydrolyze soybean isolate protein (SPI) at 40 °C and pH 3.0, and a high hydrolysis degree (DH) of 61.65% was achieved. In addition, the molecular weight distribution of SPI hydrolysis products was studied, the result showed that the hydrolysis products were primarily oligopeptides with molecular weights of 189 Da or below.

CONCLUSIONS

In this study, Apa1 was successfully expressed in P. pastoris and high expression level was obtained. In addition, the highest protein hydrolysis rate to SPI degradation so far was achieved. The acid protease in this study provides a new protease that is suitable for the feed industry, which will be very helpful to improve the feed utilization and promote the development of the breeding industry.

[Genetic variations in four geographical isolates of Gohieria fusca based on cytochrome b and internal transcribed spacer genes]

OBJECTIVE

To investigate the genetic diversity and genetic differentiation of different geographical isolates of Gohieria fusca.

METHODS

G. fusca isolates were sampled from Wuhu (WH), Bengbu (BB) and Bozhou cities (BZ) of Anhui Province and Jiaxing City of Zhejiang Province (JX). Mitochondrial cytochrome b (Cytb) and ribosomal internal transcribed spacer (ITS) genes were amplified in WH, BB, BZ and JX isolates of G. fusca using PCR assay. The gene sequences were edited and aligned using the software Chromas 2 and DNASTAR 1.00, and the haplotype, haplotype diversity (Hd) and nucleotide polymorphism (Pi) of each isolate were calculated using the software DnaSP 5.10.00. The genetic differentiation among isolates (F_st) and gene flow value (N_m) were estimated using the software MEGA 10.2, and a phylogenetic tree was built. Tests of neutrality and analysis of molecular variance (AMOVA) were performed using the software Arlequin 3.1 and a haplotype network was built based on the Median-Joining network using the software Network 10.2.

RESULTS

PCR assay showed that the sizes of the Cytb and ITS genes were 372 bp and 1 301 to 1 320 bp, respectively. All four isolates of G. fusca presented high genetic diversity based on mitochondrial Cytb and ITS genes (Hd = 0.804, Pi = 0.006 91). AMOVA showed genetic differentiation among geographical isolates of G. fusca (F_st = 0.202 40, P < 0.05), and the genetic variation was mainly caused by intra-population variations (79.76%). Gene flow analysis showed a high level of gene flow among G. fusca isolates (N_m > 1). Tests of neutrality based on Cytb gene measured a Tajima's D value of -1.796 31 (P < 0.05) and a Fu's FS value of -3.293 98 (P < 0.05) in WH isolate of G. fusca, indicating population expansion in WH isolate of G. fusca. Haplotype network analysis and phylogenetic analysis revealed no remarkable geographical distribution pattern among different geographical isolates of G. fusca. All four isolates of G. fusca presented high genetic diversity (Hd = 0.985, Pi = 0.011 97). AMOVA showed moderate level of genetic differentiation between four isolates (F_st = 0.104 62, P < 0.05). The tests of neutrality based on ITS genes measured a Tajima's D value of -6.088 20 and a Fu's FS value of -1.935 99 (both P > 0.05) in the whole isolate of G. fusca, indicating no obviously population expansion.

CONCLUSIONS

The four geographical isolates of G. fusca have high genetic diversity and remarkable genetic differentiation. Since a high level of gene flow is detected among different geographical isolates of G. fusca, no obvious geographical distribution pattern of G. fusca is found.

Producing 2-O-α-D-glucopyranosyl-L-ascorbic acid by modified cyclodextrin glucosyltransferase and isoamylase

In this study, site saturation mutagenesis was performed on the - 3 (R44, D86, S90, and D192) and - 6 subsite (Y163, G175, G176, and N189) of Bacillus stearothermophilus NO2 cyclodextrin glucosyltransferase to enhance its specificity for the donor substrate maltodextrin for 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G) preparation. The AA-2G yields produced by the mutants S90D, G176H, and S90D/G176H were 181, 171, and 185 g/L, respectively. Our previous study found that the mutant K228R/M230L also increased the AA-2G yield. Therefore, the mutants S90D, G176H, S90D/G176H, and K228R/M230L were further used to generate combinatorial mutants. Among these mutants, the highest AA-2G yield (217 g/L) was produced by S90D/K228R/M230L with 500 g/L maltodextrin as the glucosyl donor, which was 56 g/L higher than that produced by wild-type CGTase. In addition, AA-2G was prepared by adding isoamylase to hydrolyze α-1,6 glucosidic linkages in maltodextrin that could not be utilized by CGTase to improve the utilization rate of maltodextrin. The addition of isoamylase reduced the concentration of maltodextrin from 500 to 350 g/L, while the AA-2G yield remained high (208 g/L). The preparation of AA-2G by complexing isoamylase with mutant S90D/K228R/M230L reduced the maltodextrin concentration by 150 g/L, while the AA-2G yield increased by 47 g/L than preparation with wild-type CGTase alone, which laid a foundation for the large-scale preparation of AA-2G. KEY POINTS: • Mutants exhibited improved maltodextrin specificity. • Mutant S90D/K228R/M230L produced high yield of AA-2G with maltodextrin as substrate. • AA-2G was first synthesized by a combination of isoamylase and CGTase.

Thermostability modification of β-mannanase from Aspergillus niger via flexibility modification engineering

Introduction

β-Mannanases can hydrolyze mannans, which are widely available in nature. However, the optimum temperature of most β-mannanases is too low to be directly utilized in industry.

Methods

To further improve the thermostability of Anman (mannanase from Aspergillus niger CBS513.88), B-factor and Gibbs unfolding free energy change were used to modify the flexible of Anman, and then combined with multiple sequence alignment and consensus mutation to generate an excellent mutant. At last, we analyzed the intermolecular forces between Anman and the mutant by molecular dynamics simulation.

Results

The thermostability of combined mutant mut5 (E15C/S65P/A84P/A195P/T298P) was increased by 70% than the wild-type Amman at 70°C, and the melting temperature (Tm) and half-life (t1/2) values were increased by 2°C and 7.8-folds, respectively. Molecular dynamics simulation showed reduced flexibility and additional chemical bonds in the region near the mutation site.

Discussion

These results indicate that we obtained a Anman mutant that is more suitable for industrial application, and they also confirm that a combination of rational and semi-rational techniques is helpful for screening mutant sites.

[Low-dose helical CT projection data restoration using noise estimation]

OBJECTIVE

To build a helical CT projection data restoration model at random low-dose levels.

