Contribution of mono- and co-culture of Pseudomonas paralactis, Acinetobacter MN21 and Stenotrophomonas maltophilia to the spoilage of chill-stored lamb.

Exploring the contribution of common microorganisms to spoilage is of great significance in inhibiting spoilage in lamb. This work investigated the extent of protein degradation and profile changes of free amino acids (FAAs), free fatty acids (FFAs) and volatile organic compounds (VOCs) in lamb caused by single- and co-culture of the common aerobic spoilage bacteria, P. paralactis, Ac. MN21 and S. maltophilia. Meanwhile, some key VOCs produced by the three bacteria during lamb spoilage were also screened by orthogonal partial least square discriminant analysis and difference value in VOCs content between inoculated groups and sterile group. Lamb inoculated with P. paralactis had the higher total viable counts, pH, total volatile base nitrogen and TCA-soluble peptides than those with the other two bacteria. Some FAAs and FFAs could be uniquely degraded by P. paralactis but not Ac. MN21 and S. maltophilia, such as Arg, Glu, C15:0, C18:0 and C18:1n9t. Co-culture of the three bacteria significantly promoted the overall spoilage, including bacterial growth, proteolysis and lipolysis. Key VOCs produced by P. paralactis were 2, 3-octanedione, those by Ac. MN21 were 1-octanol, octanal, hexanoic acid, 1-pentanol and hexanoic acid methyl ester, and that by S. maltophilia were hexanoic acid. The production of extensive key-VOCs was significantly and negatively correlated with C20:0, C23:0 and C18:ln9t degradation. This study can provide a basis for inhibiting common spoilage bacteria and promoting high-quality processing of fresh lamb.

Effects of different cold chain logistics modes on the quality and bacterial community succession of fresh pork.

The connection and temperature control of cold chain links are key to ensuring meat quality. Considering the practical production of cold chain logistics in China, this study investigated the impact of various cold chain logistics modes (including warehousing, transportation, and sales conditions) at different temperature settings (7 °C, 4 °C, and - 1 °C), modeled in the laboratory, on the quality and bacterial community succession of pork. The pork quality was evaluated by pH, water holding capacity, total volatile basic nitrogen (TVB-N), total viable count (TVC) and myowater status. Among the different cold chain logistics modes, the LL1 (samples being warehoused and transported at 4 °C for 96 h and sold at -1 °C) and the SL1 (samples being warehoused and transported at 4 °C for 30 h and sold at -1 °C) modes were suitable for inter-provincial and intra-provincial transportation due to their long shelf life (> 14 days), respectively. The bacterial community succession of pork in different cold chain logistics modes was accessed by high-throughput sequencing. The results indicated that the cold chain logistics modes had affected the bacterial community, with Latilactobacillus being the dominant bacteria in the LL1 mode and SL1 mode during spoilage. The study revealed that the entire or partial process supercooling treatment (-1 °C) during the cold chain logistics process could effectively preserve the meat quality, supporting the high-quality development of the fresh meat cold chain logistics.

Zein and tannic acid hybrid particles improving physical stability, controlled release properties, and antimicrobial activity of cinnamon essential oil loaded Pickering emulsions.

Pickering emulsion loading essential oil has demonstrated a promising strategy as delivery system in food preservation, but localization in stability and antimicrobial activity limits application. In this study, Pickering emulsions co-loaded with tannic acid and cinnamon essential oil (ZTC) have been developed based on zein and tannic acid complexes (ZT) mediated interfacial engineering. Fourier transform infrared, fluorescence spectroscopy, and molecular docking results indicated tannic acid altered the structural of zein. Interfacial tension results indicated that tannic acid accelerated the adsorbed speed of zein particles by decreased interfacial tension (11.99-9.96 mN/m). ZT5 formed a viscoelastic and dense layer in oil-water interface than that for other ZTs, which improved stability and control release performance of ZTC. Furthermore, the ZTC showed an effective antimicrobial activity against spoilage organisms Pseudomonad paralactis MN10 and Lactobacillus sakei VMR17. These findings provide new insight for developing co-loaded multiple antimicrobial agents within Pickering emulsion as a delivery system.

