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Antibiotic-induced dysbiosis in the fish gut causes significant adverse effects. We use fecal microbiota transplantation (FMT) to accelerate the restoration of florfenicol-perturbed intestinal microbiota in koi carp, identifying key bacterial populations and metabolites involved in the recovery process through microbiome and metabolome analyses. We demonstrate that florfenicol disrupts intestinal microbiota, reducing beneficial genera such as Lactobacillus, Bifidobacterium, Bacteroides, Romboutsia, and Faecalibacterium, and causing mucosal injuries. Key metabolites, including aromatic amino acids and glutathione-related compounds, are diminished. We show that FMT effectively restores microbial populations, repairs intestinal damage, and normalizes critical metabolites, while natural recovery is less effective. Spearman correlation analyses reveal strong associations between the identified bacterial genera and the levels of aromatic amino acids and glutathione-related metabolites. This study underscores the potential of FMT to counteract antibiotic-induced dysbiosis and maintain fish intestinal health. The restored microbiota and normalized metabolites provide a basis for developing personalized probiotic therapies for fish. Analysis of microbiome and metabolome reveals that fecal microbiota transplantation accelerates the restoration of florfenicol-disturbed gut microbiota in koi carp and identifies key microbial taxa and metabolites involved in this recovery process. [ABSTRACT FROM AUTHOR]

Polyetheretherketone (PEEK), with good biocompatibility and similar mechanical properties to natural bone, is extensively employed in the manufacture of prostheses. However, the precision and mechanical properties of current implants are major challenges for clinical applications. In this study, the effect of pore size, raster angle and printing temperature were investigated on length, width, thickness, material consumption, compressive strength and Young's modulus. Taguchi design of experiment method was used to reduce the number of experiments and optimize the printing process parameters. Finally, predictive analysis was exploited to give the optimal set of process parameters. Experimental results indicated that the approach applied in this work provided more accurate predictions and control of the response variables. The maximum compressive strength and compressive modulus of PEEK scaffolds reached 43.4 MPa and 253.3 MPa, respectively. Therefore, the methodology of present work has the potential to meet the demand of design precision and manufacture of customized bone substitutes. [ABSTRACT FROM AUTHOR]

In this study, Penaeus monodon were gave basic feed supplemented with three levels of Enterococcus faecium. Then, the expression of non-specific immunity-related genes, and the activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), malondialdehyde (MDA), acid phosphatase (ACP), alkaline phosphatase (AKP), phenol oxidase (PO) were evaluated. Meanwhile, the disease resistance test and intestinal flora determination were conducted. The results showed that the MDA levels of 2% and 5% E. faecium groups were significantly lower than that of the control group (P < 0.05). While the SOD and T-AOC and ACP and AKP of experimental groups were significantly higher (P < 0.05), the PO of experimental groups were significantly lower than that of the control group (P < 0.05). In addition, the expressions of immunity-related genes (tlr22, dorsal, lysozyme, crustin, imd, and relish) in the 2% and 5% E. faecalis groups were significantly greater than those in the control group (P < 0.05). After P. monodon was challenged with Vibrio parahaemolyticus for 7 days, the average cumulative mortality of P. monodon in the 2% and 5% groups were significantly lower than that in the 0% group (P < 0.05). With the increase of feeding time, the number of effective OTUs in each group showed a downward trend. At the 14th d, Proteobacteria, Bacteroidetes and Firmicutes, the dominant flora in the intestinal tract of P. monodon. In summary, supplied with E. faecium could increase the expression of non-specific immunity-related genes, enhance the immune capacity of P. monodon. [ABSTRACT FROM AUTHOR]