METHODS

We used a noise estimation module to achieve noise estimation and obtained a low-dose projection noise variance map, which was used to guide projection data recovery by the projection data restoration module. A filtering back-projection algorithm (FBP) was finally used to reconstruct the images. The 3D wavelet group residual dense network (3DWGRDN) was adopted to build the network architecture of the noise estimation and projection data restoration module using asymmetric loss and total variational regularization. For validation of the model, 1/10 and 1/15 of normal dose helical CT images were restored using the proposed model and 3 other restoration models (IRLNet, REDCNN and MWResNet), and the results were visually and quantitatively compared.

RESULTS

Quantitative comparisons of the restored images showed that the proposed helical CT projection data restoration model increased the structural similarity index by 5.79% to 17.46% compared with the other restoration algorithms (P < 0.05). The image quality scores of the proposed method rated by clinical radiologists ranged from 7.19% to 17.38%, significantly higher than the other restoration algorithms (P < 0.05).

CONCLUSION

The proposed method can effectively suppress noises and reduce artifacts in the projection data at different low-dose levels while preserving the integrity of the edges and fine details of the reconstructed CT images.

[An adaptive CT metal artifact reduction algorithm that combines projection interpolation and physical correction]

OBJECTIVE

To propose an adaptive weighted CT metal artifact reduce algorithm that combines projection interpolation and physical correction.

METHODS

A normalized metal projection interpolation algorithm was used to obtain the initial corrected projection data. A metal physical correction model was then introduced to obtain the physically corrected projection data. To verify the effectiveness of the method, we conducted experiments using simulation data and clinical data. For the simulation data, the quantitative indicators PSNR and SSIM were used for evaluation, while for the clinical data, the resultant images were evaluated by imaging experts to compare the artifact-reducing performance of different methods.

RESULTS

For the simulation data, the proposed method improved the PSNR value by at least 0.2 dB and resulted in the highest SSIM value among the methods for comparison. The experiment with the clinical data showed that the imaging experts gave the highest scores of 3.616±0.338 (in a 5-point scale) to the images processed using the proposed method, which had significant better artifact-reducing performance than the other methods (P < 0.001).

CONCLUSION

The metal artifact reduction algorithm proposed herein can effectively reduce metal artifacts while preserving the tissue structure information and reducing the generation of new artifacts.

Preparation of Zr/Y co-doped TiO2 photocatalyst and degradation performance of hydroquinone

In this paper, Y-ZrO₂-TiO₂ photocatalyst was prepared by sol-gel method, the titanium source was tetrabutyl titanate, and the precursors were zirconium nitrate pentahydrate and yttrium nitrate hexahydrate. For the photocatalytic effect of Y-ZrO₂-TiO₂ to hydroquinone, these effects were investigated: doping ratios of Zr/Y, calcination conditions, pH, etc. And the materials were characterized by XRD, TEM-EDS, XPS, PL, ESR, etc. The results showed that the optimum preparation conditions of Y-ZrO₂-TiO₂ photocatalyst were as follows: the molar ratio of doping was Ti: Zr: Y = 100:6:0.5, the calcination temperature was 500 °C, and the calcination time was 2 h; the optimum reaction conditions were as follows: the dosage of Y-ZrO₂-TiO₂ was 1 g/L, and pH value was 6.96. The degradation rate of hydroquinone under 365-nm UV lamp for 50 min could reach 96.58%, while the degradation rates of pure TiO₂, Y-TiO₂, and ZrO₂-TiO₂ under the same conditions were 33.95%, 79.55%, and 90.30%, respectively. It can be seen that the addition of elements Zr and Y improves the photocatalytic performance of TiO₂.

One-step fabrication of novel MIL-53(Fe, Al) for synergistic adsorption-photocatalytic degradation of tetracycline

Bimetallic MOFs (MIL-53 (Fe, Al)) were successfully fabricated via a facile one-step solvothermal method for the removal of tetracycline (TC) from aqueous solutions. Tetracycline adsorption and photocatalytic experiments indicate that the optimum bimetallic synthetic molar ratio is 3:2 (40%MIL-53(Fe, Al)). The adsorption data are well fitted by the Freundlich model and pseudo-second-order adsorption kinetics. 40%MIL-53(Fe, Al) has an adsorption capacity of up to 402.033 mg/g. After the dark adsorption phase, 10 mg of 40%MIL-53(Fe, Al) can remove 94.33% of the tetracycline in a 70 mL aqueous solution (20 mg/L) under 50 min irradiation, while only 71.39% and 81.82% of the tetracycline are removed by MIL-53(Fe) and MIL-53(Al) under the same conditions. In addition, 40%MIL-53(Fe, Al) exhibits a significant adsorption-photocatalytic synergy (under direct irradiation without a dark adsorption phase), in which the pseudo-first-order kinetic constant increases by a factor of 3.11. Quenching experiments and ESR characterization indicate that ·O₂^-, ·OH, and h⁺ are the main active species in the photocatalytic process. Meanwhile, 40%MIL-53(Fe, Al) demonstrates good stability, with a tetracycline removal rate that still reaches 83.70% after 4 cycles. These results suggest that the prepared 40%MIL-53(Fe, Al) catalyst is a novel adsorption-photocatalytic material that can be used for the efficient treatment of tetracycline.

[Molecular characterization of Staphylococcus aureus ST6 and ST7 isolates from food-borne illness outbreaks]

Objective: To analyze the Staphylococcal enterotoxins, Staphylococcal enterotoxin genes, drug resistance and molecular typing of 41 Staphylococcus aureus isolates from 2 food-borne illness outbreaks on 21 August and 27 September 2020 in Guangzhou. Methods: A total of 41 Staphylococcus aureus isolates from 2 outbreaks were analyzed by multilocus sequence typing (MLST) and spa typing. The Staphylococcal enterotoxins typing and the Staphylococcal enterotoxin genes of the isolates were analyzed by ELISA and PCR, respectively. The antimicrobial susceptibility of the isolates was performed by disc diffusion. 21 Staphylococcus aureus isolates were characterized using whole genome sequencing (WGS). Based on the whole genome single nucleotide polymorphism (SNP), the phylogenetic tree was constructed by Snippy. Results: 41 Staphylococcus aureus isolates were divided into 2 types by MLST and spa typing: ST6-t701 and ST7-t091. 2 ST7-t091 isolates were identified as methicillin-resistant Staphylococcus aureus (MRSA). 25 ST7-t091 isolates and 14 ST6-t701 isolates were methicillin-sensitive Staphylococcus aureus (MSSA), and were resistant to 7 and 6 antibiotics, respectively. All isolates were positive for sea by PCR. WGS revealed all 21 isolates carried scn, sak, sea, hla, hld, hlgA, hlgB, hlgC, lukD virulence genes. The results showed the isolates contained an immune evasion cluster type D which located in bacteriophage ϕSa3. The SNP phylogenetic tree showed 2 MRSA ST7-t091 were constituted a separate clade from the 12 MSSA ST7-t091 isolates and 7 ST6-t701 isolates showed high similarity to each other. Conclusion: Base on the results of phylogenetic analysis, the 2 food-borne illness outbreaks occurred on 21 August and 27 September 2020 are caused by the combination of the MRSA ST7-t091 strain and the MSSA ST7-t091 strain, and the MSSA ST6-t701 strain, respectively. All isolates have high level of antibiotic resistance and carry high virulent genes.

