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INTRODUCTION: Brain organoids are believed to be able to regenerate impaired neural circuits and reinstate brain functionality. The neuronal activity of organoids is considered a crucial factor for restoring host function after implantation. However, the optimal stage of brain organoid post-transplantation has not yet been established. External electrical signal plays a crucial role in the physiology and development of a majority of human tissues. However, whether electrical input modulates the development of brain organoids, making them ideal transplant donors, is elusive. METHODS: Bioelectricity was input into cortical organoids by electrical stimulation (ES) with a multi-electrode array (MEA) to obtain a better-transplanted candidate with better viability and maturity, realizing structural-functional integration with the host brain. RESULTS: We found that electrical stimulation facilitated the differentiation and maturation of organoids, displaying well-defined cortical plates and robust functional electrophysiology, which was probably mediated via the pathway of calcium-calmodulin (CaM) dependent protein kinase II (CAMK II)-protein kinase A (PKA)-cyclic-AMP response binding protein (pCREB). The ES-pretreated D40 organoids displayed superior cell viability and higher cell maturity, and were selected to transplant into the damaged primary sensory cortex (S1) of host. The enhanced maturation was exhibited within grafts after transplantation, including synapses and complex functional activities. Moreover, structural-functional integration between grafts and host was observed, conducive to strengthening functional connectivity and restoring the function of the host injury. CONCLUSION: Our findings supported that electrical stimulation could promote the development of cortical organoids. ES-pretreated organoids were better-transplanted donors for strengthening connectivity between grafts and host. Our work presented a new physical approach to regulating organoids, potentially providing a novel translational strategy for functional recovery after brain injury. In the future, the development of 3D flexible electrodes is anticipated to overcome the drawbacks of 2D planar MEA, promisingly achieving multimodal stimulation and long-term recordings of brain organoids.

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BACKGROUND: Cholecystectomy is a successful treatment option for gallstones, although the incidence of colorectal cancer (CRC) has notably increased in post-cholecystectomy (PC) patients. However, it remains uncertain whether the altered mucosal microbiota in the ascending colon is related. AIM: To investigate the potential correlation between gut microbiota and the surgical procedure of cholecystectomy. METHODS: In total, 30 PC patients and 28 healthy controls underwent colonoscopies to collect mucosal biopsy samples. PC patients were divided based on their clinical features. Then, 16S-rRNA gene sequencing was used to analyze the amplicon, alpha diversity, beta diversity, and composition of the bacterial communities. Additionally, the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) database, sourced from the Kyoto Encyclopedia of Genes and Genomes, was used to predict the functional capabilities of the bacteria. RESULTS: PC patients were comparable with healthy controls. However, PC patients older than 60 years had a distinct composition compared to those under 60 years old. Bacteroidetes richness was considerably higher at the phylum level in PC patients. Bacteroides, Parabacteroides, and Bilophila were more abundant in the PC group than in the control group. Furthermore, PC patients exhibited greater enrichment in metabolic pathways, specifically those related to lipopolysaccharide biosynthesis and vancomycin group antibiotic production, than controls. CONCLUSION: This study indicated that the mucosal microbiota in PC patients was altered, perhaps offering new perspectives on the treatment possibilities for CRC and diarrhea following cholecystectomy.

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BACKGROUND: This study aimed to explore the genetic basis of a fetus with ultrasound indicating a thickening of the nuchal translucency (NT) and a choroid plexus cyst. METHODS: Fetal amniotic fluid and peripheral blood were collected for a G-banding karyotype analysis and single nucleotide polymorphism array (SNP-array) detection. RESULTS: The chromosome karyotypes of the fetus and its parents were normal. SNP-array showed the fetus had carried 277 kb microdeletion at 14q11.2, which was a new mutation. After the induced abortion, the fetus was diagnosed with macrocephaly. CONCLUSIONS: A prenatal diagnosis of a fetus with 14q11.2 microdeletion-induced intrauterine growth retardation was confirmed, which has provided guidance for the subsequent pregnancy.

