[Antibacterial effect of low-temperature plasma on Enterococcus faecalis in dentinal tubules in vitro].

OBJECTIVE: To construct a model of Enterococcus faecalis (E. faecalis) infection in dentinal tubules by gradient centrifugation and to evaluate the antibacterial effect of low-temperature plasma on E. faecalis in dentinal tubules. METHODS: Standard dentin blocks of 4 mm×4 mm×2 mm size were prepared from single root canal isolated teeth without caries, placed in the E. faecalis bacterial solution, centrifuged in gradient and incubated for 24 h to establish the model of dentinal tubule infection with E. faecalis. The twenty dentin blocks of were divided into five groups, low-temperature plasma jet treatment for 0, 5 and 10 min, calcium hydroxide paste sealing for 7 d and 2% chlorhexidine gel sealing for 7 d. Scanning electron microscopy and confocal laser scanning microscope were used to assess the infection in the dentinal tubules and the antibacterial effect of low-temperature plasma. RESULTS: The results of scanning electron microscopy and confocal laser scanning microscopy showed that after 24 h of incubation by gradient centrifugation, E. faecalis could fully enter the dentinal tubules to a depth of more than 600µm indicating that this method was time-saving and efficient and could successfully construct a model of E. faecalis infection in dentinal tubules. Low-temperature plasma could enter the dentinal tubules and play a role, the structure of E. faecalis was still intact after 5 min of low-temperature plasma treatment, with no obvious damage, and after 10 min of low-temperature plasma treatment, the surface morphology of E. faecalis was crumpled and deformed, the cell wall was seriously collapsed, and the normal physiological morphology was damaged indicating that the majority of E. faecalis was killed in the dentinal tubules. The antibacterial effect of low-temperature plasma treatment for 10 min exceeded that of the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d. These two chemicals had difficulty entering deep into the dentinal tubules, and therefore only had a few of antibacterial effect on the bacterial biofilm on the root canal wall, and there was also no significant damage to the E. faecalis bacterial structure. CONCLUSION: Gradient centrifugation could establish the model of E. faecalis dentin infection successfully. Low-temperature plasma treatment for 10 min could kill E. faecalis in dentinal tubules effectively, which is superior to the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d.

[Clinicopathological features and prognosis of primary mediastinal large B-cell lymphoma: a series of sixty cases].

Objective: To investigate the clinicopathological features and prognostic factors of primary mediastinal large B-cell lymphoma (PMBL). Methods: The clinical data of 60 patients with PMBL including 44 biopsy cases and 16 consultation cases from September 2000 to November 2019 in the Department of Pathology, China-Japan Friendship Hospital (14 cases) and Peking Union Medical College Hospital (46 cases) were enrolled. Pathologic features, immunophenotype, immunoglobulin (Ig) gene rearrangement and microRNA expression profile were retrospectively studied. Results: Of the 60 patients, 23 were males and 37 were females, age ranged from 15 to 64 years (median 28 years). Immunohistochemical staining showed that the tumor cells were positive for pan-B cell antigens, CD30 (77.4%, 24/31), CD23 (73.1%, 19/26), MUM1 (45.8%, 11/24), Ki-67 index ≥70 % (90.6%, 29/32). EBER in situ hybridization was analyzed in 21 PMBL, only one case (4.8%) was positive. Ig gene rearrangement was performed in 20 cases, and seven were positive (35.0%). MicroRNA gene expression profiles were analyzed in seven cases of PMBL and nine cases of diffuse large B-cell lymphoma, and there were 33 microRNAs with significant difference (P<0.05). Univariate analysis indicated that the poor prognostic factors included serum lactate dehydrogenase (LDH) level,International Prognostic Index (IPI) score ≥3, stages Ⅲ-Ⅳ, chemotherapy not combined with rituximab and MUM1 positivity (P<0.05). Multivariate analysis showed that the treatment combined with rituximab was independently related to prognosis (P<0.05). Conclusions: PMBL is different from diffuse large B-cell lymphoma in clinicopathologic features, immunophenotypic presentation and molecular features. The prognostic factors, molecular genetics and immunological characteristics reveal that this study has enriched our understanding of the biology of PMBL, thus providing evidence and strategies for treatment.