[Identification of traditional Chinese drugs containing active ingredients for treating myocardial infarction and analysis of their therapeutic mechanisms by network pharmacology and molecular docking]

OBJECTIVE

To identify traditional Chinese drugs that contain active ingredients for treatment of myocardial infarction (MI) and explore their therapeutic mechanisms using network pharmacology and molecular docking technology.

METHODS

The TCMSP database was used for screening the traditional Chinese drugs containing active ingredients for treating MI, and the related targets of MI and the candidate drugs were obtained from Genecards, OMIM, PharmGkb and PharmMapper databases. The common target network of the drug targets and disease targets was established using Venny2.1.0 software. GO and KEGG signal pathway enrichment analysis of the common targets was performed, and the protein-protein interaction (PPI) network was constructed for the targets. The targets in the PPI network were analyzed to identify the key targets, for which GO and KEGG pathway enrichment analyses were performed. Molecular docking was performed for the candidate ingredients and the key targets, and a total score ≥6 was used as the criteria for screening the therapeutic ingredients and their docking binding with key targets was verified. A human umbilical vein endothelial cell (HUVEC) model of oxygen-glucose deprivation (OGD) was used to validate the candidate ingredients and the key therapeutic targets for MI by Western blotting.

RESULTS

Our analysis identified Salvia miltiorrhiza and Dalbergiae odoriferae as the candidate drugs rich in active ingredients for treatment of MI. These ingredients involved 16 key therapeutic targets for MI, which participated in such biological processes as inflammatory response, angiogenesis, energy metabolism and oxidative stress and the pathways including HIF-1, VEGF, and TNF pathways. Sclareol and PTGS2 in Salvia miltiorrhiza and formononetin and KDR in Dalbergiae odoriferae all had high docking total scores. Western blotting showed that at medium and high doses, sclareol significantly inhibited PTGS2 expression and formononetin promoted KDR expressions in the cell models in a dose-dependent manner (P < 0.05).

CONCLUSION

Both Salvia miltiorrhiza and Dalbergiae odoriferae have good therapeutic effects on MI. Sclareol in Salvia miltiorrhiza and formononetin in Dalbergiae odoriferae regulate the expressions of KDR and PTGS2, respectively, to modulate the inflammatory response, angiogenesis, oxidative stress and energy metabolism and thus produce myocardial protective effects.

Materials in advanced design of personal protective equipment: a review

The outbreak of the Covid-19 pandemic has aroused tremendous attention toward personal protective equipment (PPE) in both scientific research and industrial manufacture. Despite decades of development in PPE design and fabrication, there's still much room for further optimization, in terms, of both protection performance and wear comfort. Interdisciplinary efforts have been devoted to this research field in recent years. Significantly, the innovation of materials, which brings about improved performance and versatile new functions for PPEs, has been widely adopted in PPE design. In this minireview, recent progress in the development of novel materials and structural designs for PPE application are presented in detail with the introduction of various material-based strategies for different PPE types, as well as the examples, which apply auxiliary components into face masks to enrich the functionalities and improve the personal feelings in the pandemic period.

[Mid-and-long term follow-up of autogenous tibial periosteum-bone complex transplantation for treatment of cystic osteochondral lesion of talus]

Objective: To further clarify the mid-and-long term follow-up results of self-designed tibial periosteum-bone complex transplantation in the treatment of Hepple V osteochondral lesion of the talus(OLTs). Methods: The clinical data of 30 patients with Hepple V OLTs who received treatment in the Sports Medicine Center of the First Affiliated Hospital of Army Military Medical University from October 2011 to January 2019 were analyzed. There were 19 males and 11 females with a mean age of (40±11) years. Patients were treated with autogenous tibial periosteum-bone complex transplantation and were followed up for at least 2 years. The Foot and Ankle Outcome Score (FAOS), American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the visual analog scale score (VAS) of pain, the simplified symptomatology evaluation (SSE) and imaging results before the operation and at the follow-up were recorded and compared. Results: The cohort were followed-up for a mean of 63.9 months (range 24-110 months). Twenty-nine (96.7%) patients were satisfied with the curative effect. The FAOS score was improved from 53.5±6.2 preoperatively to 88.4±6.6 at the final follow-up (P<0.001). The AOFAS ankle-hindfoot scale improved from 61.6±8.2 preoperatively to 90.8±6.8 at the last follow-up (P<0.001). The VAS score decreased from 4.3±0.2 preoperative to 0.7±0.7 at the last follow-up (P<0.001). The SSE score was poor in 14 cases (46.7%), average in 16 cases (53.3%) before the operation; and it was excellent in 23 cases (76.7%), good in 6 cases (20%), average in 1 case (3.3%) at the last follow-up. Imaging examination showed cystic change cure rate was 83.3%, cartilage defects were completely infilled with repair tissue, which didn't show any signs of degeneration. However, repair tissue showed varying degrees of heterogeneous signal compared to the normal articular cartilage. Conclusion: The autograft of tibial periosteum-bone complex transplantation is a safe and feasible method for the treatment of osteochondral lesion of the talus in Hepple V type, with good mid-and-long term clinical effect.

[Risk stratified management of cervical adenocarcinoma in situ based on cone margin state]