Identification of safe channels for screws in the anterior pelvic ring fixation system.

BACKGROUND: Minimally invasive surgery for pelvic fracture using anterior ring internal fixator system is increasing gradually, and the way to insert the fixation screws in the fixation system is the key technical points of the method. However, there have been few studies on insertion of fixation screws for the anterior pelvic ring internal fixator system. OBJECTIVE: To identify safe channels for fixation screws in the anterior pelvic fixator system and provide the anatomical basis for insertion of fixation screws in clinical operation. METHODS: Screw insertion was simulated into a total of 40 pelvic finite element models as well as 16 fresh pelvic specimens, and the channel parameters were measured. RESULTS: Finite elements (male, female) include: screws in ilium: length 114.4 ± 4.1 and 107.6 ± 8.3 mm, respectively; diameter 11.7 ± 0.5 and 10.0 ± 0.6 mm, distance between screw and anterior inferior iliac spine: 5.5 ± 1.0 and 5.6 ± 1.0 mm, angle of coronal plane 55.8° ± 2.4° and 50.6° ± 3.1°, angle of sagittal plane 26.6° ± 1.0° and 24.5° ± 1.9° and angle of horizontal plane 64.9 ± 3.7 and 58.1 ± 3.1; screws in pubis: length 47.0 ± 2.0 and 39.8 ± 3.9 mm, diameter 7.1 ± 0.4 and 6.1 ± 0.4 mm. Specimens (male, female) include: distance between screw and anterior inferior iliac spine: 5.5 ± 0.5 and 5.6 ± 0.7 mm, angle of coronal plane 55.9° ± 1.3° and 50.7° ± 1.5°, angle of sagittal plane 26.7° ± 0.5° and 24.1° ± 0.9° and angle of horizontal plane 64.8° ± 0.6° and 58.8° ± 0.8°. In the comparison between female and male in each group, differences in distances between screws and anterior inferior iliac spine and median line of symphysis pubis (P > 0.05) were not statistically significant; differences in the remaining parameters were statistically significant (P < 0.05). CONCLUSIONS: If surgeons paid attention to sex differences, select screws of appropriate diameter and length and hold the insertion position and direction, screws in the anterior pelvic ring fixation system could be safely inserted.

Dynamic changes of bacteria and screening of potential spoilage markers of lamb in aerobic and vacuum packaging.

Microorganisms proliferate, consume nutrients, and produce many undesired metabolites, which are the main reason for the spoilage of fresh meat. Screening spoilage markers is of great significance for characterizing the freshness of fresh meat. At present, there are few studies on the volatile spoilage markers (VSMs) of lamb and their relationship with bacteria. In this study, the spoilage evolution of lamb was evaluated by multiple indicators. The changes of bacteria and volatile organic compounds (VOCs) in aerobic-packaged (AP) and vacuum-packaged (VP) lamb were measured by 16S next-generation sequencing (NGS) and headspace solid-phase microextraction (HS-SPME)-gas chromatography-mass spectrometry (GC-MS) respectively. The potential VSMs were also screened. Results showed that the shelf life of AP lamb at 4 °C was less than 10 d and VP lamb was less than 28 d. Pseudomonas was the dominant bacteria in AP lamb, while Latilactobacillus and Lactococcus were the dominant bacteria in VP lamb. Several VOCs could be recommended as potential spoilage markers, including 1-octen-3-ol, 1-hexanol, nonanal, methoxy-phenyloxime, 2,3-octanedione, acetoin and 1-pentanol for AP lamb; acetoin, 1-hexanol, 2,3-octanedione, hexanoic acid, 1-octen-3-ol, nonanal, hexanal and 2,3-octanediol for VP lamb. This study can provide information for characterizing and predicting the freshness of fresh lamb.