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In this study, we delved into the prototypical components and metabolites of Platycodonis Radix extracts(PRE) from Tongcheng city in plasma, urine and feces of rats, and revealed its metabolic pathways and metabolic rules in vivo. The prototypical components and metabolites of PRE in rats were characterized and identified by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and mass defect filter(MDF). The biological samples were analyzed by ACQUITY UPLC BEH C_(18)(2.1 mm×100 mm, 1.7 µm), with 0.1% formic acid water(A)-0.1% formic acid acetonitrile(B) as mobile phase, and the biological samples were analyzed in negative ion mode by electrospray ionization mass spectrometry(ESI-MS). Twelve prototypical saponins and twenty-seven metabolites were detected in plasma, urine and feces of rats treated with PRE by oral administration. Eleven prototypical components and nine metabolites were detected in plasma, eleven prototypical components and eight metabo-lites were detected in urine, and ten prototypical components and twenty metabolites were detected in feces. Further studies showed that the metabolic pathways of PRE in rats mainly include oxidation, reduction, acetylation, stepwise hydrolytic deglycosylation, glucuronidation and so on. This study provides a scientific basis for clarifying the pharmacological basis and mechanism of PRE from Tongcheng city.

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Mn-based sodium superionic conductors have driven attention to the low-cost advanced cathode materials for sodium-ion batteries (SIBs). However, low-rate capability and unsatisfactory cyclic performance due to the Jahn teller effect of Mn3+ redox couple which occurs from the change in Mn-O bond length at the octahedral site of crystal structure during charge-discharge, eventually limiting their application. Herein, a disordered and sodium deficient NASICON Na4-xMn(FeVCrTi)0.25(PO4)3 (termed as Na4-xMn(HE)) is synthesized to mitigate this Jahn teller effect to achieve high rate and ultrastable cathode material. Interestingly, the as-prepared Na3.5Mn(HE) shows five reversible electron reactions (i.e., Ti3+/Ti4+, Fe2+/Fe3+, V3+/V4+, Mn2+/Mn3+, and Mn3+/Mn4+) and demonstrates 141 mA h g-1 at 0.2 C with 80% capacity retention at 1 C after 500 cycles which is far superior to its counterparts binary Mn-based materials. The excellent cyclic performance is due to the remediation of the Jahn teller effect in sodium-deficient entropy-stabilized material. The structural reversibility, enhanced kinetics, and electronic properties are further studied in detail by in situ X-ray diffraction (XRD), ex situ X-ray photoelectron spectroscopy (XPS), and first principal calculations. Na3.5Mn(HE)//HC full cell delivered 89.7 mAh g-1 capacity at 0.2 C. This work sheds light on designing Mn-based cathodes with superior electrochemical performance for wide energy storage applications.