Objective: To investigate the hierarchical management scheme of cervical adenocarcinoma in situ (AIS) based on cervical conization margin state. Methods: All medical records of 249 patients diagnosed as AIS by loop electrosurgical excision procedure (LEEP) conization from Jan. 2010 to Dec. 2015 in Obstetrics and Gynecology Hospital of Fudan University were retrospectively reviewed, to explore the relationship between the status of the resection margin and the residual lesion after LEEP, and the multivariate logistic regression method was used to analyze the related factors that affect the residual lesion after LEEP in cervical AIS patients. Results: (1) The age of 249 cervical AIS patients was (40±8) years old (range: 23-71 years old). Of the 249 patients, 19 (7.6%, 19/249) had residual lesions; 69 cases were pathologically diagnosed as AIS after LEEP, and the residual lesion rate was 13.0% (9/69), which was significantly higher than that of AIS + high-grade squamous intraepithelial lesion [5.6% (10/180); χ²=3.968,P=0.046]; 33 cases were multifocal lesions, the residual rate of lesions was 21.2% (7/33), which was significantly higher than that of single focal lesions patients [5.6% (12/216); χ²=7.858, P=0.005]; 181 patients underwent endocervical curettage (ECC) before surgery, the residual rate of lesions in ECC-positive patients was 14.0% (14/100) , significantly higher than that of ECC-negative patients [4.9% (4/81); χ²=4.103, P=0.043]. (2) Among 249 cases of AIS patients, the positive rate of resection margins after LEEP was 35.3% (88/249); the residual rate of lesions in patients with positive resection margins (14.8%, 13/88) was significantly higher than those with negative margins [3.8%(6/156); χ²=9.355, P=0.002]. The age of patients underwent total hysterectomy after LEEP was (43±7) years old, which was significantly higher than that of patients who did not undergo total hysterectomy [(37±8) years old; t=6.518, P<0.01].Among the patients underwent total hysterectomy after LEEP, 3 cases (2.0%, 3/152) had fertility requirements, while 38 cases (39.2%, 38/97) did not underwent total hysterectomy, the difference between the two groups was statistically significant (χ²=59.579, P<0.01). Among the 152 patients who underwent total hysterectomy after LEEP, the residual rate of lesions was 11.8% (18/152); the residual rate of lesions in patients with positive resection margins was significantly higher than that of patients with negative resection margins [18.8% (12/64) vs 7.0% (6/86); χ²=4.861, P=0.028]. The median follow-up time of 97 patients who did not undergo total hysterectomy after LEEP was 32 months (range: 4-70 months). During the follow-up period, 3 cases of cervical AIS recurrence (3.1%, 3/97) and were followed by hysterectomy,no invasive adenocarcinoma were seen. (3) Multivariate logistic regression analysis showed that the positive resection margin (OR=4.098, 95%CI: 1.235-13.595, P=0.021), multifocal lesions (OR=5.464, 95%CI: 1.494-19.981, P=0.010) were independent risk factors that affected the residual lesions in patients with cervical AIS after LEEP. Conclusions: The cervical AIS patients after LEEP conization suggested be stratified by cone margin state as the first-line stratified index, age and fertility needs as the second-line stratified management index. The individualized management plan should be developed based on comprehensive assessment of high-risk factors of residual lesions.

P–563 Assessing ovarian age: Could we use leukocyte telomere length as a surrogate marker of cumulus cells telomere content?

Study question

Is leukocyte telomere length (LTL) correlated with cumulus cells telomere length (CCTL) in an age-heterogeneous women population?

Summary answer

LTL showed a positive correlation with CCTL in the studied population. Hence, its potential value as indicator of ovarian age would deserve further evaluation.

What is known already

Progressive telomere shortening has been related to ovarian aging and genomic instability during early development. A positive correlation between short telomere length of the first polar body and aneuploidy rate has been reported. CCTL has shown to be a biomarker of oocyte and embryo quality, but its assessment is impractical. LTL has been proposed as a surrogate of TL of follicular cells, but telomere lengthening through folliculogenesis could be controlled by different mechanisms. Thus, we aimed to determine if LTL in an age-heterogeneous population is correlated with CCTL and therefore considered an accurate surrogate for telomere length in the ovary.

Study design, size, duration

In this prospective non-interventional cohort study, 35 egg donors and 17 women undergoing Preimplantation Genetic Testing for Aneuploidy (PGT-A) treatment were included during sixteen months. Following controlled ovarian stimulation determined by treating physicians, oocyte retrieval was performed 36 hours after final maturation induction. Cumulus cells (CC) for telomere length (TL) measurement were obtained after the pick-up and oocyte stripping. A blood sample was collected through peripheral venous access for LTL measurement.

Participants/materials, setting, methods

Genomic DNA of CC and leukocytes from the 52 subjects was isolated. Average delta cycle threshold (ΔCt) was determined using a SYBR green quantitative real-time PCR protocol for relative TL. For normalization of measurements, a Taqman assay for the multicopy gene Alu was performed. ΔCtL and ΔCtCC were compared by a paired t-test analysis and the fold change was calculated. Additionally, the association between them and patient age was analyzed by a Pearson correlation test.

Main results and the role of chance

Mean participant’s age was 29.94 ± 7.55 years and mean values for ΔCtL and ΔCtCC were 7.99 ± 0.53 and 7.46 ± 0.75, respectively. A positive significant correlation was found between age and ΔCt (ΔCtL: R2=0.71, p-value=5.18e–09; ΔCtCC: R2=0.47, p-value=0.00049). Since ΔCt values are inversely proportional to the amount of nucleic acids amplified and, therefore, to the telomere length, this correlation means that TL in both cell types decreases as women age. Additionally, ΔCtL was significantly higher than ΔCtCC (ΔCt fold change: 0.93, p-value=9e–07), meaning that CC showed significantly longer telomeres than leukocytes, thus supporting our previous published results in young egg donors. When analyzing the ΔCtL and ΔCtCC in these age-heterogeneous sample, a positive moderate and significant correlation was observed (R2=0.42, p-value=0.002). Thus, LTL could be suggested as a potential indicator of CCTL and therefore as a candidate for a biological marker of ovarian aging.

Limitations, reasons for caution

The sample size of this study was moderate and perhaps increasing the number of subjects might give additional strength to our findings. In addition, although relative telomere length allowed for adequate comparison between subjects, this method did not allow for absolute TL measurement.

Wider implications of the findings: While reproductive implications of LTL measurement need to be further studied, our results support the potential usefulness of LTL measurement as an indicator of CCTL and ovarian aging when analyzing an age-heterogeneous population. Further, our findings suggest that CC could possess different mechanisms to cope against telomere length shortening.

Trial registration number

Not applicable

Evaluation of the photocatalytic performance of molecularly imprinted S-TiO2 by paper microzones

The paper microzones method (PMZs) is a green chemical method that uses the principle of the three primary colors of red, green and blue (RGB) to detect the water quality of the droplets on white paper. However, this method is rarely used in the performance evaluation of photocatalysts. The paper details the first use of paper microzones utilized in the evaluation of photocatalyst performance. A sol-gel method was used to prepare molecularly imprinted modified TiO₂ photocatalysts for the treatment of different wastewaters, and characterized the catalysts using XRD and several other methods. The reliability of PMZs on the evaluation of photocatalytic activity and selectivity was also analyzed. The following results were obtained: EP-TiO₂ catalysts (EP, ethyl paraben, the imprinting molecule) with different S doping levels were synthesized using a one-step sol-gel method, and the best S doping ratio was found to be n(Ti):n(S) 3:1. S-EP-TiO₂ was found to be 100% anatase and showed excellent photocatalytic performance, while the PMZs method accurately determined changes in RGB levels for the photocatalytic degradation process of pollutants using S-EP-TiO₂ as the photocatalyst. A photocatalytic kinetic analysis showed the PMZs method was quite suitable for the evaluation of photocatalyst activity, but the evaluation of selectivity needs improvement. This method is a promising green chemistry way to evaluate photocatalyst performance and the rapid detection of outdoor sewage water quality.