An acute infectious disease of northern sheatfish (Silurus soldatovi) was found in a commercial aquaculture pond in Tianjin, China. Herein, two dominant bacterial strains were isolated from naturally diseased northern sheatfish and identified as Aeromonas veronii and Vibrio cholerae. Seven healthy and seven naturally diseased fish that were collected from the pond were used for the gut microbiota analysis by high‐throughput 16S rRNA gene sequencing. The α‐diversity indices (ACE, Chao 1, and Shannon) did not differ significantly between diseased and healthy fish (p > 0.05), but a significant separation was observed between them when β‐diversity analysis of the bacterial population was performed. The diseased fish demonstrated a significant elevation in the relative abundances of Aeromonas, Vibrio, Blautia, and Megamonas and a decrease in Cetobacterium, Bacteroides, Chryseolinea, Ralstonia, and Pseudomonas compared with healthy fish (p < 0.05). Linear discriminant analysis effect size showed that microbial marker species in the diseased fish were in the order Aeromonadales, the family Aeromonadaceae, and the genus Aeromonas. The functional profiles of the microbial community that were predicted using the PICRUSt2 indicated that the disturbance of gut microbiota caused the alteration of its functional profiles in the diseased fish. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA), a biodegradable polymer, has become a major raw material in the field of 3D printing. However, some defects such as high brittleness and average bioactivity limit its application. In this study, a novel 3D printing composite of animal bone powder/polyethylene glycol/polylactic acid was prepared and investigated. The structures and properties of bHA/PEG/PLA composites were compared with commercial micron‐sized hydroxyapatite (mHA) and nano hydroxyapatite (nHA) composites. The study results show that the bHA has the same chemical structure as mHA and nHA, but its average particle size is 390 nm, which is quite different from mHA and nHA. When the PEG content is 14%, the toughness of the PEG/PLA blends is good, and its elongation at break reaches 96.23%. The bending strength, tensile strength, and elongation at break of bHA/PEG/PLA composites reach 25.1 MPa, 16.3 MPa, and 11.32%, respectively, which are all higher than those of mHA/PEG/PLA and similar to those of nHA/PEG/PLA. The bHA/PEG/PLA biological scaffolds prepared by 3D printing show good biocompatibility in cytotoxicity experiments and have good application prospects in bone tissue engineering. [ABSTRACT FROM AUTHOR]

In the Redclaw Crayfish, Cherax quadricarinatus, males grow larger and faster than females, and interest has focused on monosex breeding techniques for the production of males only. The adult male and female sexual characteristics of Cherax quadricarinatus are easily distinguished but cannot be determined in the embryo and juvenile stages. Because there is no DNA marker for the identification of sex in Cherax quadricarinatus, we sequenced its juvenile transcriptome in order to produce a reliable transcript to determine sex and to investigate its sex differentiation mechanisms at the molecular level. In this study, a female sex‐linked expression gene CqLRPPRC (Leucine‐rich PPR‐motif‐containing) of Cherax quadricarinatus was found in the transcriptome. Using semi‐quantitative RT‐PCR analysis, we found that the expression of the LRPPRC (leucine‐rich pentatricopeptide repeat cassette) gene was greater in the ovaries of females than in the testes of males, from the early juvenile stages onwards. Furthermore, in situ hybridization showed that the expression of its sexual dimorphism may be focused in the gonads. The results of an RNA interference treatment showed that a knockdown of CqLRPPRC up‐regulated the expression of vitellogenin (Vtg). The LRPPRC gene, and characteristic of shrimp, are reported here for the first time, and an assay of this gene can provide a molecular test to determine the sex of Cherax quadricarinatus in its different developmental stages, especially those during which no obvious sexual differences are visible. [ABSTRACT FROM AUTHOR]

Vibriotubiashii (Vt) infection is a common cause of severe diseases in aquaculture. In order to confirm the pathogenicity of Vt in ivory snail Babylonia areolata, the Vt strains were analyzed using isobaric tags for relative and absolute quantitation (iTRAQ) technology. Thus, 2717 proteins were identified. Fifty-three upregulated proteins and 52 downregulated proteins were found in the high-virulence strain (BBXP), compared with the low-virulence strain (FB13). The results suggested that the membrane proteins, such as type I secretion outer membrane protein, TolC, lipoprotein, efflux system proteins, iron-regulated protein A, and several virulence-associated proteins, were differentially regulated. Analysis of the different proteins showed that many were associated with quorum sensing regulation, and that there were significant differences between the highest-virulence strain and the lowest-virulence strain, including differences in their transcription factors, chemotaxis proteins, transport proteins, and proteins involved in iron homeostasis. Cell division proteins and cell repair proteins differed most significantly and the levels of these proteins in the virulent BBXP strain were much higher. The cell pathways related to stress responses and cell damage and the apoptosis pathways were significantly upregulated. This is the first study to identify differential proteins between Vt strains with different virulence levels. It will provide an important foundation for understanding the molecular mechanisms of the pathology of Vt in mollusks. [ABSTRACT FROM AUTHOR]