Long-term chemically protected sodium butyrate supplementation in broilers as an antibiotic alternative to dynamically modulate gut microbiota.

Chemically protected sodium butyrate (CSB) is a new kind of sodium butyrate. Our previous study found that 1,000 mg/kg of CSB had the potential capacity of improving growth performance and promoting early development of small intestine in broilers. This study aimed to investigate the effect of long-term antibiotics or CSB supplementation for intestinal microflora dynamical regulation in broilers. One hundred ninety-two 1-day-old Arbor Acres male broilers were randomly allocated into 3 dietary treatment (8 replicates per treatment) and fed with a basal diet (CON), a diet supplemented with the antibiotics (enramycin, 8 mg/kg and aureomycin, 100 mg/kg) (ANT), or a diet supplemented with 1,000 mg/kg of CSB, respectively. Results showed that dietary supplementation of CSB or ANT treatment elevated the weight gain and feed conversion ratio (FCR; P < 0.05), as compared with control (CON) group. Additionally, CON, CSB, or ANT administration dynamically altered the gut microbiota composition as time goes on. The increased presence of potential pathogens, such as Romboutsia and Shuttleworthia, and decreased beneficial bacteria such as Alistipes, Akkermansia, and Bacteroides were verified in new gut homeostasis reshaped by long-term antibiotics treatment, which has adverse effects on intestinal development and health of broilers. Conversely, CSB supplementation could dynamically enhance the relative abundance of Bacteroides, and decrease Romboutsia and Shuttleworthia in new microflora, which has positive effects on intestinal bacteria of broilers compared with CON group. Meanwhile, CSB supplementation was significantly increased the concentration of propionic acid and total short chain fatty acids (total SCFA; P < 0.05) in comparison with CON and ANT groups. Moreover, CSB treatment significantly increased anti-inflammatory and antioxidative capacities (P < 0.05) of broilers compared with ANT group. Taken together, we revealed characteristic structural changes of gut microbiota throughout long-term CSB or ANT supplementation in broilers, which provided a basic data for evaluating the mechanism of action affecting intestinal health by CSB or ANT administration and CSB as an alternative to antibiotics in the broilers industry.

[Epigenetic regulation in tooth development].

Epigenetics refers to genetic regulation patterns that gene expressions, which lead to the phenotype variance, are modified in the absence of changes of DNA sequence. Epigenetics mainly includes DNA methylation, histone modification, and non-coding RNA regulation. During the development of the teeth, conventional gene regulation and epigenetics synergistically regulate the spatial and temporal expression of genes, which involved in cell proliferation, differentiation and finally the formation of teeth. Exploration of the epigenetic regulation mechanisms during tooth development can provide multiple clues and ideas for the research of tooth regeneration. This article reviewed the significant roles of epigenetic regulation in tooth development.

Relationship between red blood cell distribution width, bilirubin, and clinical characteristics of patients with gastric cancer.

INTRODUCTION: Red blood cell distribution width (RDW) and bilirubin have been proved to be prognostic factors for various types of cancer. However, their prognostic value in patients with gastric cancer (GC) remains largely unknown. METHODS: To verify whether RDW and bilirubin are prognostic factors for patients with GC, we performed a cross-sectional study to analyze the relationship between RDW, bilirubin, and the clinical characteristics of patients with GC. Medical records of all newly diagnosed and pathologically proved patients with GC admitted to Changzheng Hospital between January 2016 and July 2016 were retrospectively reviewed. The relationship between RDW, bilirubin, and the clinical characteristics of patients with GC was analyzed. RESULTS: A total of 144 patients with GC were enrolled. Patients with GC had significantly higher RDW than healthy controls, even after adjusting for hemoglobin, while total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) were significantly decreased. Furthermore, RDW and bilirubin were significantly correlated with tumor stage, as well as carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9). CONCLUSION: Our study indicated that RDW and bilirubin could be potential prognostic factors for patients of GC.

Viscous and fermentable nonstarch polysaccharides affect intestinal nutrient and energy flow and hindgut fermentation in growing pigs.