Comparison of long non-coding RNAs in adipose and muscle tissues between seven indigenous Chinese and the Yorkshire pig breeds

lncRNAs play crucial roles in fat metabolism in animals. Previously, we have compared the mRNA transcriptome profiles between seven fat-type Chinese pig breeds and one lean-type Western breed (Yorkshire, YY). The associations between differentially expressed (DE) genes and phenotypical traits were investigated. In the present study, to further explore the underlying regulatory mechanisms, lncRNAs were sequenced and compared between YY and Chinese indigenous breeds. The results showed 9114 and 7538 DE lncRNAs between at least one Chinese breed and the YY breed in the adipose and muscle tissue respectively. KEGG enrichment analysis revealed that the target genes of these DE lncRNAs mainly influenced the glucolipid metabolism, which is an important process affecting meat quality. Correlation analyses between the DE lncRNA and DE mRNA genes related to meat quality and growth traits were performed. The results showed that LTCONS_00073280 was associated with intramuscular fat content. Four lncRNAs (LTCONS_00101781, LTCONS_00037879, LTCONS_00088260 and LTCONS-00128343) might mediate backfat thickness. Overall, this study provides candidate lncRNAs that potentially affect meat quality, which might be useful for molecular breeding of pig breeds in future.

[Early clinical efficacy analysis of personalized three-dimensional printing talus prosthesis in the treatment of collapse talus necrosis]

Object To examine the preliminary clinical efficacy of custom-made three-dimensional(3D) printed talus prosthesis in the treatment of collapse talus necrosis. Methods: The clinical data of 8 patients who received 3D printed custom-made talus prostheses replacement for severe collapsed necrosis of the talus at the Orthopaedic Sports Medical Center, the First Affiliated Hospital to Army Medical University were analyzed retrospectively.All patients were male,with an average age of 38.0 years (range:22 to 65 years).There were 5 cases of left talus collapse and 3 cases of right talus collapse,with the course of disease of 29.7 weeks (range:6 to 96 weeks).The CT data of contralateral healthy talus were used for mirror image design references for the prosthesis,and the electron-beam 3D printing technology was used to prepare the prosthesis.Titanium alloy (Ti6Al4V) was taken as the material for the preparation of the talus body prosthesis,and Co-Cr-Mo material was used as the material for the preparation of the tibialis talus lateral joint surface prosthesis,and the subtalar joint surface of the prosthesis was made from a microporous casting technique.The prosthesis was analyzed preoperatively by digital three-dimensional finite element analysis and solid comparison techniques to measure anatomic match of the prosthesis.A longitudinal incision on medial ankle was made.The necrotic talus was completely removed and the prosthesis was then implanted.The patient was reexamined in the outpatient department 3, 6, and 12 months after surgery.Primary outcome measures were the American Orthopaedic Foot and Ankle Society(AOFAS) ankle-hind foot score,visual analogue scale(VAS) and ankle range of motion.Changes in imaging data and plantar pressure were also assessed.Repeated measures analysis of variance and paired-t test were used to compare the data. Results: The talus prosthesis measure preoperatively was completely consistent with that contralateral healthy talus and there was no operation-related complication. All the wounds healed primarily. The patients were followed up effectively for 23.17 months (range:12 to 48 months).The preoperative dorsiflexion of patients was (7.6±5.7)°,it increased to(14.2±6.6)° at 12 month after surgery (t=-2.67,P=0.03).The plantar flexion increased from (22.0±9.9)°preoperatively to (29.2±8.7)° at 12 month after surgery (t=-8.95,P<0.01).Preoperative AOFAS ankle-hind foot score was 26.3±6.6,and it increased to 70.1±2.2,76.0±3.4 and 79.3±4.2 at 3 month,6 month and 12 month after surgery(F=56.81,P<0.01);Pre-operative VAS was[M(Q_R)]3.0(0.8),and it increased to 2.5(1.0),1.5(1.0),1.0(1.0)at 3 month,6 month and 12 month after surgery(F=20.00,P<0.01).At the last follow-up,imaging reexamination showed that the prosthesis of all patients were in stable position with no sign of subsidence.No secondary ankle fusion or revision was required.The talus height increased from (27.6±6.0)mm preoperatively to (34.6±3.5)mm (t=-2.94,P<0.01).The plantar pressure showed that the maximum pressure on the healthy ankle was(629.9±26.1)N,and that on the affected side was(521.4±14.4)N.The pressure on the healthy ankle was(350.6±29.6)N,and that on the necrotic side was (212.3±9.7)N.The load on the contralateral forefoot was(38.1±2.8)% and that on the necrotic side was(11.5±2.0)%.The load on the contralateral hindfoot was (24.6±2.5)% and that on the necrotic side was (21.1±1.8)%. Conclusions: The custom-made 3D printed talus prosthesis could restore the talus anatomy,recover the ankle joint function,relieve the pain of patients and improve the life quality of patients.The effect on plantar pressure is mainly achieved by adjusting the center of gravity of plantar pressure backwards and the increase of weight bearing of the healthy foot.

[Clinicopathological features of adenocarcinoma of the rete testis]

Objective: To investigate the clinicopathological features, immunophenotype, and differential diagnosis of adenocarcinoma of the rete testis. Methods: Four adenocarcinoma cases of the rete testis diagnosed at West China Hospital, Chengdu, China (3 cases, including 2 consultation cases) and the First Affiliated Hospital of Fujian Medical University, Fuzhou, China (1 case) between January 2009 and December 2017 were included. Their clinical, morphologic and immunohistochemical features were analyzed using histological analysis and immunohistochemical staining. Related literature was reviewed to reveal the characteristics of this tumor. Results: The 4 patients' age range was 26-64 years. The maximum diameters of the tumors were 3.0 and 4.5 cm in 2 cases, respectively. On gross examination, adenocarcinomas of the rete testis appeared as a solid, white to gray or tan to yellow mass that raised at the hilum of the testis. Microscopically, all tumors showed multiple histologic patterns, including corded/trabecular (4/4), glandular, nested, sarcomatoid (3/4), solid (2/4), papillary, cribriform, and slit-like (1/4). Three types of adenocarcinoma cells included cuboidal to columnar (4/4), polygonal (4/4) and spindle-shaped (2/4) with pale eosinophilic and clear cytoplasm. The tumor cell nuclei appeared moderately to markedly atypical and pleomorphic, with a various number of mitoses. Transition from benign to malignant rete epithelium was seen in all cases. Eosinophilic hyaloid globules were found in 1 case. On immunohistochemical study, the tumor cells were diffusely, strongly positive for CKpan (4/4), EMA (4/4), Ber-EP4 (3/3) and CAⅨ(2/2), and focally positive for CK7 (4/4), vimentin (4/4), CD10 (4/4), PAX8 (3/3), PAX2 (3/3). The Ki-67 proliferative index was all>50% (4/4). The prognosis was poor. Two of the 3 patients died within 1 year after the surgical resection. Conclusions: Adenocarcinoma of the rete testis is a rare malignant tumor with several histologic patterns. Transition from benign to malignant rete epithelium is an important diagnostic clue. Detailed clinical history, tumor growth site and immunohistochemistry are helpful for its diagnosis and differential diagnosis.