Pseudomonas alcaligenes infection is rare in aquaculture. In this study, we provide the first report on the characterization of P. alcaligenes from koi (a variant of Common Carp Cyprinus carpio) in China. A gram‐negative bacterium was isolated from the diseased koi and was named KCP‐516. Morphological and biochemical tests as well as phylogenetic tree analyses derived from 16S ribosomal RNA, gyrase subunit A, and gyrase subunit B gene sequencing all strongly indicated that the isolate KCP‐516 was P. alcaligenes. In liquid medium, the optimal growth conditions were 25°C, 2.5% NaCl, and pH 8. The pathogenicity of the isolate was demonstrated in koi, with 7.0 × 104 CFU/g fish weight identified as the dose lethal to 50% of test fish. The results will provide a scientific reference for the diagnosis and treatment of P. alcaligenes infection. [ABSTRACT FROM AUTHOR]

In this study, the delimitation of intestine segments of koi carp (Cyprinus carpio var. koi) was conducted using a histological approach with the measurements of height of mucosa folds (HF), width of mucosa folds (WF), thickness of muscularis (TM) and cross‐sectional area (CSA). According to the change trends for these four parameters, the intestine of the koi carp was divided into anterior intestine, middle intestine and posterior intestine. The locations of the three intestine segments were defined, and their ratios along the entire intestine were accounted for 23.84 ± 1.18%, 46.77 ± 2.29% and 29.39 ± 1.65%, respectively. The anterior intestine had a significantly higher HF, compared with the middle (p <.01) or posterior intestines (p <.01). The muscularis became thin gradually from the anterior intestine to posterior part. TM was significantly different among the anterior, middle and posterior intestines (p <.01). The anterior intestine had a significantly higher CSA, compared with the middle (p <.01) and posterior intestines (p <.01), and the latter two segments had similar CSA values (p >.05). The procedure of the delimitation of the koi carp intestine segments can offer useful information for future studies on other fish species. The presented results are meaningful for studies on differential functions of the different intestine segments in fish. [ABSTRACT FROM AUTHOR]

Providencia rettgeri infection has occurred occasionally in aquaculture, but is rare in turtles. Here, a pathogenic P. rettgeri strain G0519 was isolated from a diseased slider turtle (Trachemys scripta) in China, and qPCR assay was established for the RTX toxin (rtxD) gene. Histopathological examination showed that many inflammatory cells were infiltrated into heart, liver and intestine, as well as the necrosis of liver, kidney and spleen. The genome consisted of one circular chromosome (4.493 Mb) and one plasmid (18.8 kb), and predicted to contain 4170 and 19 protein-coding genes, respectively. Multiple pathogenic and virulence factors (e.g., fimbria, adhesion, invasion, toxin, hemolysin, chemotaxis, secretion system), multidrug-resistant genes (e.g., ampC, per-1, oxa-1, sul1, tetR) and a novel genomic resistance island PRI519 were identified. Comparative genome analysis revealed the closest relationship was with P. rettgeri, and with P. heimbachae closer than with other Providencia spp. To our knowledge, this was first report on genomic characterization of multidrug-resistant pathogenic P. rettgeri in cultured turtles. [ABSTRACT FROM AUTHOR]