Enrichment of Wee1/CDC2 and NF-κB Signaling Pathway Constituents Mutually Contributes to CDDP Resistance in Human Osteosarcoma.

PURPOSE: Osteosarcoma (OS) universally exhibits heterogeneity and cisplatin (CDDP) resistance. Although the Wee1/CDC2 and nuclear factor кB (NF-κB) pathways were reported to show abnormal activation in some tumor cells with CDDP resistance, whether there is any concrete connection is currently unclear. We explored it in human OS cells. MATERIALS AND METHODS: Multiple OS cell lines were exposed to a Wee1 inhibitor (AZD1775) and CDDP to assess the half-maximal inhibitory concentration values. Western blot, coimmunoprecipitation, confocal immunofluorescence, cell cycle, and Cell Counting Kit-8assays were performed to explore the connection between the Wee1/CDC2 and NF-κB pathways and their subsequent physiological contribution to CDDP resistance. Finally, CDDP-resistant PDX-OS xenograft models were established to confirm that AZD1775 restores the antitumor effects of CDDP. RESULTS: A sensitivity hierarchy of OS cells to CDDP and AZD1775 exists. In the highly CDDP-tolerant cell lines, Wee1 and RelA were physically crosslinked, which resulted in increased abundance of phosphorylated CDC2 (Y15) and RelA (S536) and consequent modulation of cell cycle progression, survival, and proliferation. Wee1 inhibition restored the effects of CDDP on these processes in CDDP-resistant OS cells. In addition, animal experiments with CDDP-resistant PDX-OS cells showed that AZD1775 combined with CDDP not only restored CDDP efficacy but also amplified AZD1775 in inhibiting tumor growth and prolonged the median survival of the mice. CONCLUSION: Simultaneous enrichment of molecules in the Wee1/CDC2 and NF-κB pathways and their consequent coactivation is a new molecular mechanism of CDDP resistance in OS cells. OS with this molecular signature may respond well to Wee1 inhibition as an alternative treatment strategy.

Effects of Different Storage Temperatures on the Physicochemical Properties and Bacterial Community Structure of Fresh Lamb Meat.

This study was aimed to compare the physicochemical properties and bacterial community structure of tray-packaged fresh lamb meat under different storage temperatures, such as 4°C (chilling), -1.5°C (supercooling), -4°C (superchilling) and -9°C (sub-freezing). The total viable counts (TVC), total volatile base nitrogen (TVB-N), bacterial diversity and metabolic pathways were investigated. The results indicated that the shelf life of superchilling and sub-freezing storage was over 70 d, which was significantly longer than that of chilling and supercooling storage. TVC and TVB-N values showed an increasing trend and were correlated well (R2>0.92). And the TVB-N values of lamb meat were exceeded the tolerable limit (15 mg/100 g) only found under chilling and supercooling storage during storage period. At the genus level, Pseudomonas was the core spoilage bacteria then followed Brochothrix for chilling and supercooling storage. Pseudomonas, Ralstonia, Psychrobacter and Acinetobacter were the dominant spoilage bacteria for superchilling and sub-freezing storage. Furthermore, the bacterial community diversity of lamb meat stored at chilling and supercooling storage decreased with the storage time prolonged, which was opposite to the outcome of meat stored under superchilling and sub-freezing storage. For chilling and supercooling storage, the abundance of main metabolisms (carbohydrate metabolism and amino acid metabolism, etc.) of bacteria increased with the storage time prolonged, which was opposite to superchilling storage. This may be related to the bacteria community diversity and the formation of dominant spoilage bacteria. In conclusion, this work provides data for the preservation of fresh lamb meat which will benefit the meat industry.

Three-dimensional printing of patient-specific plates for the treatment of acetabular fractures involving quadrilateral plate disruption.