Contributions of epiphytic microbiota on the fermentation characteristics and microbial composition of ensiled six whole crop corn varieties

AIMS

The present study is aimed to reveal the variations in epiphytic microbial composition among six whole crop corn (WCC) varieties and their contributions on ensiling characteristics and microbial composition of WCC silage.

METHODS AND RESULTS

Six WCC varieties (JS06, YS23, BS20, JS39, JS40 and JS26) were ensiled for 90 days. All WCC varieties were well fermented with low pH value (<4·0) and high LA (73·6-124 g kg^-1 DM, dry matter) concentration. Of six varieties, JS40 had the highest LA (124 g kg^-1 DM) concentration, which was supported by highest relative abundance of Lactobacillus. Pantoea was the most dominant epiphytic bacteria in all fresh WCC varieties; however, the secondary dominant genera among six WCC were absolutely difference. Lactobacillus became predominant genus in 90-day silages except YS23. YS23 kept the more bacterial genus from fresh to 90-day silages than other silages, meanwhile Acinetobacter and Enterobacter were the dominant bacteria in YS23 silages.

CONCLUSIONS

Among six WCC varieties, JS40 silage had the highest LA. The variations in epiphytic microbiomes among fresh WCC affected terminal microbial community of 90-day silages. There were differences in fermentation characteristics among six WCC varieties, which might be partly attributed to variations in epiphytic microbiomes among fresh WCC.

SIGNIFICANCE AND IMPACT OF THE STUDY

The study not only enriches the research on microbial communities of plant phyllosphere but also provides theoretical basis for selecting WCC varieties and inoculants for the forage production.

Characterization and identification of cellulase-producing Enterococcus species isolated from Tibetan yak (Bos grunniens) rumen and their application in various forage silages

AIMS

Cellulase-producing Enterococcus species isolated from the rumen of Tibetan yak (Bos grunniens) were characterized, and their combined effects on the silage quality of various forages were studied.

METHODS AND RESULTS

The two isolated strains with high cellulolytic potential were identified as Enterococcus faecalis (EF85) and E. faecium (EF83) by 16S rRNA sequencing. Both EF85 and EF83 could grow well at 15-55°C, pH 3·0-6·0 and in 3·0-6·5% NaCl. The cellulase secreted by EF85 and EF83 showed good stability at temperatures from 20 to 45°C and pH from 4·5 to 7·0. A commercial inoculant (CLP), a commercial cellulase (CE) and the two cellulolytic strains (EF85 + EF83) were added to whole-crop corn, sweet sorghum and Napier grass ensiling for 120 days respectively. In Napier grass silage, all inoculants significantly increased lactic acid content and ratio of lactic to acetic acid and decreased pH, butyric acid and ammonia nitrogen contents. The acid detergent fibre and cellulose contents in EF85 + EF83 treatment were significantly lower than those in the other treatments. In whole-crop corn and sweet sorghum silages, all additives had no significant effect on the fermentation quality, while CE and EF85 + EF83 markedly enhanced cellulose degradation and increased free sugar content.

CONCLUSION

The combined inoculation of the cellulolytic strain EF85 and EF83 to various forages reduced the fibre content of the resulting silages.

SIGNIFICANCE AND IMPACT OF THE STUDY

Few studies involved inoculation of silage with Enterococcus species in different forage types. The isolated cellulolytic strains of E. faecalis EF85 and E. faecium EF83 could be a great alternative for commercial inoculants and enzymes in silage production.

[Study on the clinical significance and correlation of arginase-1 and inducible nitric oxide synthase expression in hepatocellular carcinoma]

Objective: To investigate the clinical significance and correlation of arginase 1 (Arg-1) and inducible nitric oxide synthase (iNOS) expression in hepatocellular carcinoma (HCC). Methods: The expression of Arg-1and iNOS in 146 cases of hepatocellular carcinoma tissues and corresponding adjacent tissues was detected by immunohistochemistry. The clinicopathological characteristics and the correlation between the expressions and prognosis were determined by chi square test, Spearman's rank correlation, Kaplan-Meier survival analysis and Cox regression analysis. Results: The positive rates of Arg-1 and iNOS were 18.7% (23/123) and 37.0% (54/146), respectively, which was significantly lower than the adjacent tissues [100%(146/146) and 93.8% (137/146)] and the difference was statistically significant (χ (2) = 212.521, P < 0.01, χ (2) = 104.276, P < 0.01). There was a positive correlation between the both expression (r = 0.331, P < 0.01). Arg-1 low expression was correlated with preoperative serum alpha-fetoprotein (AFP) level, tumor size, differentiation degree, histological types and Edmondson's grade. iNOS low expression was correlated with the differentiation degree and Edmondson's grade (P < 0.05). Kaplan Meier survival analysis showed that in patients with recurrence-free survival (RFs), Arg-1 (+) group > Arg-1 (-) group and Arg-1 (+) iNOS (+) group > Arg-1 (+) iNOS (-) group > Arg-1 (-) iNOS (-) group (P < 0.05). Cox multivariate analysis showed that age, tumor size, Edmondson's grade, vascular tumor emboli were significantly correlated with RFs (P < 0.05). Conclusion: There is a positive correlation between Arg-1 and iNOS expressions in HCC, and both may reflect the HCC malignant degree. The reduced/absent expression of both may participate in the occurrence and development of HCC. The combined detection of Arg-1 and iNOS on HCC may have certain significance for the judgment of differentiation degree and prognosis.

Protective effects of Lactobacillus plantarum strain P1 against toxicity of the environmental oestrogen di-n-butyl phthalate in rats

Phthalates are contaminants widely distributed in the food-chain, and they are considered as important environmental oestrogens in our lives. In the present study, eight strains of lactic acid bacteria were isolated for their ability to adsorb di-n-butyl-phthalate (DBP), and one of the strains, Lactobacillus plantarum strain P1, was selected for more detailed analyses of its phthalate adsorption capacity in vitro. This study also evaluated the in vivo protective effects of strain P1 against DBP toxicity in rats. Sixteen rats were divided into four groups, and animals received by oral gavage every other day for a period of one month saline with or without strain P1 at 2×10¹¹ cfu/kg followed by maize oil with or without DBP (50 mg/kg). Strain P1 could adsorb more DBP than saline alone, and the concentration of mono-n-butyl phthalate in urine was decreased in animals receiving P1. Furthermore, oestrogenic effects of the different treatments were assessed through counting of sperm and observation of testis, and strain P1 could protect the sexual organs of male rats. Our results suggested that P1 is effective against phthalate toxicity due to its ability to adsorb DBP in vivo and could be considered as a new dietary therapeutic strategy against environmental phtalate toxicity.