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Fusarium rot on melon fruit has become an important postharvest disease for producers worldwide, typically involving multiple Fusarium pathogens (Khuna et al. 2022; Medeiros Araújo et al. 2021). In 2022, Fusarium fruit rot of muskmelon (Cucumis melo var. conomon) occurred sporadically in a field at Huainan Academy of Agricultural Sciences (32.658193º N, 117.064922º E) with an incidence of about 10%. Among these diseased muskmelons, a fruit exhibiting a white to yellowish colony athe intersection of the diseased and healthy tissues was collected and labeled TGGF22-17. The streak plate method was employed to isolate fungal spores on Bengal Red PDA (potato dextrose agar), which were then incubated at 25℃ in darkness. Following isolation and purification, a single-spore strain, TGGF22-17, was obtained and analyzed using morphological characters on PDA, synthetic nutrient agar (SNA) and carnation leaf agar (CLA) (Leslie and Summerell 2006), along with molecular identification. Colours were rated according to the color charts of Kornerup and Wanscher (1978). Based on the colony morphology on PDA, the isolate displayed a rosy buff or buff color with a white to buff margin. The colony margin was undulate, with the reverse transitioning from amber-yellow to honey-yellow. Aerial macroconidia on SNA were thin-walled, hyaline, mostly 3-5 septate, falcate, and measured 18.5-46.4 (x̄=34.2) × 2.9-4.8 (x̄ =3.9) µm in size (n =50). Sporodochial macroconidia on CLA were mostly five-septate with long apical and basal cells, exhibiting dorsiventral curvature. They were hyaline, with the apical cell hooked to tapering and the basal cell foot-shaped, measuring 46.5-89.6 (x̄ =72.3) × 3.5-5.0 (x̄ =4.3) µm in size (n = 100). Portions of three loci (TEF-1α, RPB1 and RPB2) were amplified and sequenced as described by Wang et al. (2019). Sequences were deposited in GenBank with accession number PP196583 to PP196585. The three gene sequences (TEF-1α, RPB1 and RPB2) of strain TGGF2022-17 shared 99.5% (629/632bp), 97.9% (1508/1540 bp) and 99.9% (1608/1609 bp) identity to the ex-type strain F. ipomoeae LC12165 respectively by pairwise DNA alignments on the FUSARIOID-ID database (https://www.fusarium.org). Phylogenetic analysis of the partial TEF-1α and RPB2 sequences with PhyloSuite (Zhang et al. 2020) showed the isolated fungus clustered with F. ipomoeae. Based on the morphological and phylogenetic analyses, TGGF22-17 was identified as F. ipomoeae. Pathogenicity tests were performed on healthy melons, which were surface-sterilized with 75% alcohol and wounded using a sterilized inoculation needle. A 4-mm diameter plug from a 7-day-old SNA culture of TGGF22-17 was aseptically inserted in the middle of the wound, sealed with plastic bag after absorbent cotton was included to maintain moisture. Five melons were each inoculated at three points. Noncolonized PDA agar plugs served as the negative control. The inoculated and uninoculated plugs were removed approximately 48 hours after inoculation. The melon inoculated with TGGF22-17 exhibited water-soaked black lesions 48h post-inoculation, resulting in a 100% infection rate (15/15). After 7 days, mycelium was obseved on the inoculated melons. No disease symptoms were observed on the uninoculated melons. To fulfill Koch's postulates, fungi were isolated from the inoculated fruit and confirmed as F. ipomoeae by morphological observation. Fusarium ipomoeae has been reported to cause fruit rot on winter squash (Cucurbita maxima) in Japan (Kitabayashi et al. 2023). To our knowledge, this is the first report of fruit rot on muskmelon caused by F. ipomoeae in China and this report will be valuable for monitoring and management of fruit rot disease on muskmelons.

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Background: The objective of this study was to investigate the association between pre-operative body mass index (BMI) and surgical infection in perihilar cholangiocarcinoma (pCCA) patients treated with curative resection. Methods: Consecutive pCCA patients were enrolled from four tertiary hospitals between 2008 and 2022. According to pre-operative BMI, the patients were divided into three groups: low BMI (≤18.4 kg/m2), normal BMI (18.5-24.9 kg/m2), and high BMI (≥25.0 kg/m2). The incidence of surgical infection among the three groups was compared. Multivariable logistic regression models were used to determine the independent risk factors associated with surgical infection. Results: A total of 371 patients were enrolled, including 283 patients (76.3%) in the normal BMI group, 30 patients (8.1%) in the low BMI group, and 58 patients (15.6%) in the high BMI group. The incidence of surgical infection was significantly higher in the patients in the low BMI and high BMI groups than in the normal BMI group. The multivariable logistic regression model showed that low BMI and high BMI were independently associated with the occurrence of surgical infection. Conclusions: The pCCA patients with a normal BMI treated with curative resection could have a lower risk of surgical infection than pCCA patients with an abnormal BMI.