Crucian carp (Carassius auratus) is one of the major freshwater species and important food fish in China. Fish skin acts as the first line of defence against pathogens, yet its molecular and immune mechanism remains unclear. In this study, a de novo transcriptome assembly of C. auratus skin was performed with the Illumina Hiseq 2000 platform. A total of 49,154,776 clean reads were assembled, among which 60,824 (46.86%), 37,103 (28.59%), 43,269 (33.33%) unigenes were annotated against National Center for Biotechnology Information, Gene Onotology and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively. KEGG Orthology categories were significantly involved in immune system (20.50%), signal transduction (18.04%) and mucosal mucin genes (e.g., muc2, muc5AC, muc5B, muc17, muc18). The high expression of muc18 gene was observed in brain; that of muc2 in intestine; and that of muc5AC in skin, liver, spleen, intestine and muscle. Moreover, the potential 28,928 simple sequence repeats with the three most abundant dinucleotide repeat motifs (AC/GT, AG/CT, AT/AT) were detected in C. auratus. To authors' knowledge, this is the first report to describe the transcriptome analysis of C. auratus skin, and the outcome of this study contributed to the understanding of mucosal immune response of the skin and molecular markers in cyprinid species. [ABSTRACT FROM AUTHOR]

Rahnella aquatilis is an important pathogen of several aquatic organisms and is found widely distributed in the freshwater, soil, fish and human clinical samples. Our previously published study reported a novel pathogenic R. aquatilis strain KCL‐5 to crucian carp (Carassius auratus). To further investigate the characteristics and pathogenesis caused by R. aquatilis, we here report on the pathological changes, bacterial genomic and proteomic analyses of strain KCL‐5. Significantly pathological changes in liver, intestine, spleen and gills were observed in infected fish. The genome consists of one circular chromosome 5,062,299 bp with 52.02% GC content and two plasmids (506,827 bp, 52.16%; 173,433 bp, 50.00%) and predicted 5,653 genes, 77 tRNAs and 22 rRNAs. Some virulence factors were characterized, including outer membrane protein, haemolysin, RTX toxin, chemotaxis and T3SS secretion system. Antimicrobial resistance genes such as EmrAB‐TolC, MexABC‐OpmB and RosAB efflux pump were found in strain KCL‐5. KEGG analysis showed that mainly functional modules were ABC transporters, biosynthesis of amino acids, two‐component system, quorum sensing, flagellum assembly and chemotaxis, in which most of them were identified by using 2‐DE/MS analyses. To our knowledge, this was first report on the molecular characteristics of R. aquatilis by multi‐omics approaches, which will provide insights into the pathogenic mechanism of R. aquatilis infection in fish. [ABSTRACT FROM AUTHOR]

Aeromonas salmonicida is one of the most important pathogens in salmonids and non-salmonids species. Nevertheless, very little was reported in cyprinids about A. salmonicida infection. Hence, a pathogenic A. salmonicida subsp. salmonicida, namely isolate GCA-518, was isolated from diseased crucian carp Carassius auratus. Its optimal growth conditions were at 28 °C, pH 7.0 and 1.5% NaCl. Furthermore, the quantitative real-time PCR (qPCR) targeting serine protease (aspA) gene was established for rapid detection of the lowest limit of 5.6 × 102 copies per reaction. The pathogenicity was confirmed in crucian carp by intraperitoneal infection. Histopathologic examination displayed multifocal necrosis and infiltration of inflammatory cells in gill, liver, kidney and intestine. This is the first report on typical A. salmonicida infection in cultured crucian carp. [ABSTRACT FROM AUTHOR]

In the present study, a Gram-positive bacterium was isolated from the intestine of healthy crucian carp Carassius auratus and named strain R8. It was initially identified as Enterococcus faecium according to its morphological, physiological and biochemical characteristics. Further identification by using 16S rRNA gene sequence analysis confirmed the R8 strain (Genbank accession no. MF928076) as E. faecium. Challenge and hemolysis experiments showed that the E. faecium R8 strain had no toxicity to the crucian carp. Bacteriostatic experiment showed that this isolate obviously inhibited the growth of Aeromonas veronii and Staphylococcus haemolyticus. The proliferation of E. faecium R8 strain occurred after exposure to various growth conditions such as at pH values from 2.0 to 4.0 for 8 h, bile concentrations from 0.2 to 1.2% and high temperature of 80 °C. This bacterial strain grew best under the condition of 37 °C, pH 7.0 and salinity 30 ppt, and its growth curve exhibited four distinct phases. These results showed that the E. faecium R8 strain had potential probiotic characteristics and could be used as a candidate strain for aquatic probiotics. [ABSTRACT FROM AUTHOR]