Effect of sorbic acid and dual-purpose inoculants on the fermentation quality and aerobic stability of high dry matter rice straw silage

AIMS

This study aimed to evaluate the feasibility of sorbic acid (SA) as a silage additive and its effects on fermentation quality and aerobic stability of high dry matter (DM) silage.

METHODS AND RESULTS

High DM rice straw was ensiled with distilled water (C), 1 × 10⁶  CFU per gram fresh weight (FW) Lactobacillus plantarum and 1 × 10⁶  CFU per gram FW Lactobacillus buchneri (LP+LB) or SA for 45 days with a subsequent aerobic stability test. After ensiling, LP+LB silage had the highest lactic acid (LA) content and the lowest pH value, whereas SA silage had the highest DM and water-soluble carbohydrate (WSC) contents, and the lowest ethanol and ammonia nitrogen (NH₃ -N) contents among all silages (P < 0·001). Compared to C silage, SA significantly (P < 0·01) reduced the counts of yeasts but not lactic acid bacteria (LAB). During 6-day aerobic exposure, the continuous pH increase and LA decrease were observed in C and LP+LB silages, and there was no significant change in pH, DM, NH₃ -N and WSC contents of SA silage over the whole aerobic exposure. The SA addition slowed the decline of LA and acetic acid (AA) contents as well as the growth of yeasts and aerobic bacteria under aerobic exposure.

CONCLUSION

In this study, L. buchneri could not function in high DM rice straw silage while SA effectively improved both the fermentation quality and aerobic stability.

SIGNIFICANCE AND IMPACT OF THE STUDY

The SA was more effective than dual-purpose inoculants to improve the aerobic stability of high DM rice straw silage. Thus, SA can be served as a potential antifungal additive for silage with high DM.

Ultra-small-size Astragaloside-IV loaded lipid nanocapsules eye drops for the effective management of dry age-related macular degeneration

Background Age-related macular degeneration (AMD) is a major cause of severe visual loss in elderly people. The treatments for dry AMD (dAMD) are severely limited so far. In this work, we aim to develop an eye drop to protect retinal functions against oxidative stress and apoptosis for improving dAMD management. Methods Astragaloside-IV (ASIV) was prepared into phospholipid complex and loaded into three sizes (20, 50 and 90 nm) of ASIV lipid nanocapsules (ASIV-LNCs). The penetration and distribution of LNCs were investigated. DAMD mice model was induced by NaIO₃, and therapeutic effect was evaluated by electroretinography (ERG), histological examination, apoptosis and ROS detection. Results The ocular penetration and pharmacokinetic studies corroborated the feasibility of the LNCs to reach the fundus, and ultra-small-size LNCs (ASIV-LNCs-20) had the best delivery effect. ASIV-LNCs-20 was able to decrease ROS production and reduce the apoptosis rate from 5.12% to 0.533%. ERG and H&E staining results confirmed ASIV-LNCs-20 had a good protective effect on the morphology and function of the retina. Conclusions These results suggest that ASIV-LNCs can be a promising therapy approach for dAMD, and this research also offers new possibilities for further applications of LNCs as a drug delivery system for other eye diseases. Abbreviations AMD: Age-related macular degeneration;AREDS Age-related eye disease study; ASIV: Astragaloside-IV;AUC: Area under the concentration-time curve; dAMD: Dry age-related macular degeneration; DHE: Dihydroethidium; DL: Drug Loading; DLS: Dynamic light scattering; DSC: Differential scanning calorimetry; EE: Entrapment efficiency; ELSD: Evaporative light scattering detector; ERG: Electroretinographic; H&E: Hematoxylin and Eosin; I.S.: Internal standard; LB: Langmuir-Blodgett; LNCs: Lipid nanocapsules; MCT: Medium-chain triacylglycerol; ONL: Outer nuclear layer; OPL: Outer plexiform layer; PDI: Polydispersity index; PR: Photoreceptor;ROS: Reactive oxygen species; RPE: Retinal pigment epithelium; TEM: Transmission electron microscope; wAMD: Wet age-related macular degeneration.

Childhood COVID-19: a multicentre retrospective study

Objectives

To investigate the clinical and epidemiological characteristics of paediatric patients with coronavirus disease-19 (COVID-19).

Methods

Paediatric patients diagnosed with COVID-19 between January 15 and March 15, 2020, from seven hospitals in Zhejiang Province, China, were collected retrospectively and analysed.

Results

Thirty-two children with COVID-19, ranging in age from 3 months to 18 years, were enrolled. Family aggregation occurred in 87.5% of infant and preschool-aged children (7/8), and also school-aged children (14/16), but in only 12.5% (1/8) of adolescents (p < 0.05, p < 0.001). Most of these patients had mild symptoms: mainly fever (20/32) followed by cough (10/32) and fatigue (4/32). The average durations of viral RNA in respiratory samples and gastrointestinal samples were 15.8 d and 28.9 d, respectively. Detox duration in faeces decreased with age: 39.8 d, 27.5 d and 20.4 d in infants and preschool children, school children, and adolescents respectively (p_{0–6, –18} <0.01, p_{0–6, –14} <0.05). Pneumonia was found in 14 children, but there was no statistical significance in the incidence of pneumonia between different age groups. Thirty patients were treated with antiviral drugs, and all patients were stable and gradually improved after admission.

Conclusions

Most children with COVID-19 had a mild process and a good prognosis. More attention should be paid to investigation of household contact history in the diagnosis of COVID-19 in young children. Viral RNA lasts longer in the gastrointestinal system than in the respiratory tract, especially in younger children.

THU0544 MULTIMODAL PHOTOACOUSTIC/ULTRASONIC IMAGING SYSTEM: A NEW IMAGING METHOD FOR EVALUATING RA

Background:

Photoacoustic imaging (PAI), a new imaging technique which can be integrating with ultrasound (US) imaging, has shown potential in visualizing small joints. We have developed a multimodal photoacoustic/ultrasound (PA/US) imaging system, equipped with a handheld probe, which can provide dual-wavelength PA/US imaging to identify the micro-vessels of the inflamed articular regions and measure the oxygenation level of human inflamed synovium.

Objectives:

To validate the potential value for RA of the imaging system.