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A new series of usnic acid (UA) monoesterified derivatives 2-15 were designed and synthesised using UA (1) as starting material. The structural characterisation of all compounds was elucidated using 1H-NMR and 13C-NMR spectral data. In vitro studies demonstrated thatmost UA derivatives exhibited higher inhibitory activity against Candida albicans and Staphylococcus aureus. Among them, compound 7 displayed the highest inhibitory activity against C. albicans with a minimum inhibitory concentration (MIC) of 32 µg/mL. Compounds 5, 8, 9, 11and 13 demonstrated superior inhibition of S. aureus (MIC, 16 µg/mL) and biofilm formation in a concentration-dependent manner. With the exception of 11, compounds 5, 8, 9 and 13 were all more effective than UA in inhibiting S. aureus biofilms. This research highlights the potential of UA monoesterified derivatives for the development of dual antimicrobial and antibiofilm agents.

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The Air Pollution Prevention and Control Action Plan （APPCAP） was promulgated in China in 2013. To explore the effectiveness of APPCAP on PM2.5 in winter in Zhengzhou, PM2.5 samples were collected in Zhengzhou Monitoring Center during December 2013 and December 2018. The chemical composition of PM2.5 was analyzed, including EC, OC, water soluble ions, and metal elements. Pollution episodes under different stages were selected to investigate the changes in PM2.5 concentration and composition. The results showed that： ① The average concentration of PM2.5 in winter in Zhengzhou decreased from （215.38 ±107.28） µg·m-3 in 2013 to （77.45 ±49.81） µg·m-3 in 2018, with a decrease rate of 64%. ② The concentrations of EC, K+, SO42-, and Cl- decreased by 85%, 80%, 78%, and 72%, respectively, and the decrease rate in OC, NH4+, and NO3- was 50%, 41%, and 32%, respectively. ③ Compared with those in winter of 2013, the ratios of OC/EC in winter of 2018 increased by 2.6 times, and the proportion of secondary organic carbon in OC increased to 57%； meanwhile, values of sulfur oxidation rate and nitrogen oxidation rate increased by 1.5 and 1.0 times, respectively, indicating heavy secondary pollution in Zhengzhou. ④ The mass ratios of NO3-/SO42-increased from 0.8 ±0.2 in 2013 to 2.5 ±1.0 in 2018, indicating that the contribution of mobile sources increased and surpassed fixed sources as the main source in Zhengzhou. ⑤The comparison results of different stages of the heavy pollution process showed that ρ（PM2.5） decreased significantly in 2018 compared with that in 2013, with the peak concentration decreasing by 61%. The main chemical composition changed from OC, NO3-, SO42-, and NH4+ to OC, NO3-, and NH4+. The results indicated that the primary emission source control in Zhengzhou had achieved remarkable effects, but the contribution of secondary generation to PM2.5 showed an elevated trend； thus, the influence of secondary generation requires further attention in the future.

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MicroRNAs (miRNAs) are small noncoding RNAs of 18-25 bases. miRNAs are also important new biomarkers that can be used for disease diagnosis in the future. Studies have shown that miR-124 levels are significantly elevated during acute myocardial infarction (AMI) and play a key role in the cardiovascular system. A variety of methods have been established to detect myocardial infarction-related miRNAs. However, most require complex miRNA extraction and isolation, and these methods are virtually undetectable when RNA levels are low in the sample. It may lead to biased results. Thus, it is necessary to develop a technique that can detect miRNA without extracting it, which means that intracellular detection is of great significance. Here, we improved the traditional silicon spheres and obtained a biosensor that could effectively capture and detect specific noncoding nucleic acids through the layer-by-layer assembly method. The sensor is protected by hyaluronic acid so it can successfully escape the lysosome into the cell and achieve detection. With the help of a full-featured microplate reader, we determined that the detection limit of the biosensor could reach 1 fM, meeting the needs of intracellular detection. At the same time, we prepared an oxidative stress cardiomyocyte infarction model and successfully captured the overexpressed miR-124 in the infarcted cells to achieve in situ detection. This study could provide a new potential tool to develop miRNAs for sensitive diagnosis in AMI, and the proposed strategy implies its potential for biomedical research.