Aeromonas species often cause disease in farmed fish. In the present study, dominant bacteria were isolated from diseased crucian carp (Carassius auratus gibelio). Based on this, a bacterial isolate was tentatively named CFJY-623. This isolate was identified as Aeromonas veronii based on analysis of its morphological, physiological, and biochemical features, as well as 16S rRNA and gyrB gene sequences. Six virulence genes related to pathogenicity including aerolysin, cytotonic enterotoxins, elastase, glycerophospholipid: cholesterol acyltransferase, lipase, and serine protease were identified in this A. veronii isolate. The median lethal dosage (LD50) of the CFJY-623 isolate for crucian carp was determined as 1.31 × 107 CFU/mL. Artificial experimental infection showed that the CFJY-623 isolate caused considerable histological lesions in the fish, including tissue cell degeneration, necrosis, and inflammatory cell infiltrating. Drug sensitivity testing showed that the isolate was susceptible to aminoglycosides, carbapenemes, and nitrofurans. Exploring its growing features showed that this isolate exhibited a high level of environmental adaptability. These results provided a scientific basis for the identification of A. veronii and treatment for fish infected by this pathogen. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to investigate the distribution of acid phosphatase (ACP), alkaline phosphatase (ALP), non-specific esterase (NSE), peroxidase (POD), and mucous cells in the intestine of the koi carp Cyprinus carpio var. koi. ACP activity was located in the striated border, enterocytes, and lamina propria of the anterior and middle intestines. The ACP activity in the anterior intestine was higher than that in the middle and posterior intestines. ALP existed in the striated border of enterocytes and lamina propria, serosa, muscular layer, and the junction between muscular layer and submucosa layer of the intestine. The ALP activity in the anterior intestine was higher than that in the middle and posterior intestines. NSE activity was localized in the cytoplasm of enterocytes in the whole intestine, and the middle intestine showed the lower NSE activity than the anterior and posterior intestines. POD activity was localized in the blood cells of the lamina propria and cytoplasm of enterocytes in all intestinal segments. The POD activity among the anterior, middle, and posterior intestines was non-significantly different. Alcian blue periodic acid–Schiff histochemical results revealed three types of mucous cells in the intestine. The total number of mucous cells and percentage of type I cells among the anterior, middle, and posterior intestines were non-significantly different. The percentage of the type II cells was the highest in the posterior intestine, while the lowest in the anterior intestine. The percentage of the type III cells was the highest in the anterior intestine, while the lowest in the posterior intestine. [ABSTRACT FROM AUTHOR]

The influence of magnetic matrices, magnetic field intensity, secondary and three section superconducting magnetic separation on the separation was studied in this paper. The magnetic field and flow field characteristics of elliptic cross-section matrix were studied in the elliptic coordinate system. The motion equations of the magnetic particles were derived. The tests results show that molybdenum concentrate with Mo grade of 7.4% and recovery of 43.6%, copper concentrate with Cu grade of 33.0% and recovery of 93.5% could be obtained, which verified the feasibility of separating copper-molybdenum by superconducting magnetic separation. [ABSTRACT FROM AUTHOR]