BACKGROUND: Complicated acetabular fractures comprise the most challenging field for orthopedists. The purpose of this study was to develop three-dimensional printed patient-specific (3DPPS) Ti-6Al-4 V plates to treat complicated acetabular fractures involving quadrilateral plate (QLP) disruption and to evaluate their efficacy. METHODS: Fifty patients with acetabular fractures involving QLP disruption were selected between January 2016 and June 2017. Patients were divided into a control group (Group A, 35 patients) and an experimental group (Group B, 15 patients), and were treated by the conventional method of shaping reconstruction plates or with 3DPPS Ti-6AL-4 V plates, respectively. The efficacy of Ti-6AL-4 V plates was evaluated by blood loss, operative time, reduction quality, postoperative residual displacement, and complications. RESULTS: The operative time and blood loss in Group B were reduced compared to Group A, and the difference was statistically significant (P < 0.05). There was no significant difference in reduction quality between the two groups (P > 0.05). Reduction quality in Group B was anatomic in 10 (66.7%), satisfactory in four (26.7%), and poor in one (6.7%). In Group A, they were anatomic in 18 (51.4%), satisfactory in 13 (37.1%), and poor in four (11.4%). Residual displacement in Group B was less than that in Group A, and the difference was statistically significant (P < 0.05). In Group B, one case exhibited loosening of the pubic screw postoperatively. In Group A, there was one case of wound infection, one of deep vein thrombosis (DVT) in the ipsilateral lower limb, one case of traumatic arthritis and two obturator nerve injuries. CONCLUSIONS: The 3DPPS Ti-6AL-4 V plate is a feasible, accurate and effective implant for acetabular fracture treatment.

Comparative biomechanical testing of customized three-dimensional printing acetabular-wing plates for complex acetabular fractures.

BACKGROUND: Three-dimensional (3D) printing of an acetabular wing-plate is a new minimally invasive surgical technique for complex acetabular fractures. OBJECTIVES: To investigate the biomechanical stability of 3D printing acetabular wing-plates. The results were compared with 2 conventional fixation systems. MATERIAL AND METHODS: Eighteen fresh frozen cadaveric pelvises with both column fractures were randomly divided to 3 groups: A - iliosciatic plates fixation system; B - 3D printing plates; C - 2 parallel reconstruction plates fixation system. These constructions were loaded onto a biomechanical testing machine. Longitudinal displacement and stiffness values of the constructs were measured to estimate their stability. RESULTS: When the load force reached 700 N, Group A was superior to Group B in the longitudinal displacement of point 1 (p > 0.05). The longitudinal displacement of point 2 showed no significant differences among Groups A, B and C, and the displacement of the fracture line over point 3 showed no significant differences between Groups A and B (p > 0.05). The axial stiffness of Groups A, B and C were 122.4800 ±8.8480 N/mm, 168.4830 ±14.8091 N/mm and 83.1300 ±3.8091 N/mm, respectively. Group B was significantly stiffer than A and C (p < 0.05). Loads at failure of internal fixation were 1378.83 ±34.383 N, 1516.83 ±30.896 N and 1351.00 ±26.046 N for Groups A, B and C, respectively. Group B was significantly superior to Groups A and C (p > 0.05). CONCLUSIONS: Customized 3D printing acetabular-wing plates provide stability for acetabular fractures compared to intraspecific buttressing fixation.

Biomechanics of Anterior Ring Internal Fixation Combined with Sacroiliac Screw Fixation for Tile C3 Pelvic Fractures.