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Kinases, a class of enzymes controlling various substrates phosphorylation, are pivotal in both physiological and pathological processes. Although their conserved ATP binding pockets pose challenges for achieving selectivity, this feature offers opportunities for drug repositioning of kinase inhibitors (KIs). This study presents a cost-effective in silico prediction of KIs drug repositioning via analyzing cross-docking results. We established the KIs database (278 unique KIs, 1834 bioactivity data points) and kinases database (357 kinase structures categorized by the DFG motif) for carrying out cross-docking. Comparative analysis of the docking scores and reported experimental bioactivity revealed that the Atypical, TK, and TKL superfamilies are suitable for drug repositioning. Among these kinase superfamilies, Olverematinib, Lapatinib, and Abemaciclib displayed enzymatic activity in our focused AKT-PI3K-mTOR pathway with IC50 values of 3.3, 3.2 and 5.8 µM. Further cell assays showed IC50 values of 0.2, 1.2 and 0.6 µM in tumor cells. The consistent result between prediction and validation demonstrated that repositioning KIs via in silico method is feasible.

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Objective: To investigate the clinical and molecular characteristics of Salmonella spp. causing bloodstream infections (BSIs) in our hospital. Methods: We studied 22 clinical Salmonella isolates from BSIs and 16 from non-BSIs, performing antimicrobial susceptibility testing (AST) and whole genome sequencing (WGS). The analysis included serovars, antibiotic resistance genes (ARGs), virulence factors (VFs), sequence types (STs), plasmid replicons, and genetic relationships. We also assessed pathogenicity of the isolates causing BSIs through growth, biofilm formation, and anti-serum killing assays. Results: WGS analysis identified 13 Salmonella serovars, with four responsible for BSIs. S. Enteritidis was the most prevalent serovar, involved in 19 (50.0%) cases. BSIs were caused by 17S. Enteritidis, two S. Typhimurium, two S. Munster and one S. Diguel. Of the 38 isolates, 27 (71.1%) exhibited high resistance to ampicillin, and 24 (63.2%) to ampicillin/sulbactam. Thirty-six types of ARGs were identified, with blaTEM-1B (n = 25, 65.8%) being the most frequent. Ten plasmid replicons were found; the combination of IncFIB(S)-IncFII(S)-IncX1 was the most common in S. Enteritidis (94.7%). Fifteen STs were identified, among which ST11 was the most prevalent and clonally disseminated, primarily responsible for BSIs. A total of 333 different VFs were detected, 177 of which were common across all strains. No significant differences were observed between the BSI and non-BSI isolates in terms of resistance rates, ARGs, plasmid replicons, and VFs, except for seven VFs. No strong pathogenicity was observed in the BSI-causing isolates. Conclusion: BSIs were predominantly caused by clonally disseminated S. Enteritidis ST11, the majority of which carried multiple ARGs, VFs and plasmid replicons. This study provides the first data on clonally disseminated S. Enteritidis ST11 causing BSIs, highlighting the urgent need for enhanced infection control measures.

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The reconstruction of neural function and recovery of chronic damage following traumatic brain injury (TBI) remain significant clinical challenges. Exosomes derived from neural stem cells (NSCs) offer various benefits in TBI treatment. Numerous studies confirmed that appropriate preconditioning methods enhanced the targeted efficacy of exosome therapy. Interferon-gamma (IFN-γ) possesses immunomodulatory capabilities and is widely involved in neurological disorders. In this study, IFN-γ was employed for preconditioning NSCs to enhance the efficacy of exosome (IFN-Exo, IE) for TBI. miRNA sequencing revealed the potential of IFN-Exo in promoting neural differentiation and modulating inflammatory responses. Through low-temperature 3D printing, IFN-Exo was combined with collagen/chitosan (3D-CC-IE) to preserve the biological activity of the exosome. The delivery of exosomes via biomaterial scaffolds benefited the retention and therapeutic potential of exosomes, ensuring that they could exert long-term effects at the injury site. The 3D-CC-IE scaffold exhibited excellent biocompatibility and mechanical properties. Subsequently, 3D-CC-IE scaffold significantly improved impaired motor and cognitive functions after TBI in rat. Histological results showed that 3D-CC-IE scaffold markedly facilitated the reconstruction of damaged neural tissue and promoted endogenous neurogenesis. Further mechanistic validation suggested that IFN-Exo alleviated neuroinflammation by modulating the MAPK/mTOR signaling pathway. In summary, the results of this study indicated that 3D-CC-IE scaffold engaged in long-term pathophysiological processes, fostering neural function recovery after TBI, offering a promising regenerative therapy avenue.