Background Yellowhorn (Xanthoceras sorbifolium Bunge), a deciduous shrub or small tree native to north China, is of great economic value. Seeds of yellowhorn are rich in oil containing unsaturated long-chain fatty acids that have been used for producing edible oil and nervonic acid capsules. However, the lack of a high-quality genome sequence hampers the understanding of its evolution and gene functions. Findings In this study, a whole genome of yellowhorn was sequenced and assembled by integration of Illumina sequencing, Pacific Biosciences single-molecule real-time sequencing, 10X Genomics linked reads, Bionano optical maps, and Hi-C. The yellowhorn genome assembly was 439.97 Mb, which comprised 15 pseudo-chromosomes covering 95.42% (419.84 Mb) of the assembled genome. The repetitive fractions accounted for 56.39% of the yellowhorn genome. The genome contained 21,059 protein-coding genes. Of them, 18,503 (87.86%) genes were found to be functionally annotated with ≥1 "annotation" term by searching against other databases. Transcriptomic analysis showed that 341, 135, 125, 113, and 100 genes were specifically expressed in hermaphrodite flower, staminate flower, young fruit, leaf, and shoot, respectively. Phylogenetic analysis suggested that yellowhorn and Dimocarpus longan diverged from their most recent common ancestor ∼46 million years ago. Conclusions The availability and subsequent annotation of the yellowhorn genome, as well as the identification of tissue-specific functional genes, provides a valuable reference for plant comparative genomics, evolutionary studies, and molecular design breeding. [ABSTRACT FROM AUTHOR]

Based on the established equivalent circuit model of a magnetostrictive vibration generator, the low ac voltage and low power produced by the generator under low acceleration are calculated. Comparisons between the calculated and measured results show that the model can provide reasonable data trends of the generator under different loads. To boost the low ac voltage to a high dc voltage required by electronic devices in low power consumption, two energy extraction circuits (EECs) (i.e., a proportion integration-based EEC and an improved EEC) are studied. The corresponding two harvesting systems, which include the generator and the proposed EECs, are designed and simulated in LTspice for system-level evaluation. It is found that the two harvesting systems can effectively boost a few hundred millivolts of ac voltage to the steady dc voltage under low acceleration and varying load conditions. Moreover, the system with the improved EEC can be powered by the harvested energy to maintain self-sustaining operation, and the batteries in the system can be charged for future start-up operations; thus, the system has strong practicability in the dc supply for the electronic devices. [ABSTRACT FROM AUTHOR]

The potential energy curves (PECs) of 24 Λ–S electronic states of superoxide anion (O2−), which correlated with the first dissociation channel, were calculated using a high-accuracy internally contracted multireference configuration interaction (icMRCI) methodology with the Davidson correction in conjunction with the correlation-consistent basis sets. The core electron correlation and scalar relativistic corrections as well as basis set extrapolation were included. The spin–orbit coupling was also taken into account by using the state interaction approach with the Breit–Pauli Hamiltonian. The PECs of 54 Ω states generated from the 24 Λ–S states were constructed and described in detail. The spectroscopic constants of the seventeen Λ–S and 37 Ω bound states were evaluated and the vibrational properties of some weakly bound states were predicted. Comparing with the available experimental and theoretical data shows that the computational strategy employed is suitable and highly accurate for this system. [ABSTRACT FROM AUTHOR]

Background: The purpose of the present study was to evaluate the efficacy of extended pancreatoduodenectomy (EPD) and standard pancreatoduodenectomy (SPD) for ductal adenocarcinoma of the head of the pancreas via meta-analysis. Methods: Relevant articles (published between 1995 and 2012) were compiled from online data sources. A total of nine studies satisfied the selection criteria, including a total of 973 patients (478 in the SPD group and 495 in the EPD group). Evaluation parameters included 1-, 3-, and 5-year survival, as well as mortality, morbidity, and specific morbidity outcomes. Results: Meta-analysis revealed (1) differences in morbidity (Odds ratio [OR] = 1.740; 95 % confidence interval [CI], 0.840-3.600; P = 0.140), mortality (OR = 0.890; 95 % CI, 0.560-1.400; P = 0.620), 1-year overall survival (OS) rate (OR = 1.20; 95 % CI, 0.490-2.930; P = 0.69), 3-year OS rate (OR = 0.770; 95 % CI, 0.460-1.280; P = 0.190), and 5-year OS rate (OR = 1.12; 95 % CI, 0.690-1.810; P = 0.560) were not significant between EPD and SPD. (2) For bile leak (OR = 2.640; 95 % CI, 1.040-6.700; P = 0.040), pancreatic leak (OR = 1.740; 95 % CI, 1.040-2.91; P = 0.030), delayed gastric emptying (OR = 2.090; 95 % CI, 1.240-3.520; P = 0.006), and lymphatic fistula (OR = 6.120; 95 % CI, 1.06-35.320; P = 0.040) differences between EPD and SPD were significant, whereas other specific morbidities were not significantly different. Conclusions: Extended pancreatoduodenectomy does not improve 1-, 3-, 5-year OS rates compared to SPD and there is a trend toward increased bile leak, pancreatic leak, delayed gastric emptying, and lymphatic fistula after EPD. [ABSTRACT FROM AUTHOR]