Two experiments were conducted to determine the effects of viscosity and fermentability of purified nonstarch polysaccharides (NSP) on intestinal nutrient and energy flow and hindgut fermentation in growing pigs. In Exp. 1, 15 ileal-cannulated pigs (50.5 ± 2.9 kg BW) were allotted to 5 diets in a 2-period incompletely randomized design. Pigs were provided a cornstarch N-free diet (CST) or a diet containing 5% inulin (INU), carboxymethylcellulose sodium (CMC), microcrystalline cellulose (MCC), or Solka-Floc (SFC). Apparent ileal digestibility (AID) of DM, ash, and GE were greater ( < 0.05) in the MCC and SFC diets than in the INU and CMC diets. Apparent total tract digestibility (ATTD) of DM, carbohydrates (CHO), and GE and the DE content in the CST and INU diets were greater ( < 0.01) than in the CMC, MCC, and SFC diets. Hindgut disappearance of DM, CHO, and GE in the INU diet was greater ( < 0.05) than in the other N-free diets. The ileal endogenous flow of His, Ile, Leu, Met, Thr, Val, and all dispensable AA in the CMC diet was greater ( < 0.05) than in the other diets. In Exp. 2, 6 ileal-cannulated pigs were allotted to 3 diets containing either a corn-soybean meal control diet or the control diet with 5% INU or CMC in a replicated 3 × 3 Latin square design. Standardized ileal digestibility (SID) of Ala, Arg, Asp, Cys, Gly, His, Ile, Leu, Lys, Phe, Ser, Thr, and Val were greater ( < 0.05) in the CMC diet than in the control and INU diets. Incorporation of 5% INU or CMC in the control diet reduced ( < 0.01) the AID of arabinoxylan and insoluble and total NSP. The ATTD of NSP and cellulose and the hindgut disappearance of NSP, ß-glucan, and cellulose in the CMC diet were less ( < 0.01) than in the control and INU diets. Inclusion of 5% INU in the diet increased ( < 0.01) hindgut fermentation of insoluble and total NSP compared with the control and CMC diets. In conclusion, depending on the viscosity and fermentability of the NSP, different sources will have different effects on nutrient digestibility and hindgut fermentation. Addition of 5% INU to a corn-soybean meal diet reduced digestibility of the NSP component in the ileum and increased hindgut fermentation of total NSP. In contrast, the inclusion of CMC increased the AID and SID of the diet and reduced total tract digestion and hindgut fermentation of NSP component. Carboxymethylcellulose sodium is not recommended as a source of synthetic fiber in a N-free diet to determine the SID of AA of diets.

Effects of feeding transgenic corn with mCry1Ac or maroACC gene to laying hens for 12 weeks on growth, egg quality and organ health.

The objective of the present study was to investigate the effect of feeding two transgenic corn lines containing the mCry1Ac gene from Bacillus thuringiensis strain (BT-799) and the maroACC gene from Agrobacterium tumefaciens strain (CC-2), respectively, on growth, egg quality and organ health indicators. Expression of the mCry1Ac gene confers resistance to Pyrausta nubilalis and the maroACC gene confers tolerance to herbicides. Healthy hens (n=96 placed in cages; 3 hens/cage) were randomly assigned to one of four corn-soybean meal dietary treatments (8 cages/treatment) formulated with the following corn: non-transgenic near-isoline control corn (control), BT-799 corn, CC-2 corn and commercially available non-transgenic reference corn (reference). The experiment was divided into three 4-week phases (week 1 to 4, week 5 to 8 and week 9 to 12), during which hens were fed mash diets. Performance (BW, feed intake and egg production) and egg quality were determined. Following slaughter at the end of 12 weeks of feeding (n=8/treatment), carcass yield and organ weights (heart, liver, spleen, lung, kidneys, stomach and ovary) were recorded; organs and intestines were sampled for histological analysis. Analysis of serum biochemistry parameters to assess the liver and kidney function were performed. No differences in BW, egg production and production efficiency were observed between hens consuming the control diet and hens consuming the BT-799 or CC-2 diet. Haugh unit measures and egg component weights were similar between the control and test groups. Carcass yield was not affected by the diet treatment. Similar organosomatic indices and serum parameters did not indicate the characteristics of organ dysfunction. All observed values of the BT-799 and CC-2 groups were within the calculated tolerance intervals. This research indicates that the performance, egg quality, organ health and carcass yield of laying hens fed diets containing the BT-799 or CC-2 corn line were similar to that of laying hens fed diets formulated with the non-transgenic near-isoline corn with comparable genetic backgrounds.