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Thawing is the primary step in handling frozen aquatic products, which directly determines their end-product quality. This study firstly constructed a novel thawing method of ultrasound-assisted slightly basic electrolyzed water (UST), and its influences on the physicochemical and histological properties of shrimp, as well as the structural of myofibrillar proteins (MPs) in shrimp were evaluated. Results indicated that the UST treatment greatly reduced 48.9 % thawing time of frozen shrimp compared to traditional thawing approaches. Meanwhile, the UST effectively decreased the generation of malondialdehyde (MDA), total volatile basic nitrogen (TVB-N), and carbonyl compounds in the thawed shrimps. In addition, it significantly preserved the elasticity and integrity of muscle fiber. Notably, the UST reduced the damage of thawing to the spatial structures of MPs, thereby greatly keeping the stability of protein. All these favorable changes maintained the water holding capacity (WHC) and quality of shrimp. Therefore, the UST is a promising non-thermal thawing technology for aquatic products.

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OBJECTIVE: Pulmonary hypertension is a severe complication of bronchiectasis, characterized by elevated pulmonary vascular resistance (PVR) and subsequent right heart failure. The association between PVR and mortality in bronchiectasis-associated pulmonary hypertension has not been investigated previously. METHODS: In the present study, a retrospective analysis was conducted on 139 consecutive patients diagnosed with bronchiectasis-associated pulmonary hypertension based on right heart catheterization, enrolled between January 2010 and June 2023. Baseline clinical characteristics and hemodynamic assessment were analyzed. The survival time for each patient was calculated in months from the date of diagnosis until the date of death or, if the patient was still alive, until their last visit. RESULTS: Patients with bronchiectasis-associated pulmonary hypertension exhibited estimated survival rates of 89.5, 70, and 52.9 at 1-year, 3-year, and 5-year intervals respectively, with a median survival time of 67 months. Multivariable Cox regression analysis revealed that increased age [(adjusted hazard ratio per year 1.042, 95% confidence interval (CI) 1.008-1.076, P  = 0.015] and elevated PVR (adjusted HR per 1 Wood Units 1.115, 95% CI 1.015-1.224, P  = 0.023) were associated with an increased risk of all-cause mortality. In contrast, higher BMI was associated with a decreased risk of all-cause death (adjusted hazard ratio per 1 kg/m 2 0.915, 95% CI 0.856-0.979, P  = 0.009). Receiver-operating characteristic analyses identified a cutoff value for PVR at 4 Wood Units as predictive for all-cause death within 3 years [area under the curve (AUC) = 0.624; specificity= 87.5%; sensitivity= 35.8%; P  < 0.05]. Patients with a PVR greater than 4 Wood Units had a significantly higher risk of all-cause death compared with those with 4 Wood Units or less (adjusted hazard ratio 2.392; 95% CI 1.316-4.349; P  = 0.019). Notably, there were no significant differences in age, sex, BMI, WHO functional class, 6-min walk distance, and NT-proBNP levels at baseline between patients categorized as having 4 Wood Units or less or greater than 4 Wood Units for PVR. CONCLUSION: Based on these data, PVR could serve as a discriminative marker for distinguishing between nonsevere pulmonary hypertension (PVR ≤ 4 Wood Units) and severe pulmonary hypertension (PVR > 4 Wood Units). The utilization of a PVR cutoff value of 4.0 Wood Units provides enhanced prognostic capabilities for predicting mortality.