Liver transplantation is an established therapy for end-stage liver diseases. Graft rejection occurs unless the recipient receives immunosuppression after transplantation. This study aimed to explore the mechanism of acute rejection of liver allografts in rats pre-treated with total body irradiation to eliminate passenger lymphocytes and to define the role of CD4CD25 regulatory T cells in the induction of immunotolerance in the recipient. Male Lewis rats were used as donors and male DA rats were recipients. Rats were randomly assigned to the following four groups: control group, homogeneity liver transplantation group, idio-immunotolerance group and acute rejection group. After transplantation, the survival time of each group, serum alanine aminotransferase, total bilirubin levels, number of Foxp3CD4CD25 regulatory T cells, expression of glucocorticoid-induced tumor necrosis factor receptor on T cell subgroups, histopathology of the hepatic graft and spleen cytotoxic T lymphocyte lytic activity were measured. In the acute rejection group, where donors were preconditioned with total body irradiation before liver transplantation, all recipients died between day 17 and day 21. On day 14, serum alanine aminotransferase increased significantly to (459.2±76.9) U L, total bilirubin increased to (124.1±33.7) μmol L ( P<0.05) and the ratio of Foxp3CD4CD25 regulatory T cells decreased significantly to 1.50%±0.50% ( P<0.05) compared with the other groups. Analysis of the T cell subpopulations in the acute rejection group varied from the other groups. Histological analysis showed typical changes of acute rejection in the acute rejection group only. Preconditioning of the donors with total body irradiation eliminated passenger lymphocytes of the liver graft, and thus affected the course of tolerance and induced acute rejection after liver transplantation. [ABSTRACT FROM AUTHOR]

The effect of phosphatidylcholine on the molecular weight properties of hyaluronic acid (HA) was studied in batch culture of Streptococcus zooepidemicus by adding phosphatidylcholine at the early stage of exponential phase. With the addition of 80 mg/L of phosphatidylcholine, maximum HA yield (2.47 g/L) and weight-average molecular weight (902.60 KDa) were achieved, increased by 17.4% and 67.1%, respectively, as compared to the control. Metabolic flux analysis was employed to study the mechanism of phosphatidylcholine on the molecular weight of HA. The normalized flux distribution maps based on fermentation data at phosphatidylcholine addition indicated that phosphatidylcholine resulted in higher flux flowing to the HA pathway and lower flux flowing to the glycolysis and biomass synthesis pathway, coupling with higher level of UDPNAG generation and extra regeneration of ATP. The GC-MS analysis of fatty acids in the plasma membrane showed that the addition of phosphatidylcholine could promote the mobility and permeability of the cell membrane, making the HA chain pass through the membrane more easily, thus decreasing the energy consumption. All these results led to higher molecular weight of hyaluronic acid. [ABSTRACT FROM AUTHOR]

The present paper studies the effects of precursor amino acids, i.e., l-glutamic acid (Glu), l-glycine (Gly), and l-cysteine (Cys), on the glutathione (GSH) production. The three amino acids were added during the fermentations. The GSH production was analyzed by gas chromatography-mass spectrometry (GC-MS). It was observed that the cell content of Cys reduced continually, Gly maintained a fairly constant concentration, while Glu remained at a high concentration compared with Cys and Gly. The synthesis of GSH was found to significantly increase after 28 h of fermentation upon addition of 6 mmol l of each of the three amino acids. Under these conditions, the GSH yields reached 2,250 ± 50 mg l at 34 h from 1,050 ± 50 mg l at 28 h. The GC-MS analyses on the effect caused by the addition of amino acids indicated that the addition of Glu was not necessary to improve the GSH production by high-cell-density cultivation of Saccharomyces cerevisiae. The addition of Cys or Gly individually enhances the production of GSH. [ABSTRACT FROM AUTHOR]