BACKGROUND Despite the development of minimally invasive techniques for pelvic fractures, performing minimally invasive surgery for Tile C3 pelvic fractures remains challenging. Thus, we propose use of anterior ring internal fixation combined with sacroiliac screw fixation for Tile C3 pelvic fractures. MATERIAL AND METHODS A normal pelvic finite element model (model 1) was established. Two-screw, three-screw, and four-screw anterior ring internal fixators and plate combined with sacroiliac screw Tile C3 pelvic fracture models (models 2, 3, 4, and 5, respectively) were also established. A vertical load of 600 N was applied on S1. The distribution of displacement and stress in the standing and sitting positions was compared. RESULTS Models 2, 3, 4, and 5 can provide effective fixation. Compared with model 1, in the erect position, the maximum displacement of models 2, 3, 4, and 5 increased by 66.51%, 65.36%, 35.16%, and 35.47% and the maximum stress increased by 201.78%, 130.65%, 100.82%, and 99.03%, respectively. Compared with model 1, in sitting position, the maximum displacement of models 2, 3, 4, and 5 increased by 9.1%, 11.04%, 5.57%, and 8.59% and the maximum stress increased by 157.73%, 118.02%, 98.32%, and 93.16%, respectively. CONCLUSIONS Anterior ring internal fixators combined with sacroiliac screws can effectively fix Tile C3 pelvic fractures.

The application of lateral-rectus approach on toddlers' unstable pelvic fractures.

BACKGROUND: Pelvic fractures are rare in toddlers but are often associated with other injuries that make treatment difficult. Conservative treatment has been used with moderate success, but it is unclear if surgical correction could confer additional benefits and improve patient outcomes. The purpose of this study was to report authors' experience using the lateral-rectus approach (LRA) for surgical correction of unstable pelvic fractures in two toddlers. METHODS: We retrospectively analyzed the cases of two toddlers with unstable pelvic fractures who underwent surgery through the LRA between April 2016 and October 2018. Patients' characteristics, fracture type, mechanism of injury, Injury Severity Score (ISS), operative time, intra-operative blood loss, and post-operative complications were assessed. Pelvic asymmetry, degree of deformity, Cole scoring criteria and modified Barthel Index (MBI) were used to evaluate radiographic and functional outcomes. RESULTS: Successful surgical treatment was performed using the LRA, external fixation, and sacroiliac screw fixation. Surgery duration was 180 min on average, with an average intra-operative bleeding of 250 ml. There were no iatrogenic nerve injuries or infections. Pelvic asymmetry a week after surgery was 0.5 cm on average and dropped to 0.3 cm on average at the end of the follow-up period. The deformity index of the pelvis dropped from an average of 0.035 a week after surgery to 0.02 at the end of the follow-up period. The mean MBI was 100 in the last follow-up, and Cole scoring criteria categorized both patients as being in excellent condition. All patients achieved radiological bone union without discrepancy in length of the lower limbs. Neither patient had loss of reduction nor evidence of low back pain during the mean follow-up period of 22 months. CONCLUSIONS: Pelvic fracture in toddlers is rare, and surgical treatment requires careful consideration. The lateral-rectus approach was proven as a viable alternative for managing unstable pelvic fractures in toddlers, with minimal blood loss and risk of nerve injury. Furthermore, anterior external fixation and posterior sacroiliac screw fixation would be adequate for this population, with excellent final outcome.

Evidence of the genetic diversity and clonal population structure of Oenococcus oeni strains isolated from different wine-making regions of China.

Studies of the genetic diversity and population structure of Oenococcus oeni (O. oeni) strains from China are lacking compared to other countries and regions. In this study, amplified fragment length polymorphism (AFLP) and multilocus sequence typing (MLST) methods were used to investigate the genetic diversity and regional evolutionary patterns of 38 O. oeni strains isolated from different wine-making regions in China. The results indicated that AFLP was markedly more efficient than MLST for typing O. oeni strains. AFLP distinguished 37 DNA patterns compared to 7 sequence types identified using MLST, corresponding to discriminatory indices of 0.999 and 0.602, respectively. The AFLP results revealed a high level of genetic diversity among the O. oeni strains from different regions of China, since two subpopulations and an intraspecific homology higher than 60% were observed. Phylogenetic analysis of the O. oeni strains using the MLST method also identified two major phylogroups, which were differentiated into two distinct clonal complexes by minimum spanning tree analysis. Neither intragenic nor intergenic recombination verified the existence of the clonal population structure of the O. oeni strains.