Methods:

A total of 32 RA patients received PA/US examination on seven small joints (MCP2, MCP3, PIP2, PIP3, MTP2, MTP5, and wrist of the clinically dominant side). The 0-3 score was used to semi-quantify the PA and PD signals of the inflammatory articular lesions, and the sums of PA and PD scores (PA-sum and PD-sum) were utilized. The relative oxygen saturation (SO2) values of the inflamed regions were measured by calculating the ratio of PA signals at the wavelength of 750nm and 830nm. All the patients were classified to 3 PA+SO2 patterns (Pattern 1: no or minimal PA signals; Pattern 2: evident PA signals and hyperoxia; Pattern 3: evident PA signals and hypoxia). The correlations between imaging scores and laboratory data, as well as clinical scoring systems were assessed.

Results:

A total of 32 patients of RA were recruited aged from 25-71 years-old were examined. PD-sum had moderate correlation with the clinical scores (r=0.529, 0.546, 0.490, 0.493 for DAS28ESR, DAS28CRP, SDAI, CDAI), moderate correlations with TJC (r=0.575) and SJC (r=0.491), fair correlation with VAS (r=0.239), poor correlation with PGA (r=0.153), and moderate correlation with EGA (r=0.457). The PA-sum had substantial correlations with the clinical scores (r= 0.699, 0.746, 0.723, 0.736 for DAS28ESR, DAS28CRP, SDAI, CDAI), substantial correlations with TJC (r=0.787) and SJC (r=0.694), moderate correlations with VAS (r=0.544) and PGA (r=0.529), and substantial correlation with EGA (r=0.708).

Ten patients were classified as Pattern 1, 12 as Pattern 2, 9 as Pattern 3. The PA+ SO2 patterns presented substantial correlations with the clinical scores (DAS28ESR r=0.690, DAS28CRP r=0.782, SDAI r=0.805, CDAI r=0.799, SJC r=647, TJC r=0.676, respectively), substantial correlation with VAS (r=0.714), and moderate correlation with PGA (r=0.476) and EGA (r=0.502). Significant differences between those who were classified as hypoxia and hyperoxia with evident PA signals, were detected in VAS (p=0.020) and PGA (p=0.026).

Conclusion:

The PA-sum scores and the PA+SO2 patterns can be utilized as objective imaging parameters reflecting the disease activity of RA. PAI may serve as a supplement to conventional US examinations for RA patients.

References:

[1]Backhaus, M., et al., Evaluation of a novel 7-joint ultrasound score in daily rheumatologic practice: a pilot project. Arthritis Rheum, 2009. 61(9): p. 1194-201.

[2]Colebatch, A.N., et al., EULAR recommendations for the use of imaging of the joints in the clinical management of rheumatoid arthritis. Ann Rheum Dis, 2013. 72(6): p. 804-14.

Figure 1.

the photo of the multimodal PA/US imaging system

Figure 2.

an example of the PA/US imaging

Disclosure of Interests:

Chenyang Zhao: None declared, Qian Wang: None declared, Xixi Tao: None declared, Chen Yu: None declared, Sirui Liu: None declared, Mengtao Li: None declared, Xinping Tian: None declared, Zhenhong Qi: None declared, Jianchu Li: None declared, Fang Yang: None declared, Lei Zhu: None declared, Xiaofeng Zeng Consultant of: MSD Pharmaceuticals, Meng Yang: None declared, Yuxin Jiang: None declared

Comparison of microRNAs in adipose and muscle tissue from seven indigenous Chinese breeds and Yorkshire pigs

Elucidation of the pig microRNAome is essential for interpreting functional elements of the genome and understanding the genetic architecture of complex traits. Here, we extracted small RNAs from skeletal muscle and adipose tissue, and we compared their expression levels between one Western breed (Yorkshire) and seven indigenous Chinese breeds. We detected the expression of 172 known porcine microRNAs (miRNAs) and 181 novel miRNAs. Differential expression analysis found 92 and 12 differentially expressed miRNAs in adipose and muscle tissue respectively. We found that different Chinese breeds shared common directional miRNA expression changes compared to Yorkshire pigs. Some miRNAs differentially expressed across multiple Chinese breeds, including ssc-miR-129-5p, ssc-miR-30 and ssc-miR-150, are involved in adipose tissue function. Functional enrichment analysis revealed that the target genes of the differentially expressed miRNAs are associated mainly with signaling pathways rather than metabolic and biosynthetic processes. The miRNA-target gene and miRNA-phenotypic traits networks identified many hub miRNAs that regulate a large number of target genes or phenotypic traits. Specifically, we found that intramuscular fat content is regulated by the greatest number of miRNAs in muscle tissue. This study provides valuable new candidate miRNAs that will aid in the improvement of meat quality and production.

[A comparative study of the calcaneal closing-wedge calcaneal osteotomy versus posterior-superior prominence removal in both sides with Haglund syndrome]

Objective: To compare the clinical outcome of removal of calcaneal posterior-superior prominence and that of calcaneal closing-wedge osteotomy for Haglund syndrome. Methods: From February 2009 to July 2014, 36 patients with Haglund syndrome were included.They were divided into two groups, and each group included 18 patients and underwent removal of calcaneal posterior-superior prominence and calcaneal closing-wedge osteotomy respectively.They were evaluated preoperatively and after 6 , 12 months and 24 months postoperatively by American Orthopedic Foot & Ankle Society (AOFAS) score, VAS score, VISA-A questionnaire and Maryland Foot Score.Fowler-Philip angle and calcaneal posterior slope of the two groups were compared preoperatively and after 6 months.All data were analysis utilizing SPSS 18.0. Results: At six months of follow-up, the weight-bearing lateral X-rays reveals that removal of calcaneal posterior-superior prominence did not change Fowler-Philip angle and calcaneal posterior slope and calcaneal closing-wedge osteotomy decreased Fowler-Philip angle and calcaneal posterior slope significantly[from preoperation (56.5±5.4)°, (120.0±1.3)°to postoperation (48.4±4.6)°, (109.0±5.3)°]. At six months of follow-up, the AOFAS score, VAS score, VISA-A questionnaire and Maryland Foot Score were worse in the wedge calcaneal osteotomy group.At twelve months of follow-up, no significant difference (P>0.05)was found between the two groups in terms of VAS score, and Maryland Foot Score, while the AOFAS score, and VISA-A questionnaire in the wedge calcaneal osteotomy group were better than those of posterior-superior prominence removal group.At twenty-four months of follow-up, the AOFAS score, VAS score, VISA-A questionnaire and Maryland Foot Score were better in the wedge calcaneal osteotomy group (P<0.05). Conclusions: Both the two surgical methods are effective for Haglund syndrome.Calcaneal closing-wedge osteotomy decreased Fowler-Philip angle and calcaneal posterior slope of calcaneus and its clinical outcome appears better than that removal of calcaneal posterior-superior prominence.