Reduced cellular immune function in patients after liver transplantation easily results in many types of viral infections, such as Epstein-Barr virus. Epstein-Barr virus is a Γ-herpesvirus and is related to many malignant diseases, especially epithelial and lymph tumors. The abnormal interaction of cluster of differentiation 40 with cluster of differentiation 40 ligand and expression of cluster of differentiation 40 ligand are considered closely related to the development of myeloma cells. This study explored the influence and mechanism of Epstein-Barr virus infection on the phenotype and biological behavior of myeloma cells after liver transplantation. Flow cytometry was used to detect coexpression of cluster of differentiation 40 and cluster of differentiation 40 ligand in 10 samples of freshly isolated multiple myeloma cells. Cluster of differentiation 40 and cluster of differentiation 40 ligand were coexpressed in sample Nos. 5, 8, 9, and 10, particularly in sample No. 5. Western blot analysis was used to detect the expression of the Epstein-Barr virus antigens latent membrane protein 1 and Epstein-Barr virus nuclear antigen 2 in the multiple myeloma cell line RPMI 8226 infected with Epstein-Barr virus. The antigen expression indicated that Epstein-Barr virus can infect multiple myeloma virus cells in vitro. Reverse transcription-polymerase chain reaction revealed upregulated expression of cluster of differentiation 40 ligand on the infected RPMI 8226 cells, which may be involved in the anti-apoptosis activity of the infected cells. Confocal microscopy showed that pairs of molecules of cluster of differentiation 40, cluster of differentiation 40 ligand, and latent membrane protein 1 were colocalized on the surface of the infected cells. CXC chemokine receptor 4 was upregulated on the RPMI 8226 cells after Epstein-Barr virus infection. The migratory ability of the infected cells improved in the presence of the chemokine stromal cell-derived factor-1α. Anti-apoptosis and migration are known important biological characteristics of malignant cells. Our results indicate the involvement of Epstein-Barr virus in the origin and development of multiple myeloma. The risk of multiple myeloma increases when Epstein-Barr virus infects B cells in the germinal center, which may result in an anti-apoptosis effect of B cells and an improved ability to migrate from the germinal center to peripheral blood. [ABSTRACT FROM AUTHOR]

A modified genomic DNA extraction method named the combination of lysozyme and ultrasonic lysis (CLU) method was used to analyze the fish intestinal microflora. In this method, the physical disruption and chemical lysis steps were combined, and some parameters in the key steps were adjusted. In addition, the results obtained by this method were compared with the results obtained by the Zirmil-beating cell disruption method and the QIAamp Fast DNA Stool Mini Kit. The OD260/OD280 ratio and concentration of the DNA extracted using the CLU method were 2.02 and 282.8 µg/µL, respectively; when the incubation temperatures for lysozyme and RNase were adjusted to 37 °C, those values were 2.08 and 309.8 µg/µL, respectively. On the agarose gel, a major high-intensity, discrete band of more than 10 kb was found for the CLU method. However, the smearing intensity of degraded DNA was lower when the incubation temperatures were 60 °C for lysozyme and 30 °C for RNase than when incubation temperatures of 37 °C for lysozyme and 37 °C for RNase were used. The V3 variable region of the prokaryotic 16S rDNA was amplified, and an approximately 600-bp fragment was observed when the DNA extracted using the CLU method was used as a template. The CLU method is simple and cost effective, and it yields high-quality, unsheared, high-molecular-weight DNA, which is comparable to that obtained with a commercially available kit. The extracted DNA has potential for applications in critical molecular biology techniques. [ABSTRACT FROM AUTHOR]