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The demand for crayfish surimi products has grown recently due to its high protein content. This study examined the effects of varying κ-carrageenan (CAR) and crayfish surimi (CSM) concentrations on the gelling properties of CAR-CSM composite gel and its intrinsic formation process. Our findings demonstrated that with the increasing concentration of carrageenan, the quality of CAR-CSM exhibited rising trend followed by subsequently fall. Based on the textural qualities, the highest quality CAR-CSM was achieved at 0.3% carrageenan addition. With the exception of chewiness, and the cooking loss of the gel system was 1.62%, whiteness was 82.35%, and the percentage of ß-sheets increased to 57.18%. Further increase in CAR (0.4-0.5%) addition resulted in internal build-up of LCAR-CSM, conversion of intermolecular forces into disulfide bonds and gel breakage. This study exudes timely recommendations for extending the CAR application for the continuous development of crayfish surimi and its derivatives and its overall economic worth.

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[This corrects the article on p. 508 in vol. 15, PMID: 37900904.].

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The clustered regularly interspaced short palindromic repeats and their associated proteins (CRISPR-Cas) system widely occurs in prokaryotic organisms to recognize and destruct genetic invaders. Systematic collation and characterization of endogenous CRISPR-Cas systems are conducive to our understanding and potential utilization of this natural genetic machinery. In this study, we screened 39 complete and 692 incomplete genomes of myxobacteria using a combined strategy to dispose of the abridged genome information and revealed at least 19 CRISPR-Cas subtypes, which were distributed with a taxonomic difference and often lost stochastically in intraspecies strains. The cas genes in each subtype were evolutionarily clustered but deeply separated, while most of the CRISPRs were divided into four types based on the motif characteristics of repeat sequences. The spacers recorded in myxobacterial CRISPRs were in high G+C content, matching lots of phages, tiny amounts of plasmids, and, surprisingly, massive organismic genomes. We experimentally demonstrated the immune and self-target immune activities of three endogenous systems in Myxococcus xanthus DK1622 against artificial genetic invaders and revealed the microhomology-mediated end-joining mechanism for the immunity-induced DNA repair but not homology-directed repair. The panoramic view and immune activities imply potential omnipotent immune functions and applications of the endogenous CRISPR-Cas machinery. IMPORTANCE: Serving as an adaptive immune system, clustered regularly interspaced short palindromic repeats and their associated proteins (CRISPR-Cas) empower prokaryotes to fend off the intrusion of external genetic materials. Myxobacteria are a collective of swarming Gram-stain-negative predatory bacteria distinguished by intricate multicellular social behavior. An in-depth analysis of their intrinsic CRISPR-Cas systems is beneficial for our understanding of the survival strategies employed by host cells within their environmental niches. Moreover, the experimental findings presented in this study not only suggest the robust immune functions of CRISPR-Cas in myxobacteria but also their potential applications.

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This work set out to investigate how the physicochemical markers, volatiles, and metabolomic characteristics of mixed fermented the fermentation of Lycium barbarum and Polygonatum cyrtonema compound wine (LPCW) from S. cerevisine RW and D. hansenii AS2.45 changed over the course of fermentation. HS-SPME-GC-MS combined with non-targeted metabolomics was used to follow up and monitor the fermentation process of LPCW. In total, 43 volatile chemical substances, mostly alcohols, esters, acids, carbonyl compounds, etc., were discovered in LPCW. After 30 days of fermentation, phenylethyl alcohol had increased to 3045.83 g/mL, giving off a rose-like fresh scent. The biosynthesis of valine, leucine, and isoleucine as well as the metabolism of alanine, aspartic acid, and glutamic acid were the major routes that led to the identification of 1385 non-volatile components in total. This study offers a theoretical foundation for industrial development and advances our knowledge of the fundamental mechanism underlying flavor generation during LPCW fermentation.

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