Increased expression of Toll-like receptor 4 in peripheral blood leucocytes and serum levels of some cytokines in patients with ankylosing spondylitis.

Toll-like receptor 4 (TLR4) is a member of the Toll-like receptor family, which can bridge innate and adaptive immune responses. Activation of the TLR4 signalling pathway may induce the release of proinflammatory cytokines such as tumour necrosis factor (TNF)-alpha and interleukin (IL)-12, which was considered to play an important role in pathogenesis of immune-mediated diseases. Ankylosing spondylitis (AS) is an immune-mediated disease whose aetiology remains unknown. The aim of the study was to investigate the expression of TLR4 and serum TNF-alpha, IL-12 and soluble tumour necrosis factor-related apoptosis-inducing ligand (sTRAIL) level in AS patients. The results indicated that TLR4 protein and mRNA levels were significantly higher in AS patients than in healthy controls; however, there was no significant difference between human leucocyte antigen (HLA)-B27-positive and -negative AS patients, as well as serum levels of TNF-alpha, IL-12 and sTRAIL. In addition, in HLA-B27-positive AS patients, TLR4 level showed close associations with the cytokines and laboratory parameters of disease activity [erythrocyte sedimentation rate (ESR) and plasma C-reactive protein (CRP)], respectively. Similarly, the strong associations between the cytokines or between IL-12 and ESR or CRP were observed in HLA-B27-positive AS patients. Interestingly, in HLA-B27-positive AS patients, TNF-alpha correlated significantly with ESR, but did not with CRP. In contrast, sTRAIL correlated with CRP, but did not with ESR. Among HLA-B27-negative patients, no close correlation was found. In our study, it was suggested that the abnormal activation of TLR4 signalling and serum TNF-alpha, IL-12 and sTRAIL may play a key role in the development and progression of AS, which may be dependent on the status of HLA-B27 antigen.

The role of CD11c(+) hepatic dendritic cells in the induction of innate immune responses.

The role of the liver in the initiation and maintenance of tolerance is a critical immune function that involves multiple lineages of immune cells. Included within these populations are liver dendritic cells (DCs). Although there has been significant work on the phenotypic and functional roles of splenic and bone marrow dendritic cells, as well as their subsets, comparable studies in liver have often been difficult. To address this issue we have isolated, from C57BL/6 mice, relatively pure populations of DCs and compared phenotype and function to the data from spleen using flow cytometry, cell sorter assisted purification and culture, morphology by cytospin and May-Giemsa staining, cell cycle progression, antigen uptake, cytokine production and allo-activation potential. natural killer (NK)1.1(-)CD11c(+) liver DC subsets (conventional DCs, T cell receptor (TcR)beta(-)NK1.1(-)CD11c(+)B220(-) and plasmacytoid DCs, TcRbeta(-)NK1.1(-)CD11c(+)B220(+)) efficiently endocytose dextran and produce significant levels of tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and IL-12 p40 in response to Toll-like receptor (TLR) ligands, with responses higher than splenic DCs. There is also a differential capability of hepatic DCs to respond to innate signals. Indeed, CD11c(+) hepatic DCs have a greater capacity to respond to innate stimulation but are less capable of inducing CpG activated-allogeneic T cells. These data suggest that hepatic dendritic cells function as a critical bridge between innate and adaptive immunity and are capable of inducing stronger innate responses with a lower capacity for allo-stimulation than splenic dendritic cells. These properties of liver dendritic cells contribute to their unique role in the induction of tolerance.

Increased expression of Toll like receptor 4 on peripheral-blood mononuclear cells in patients with coronary arteriosclerosis disease.

The family of Toll-like receptors (TLRs) initiates innate immune responses, and Toll-like receptor 4 (TLR4) was considered to be an important player in the initiation and progression of atherosclerotic disease. The aim of the study was to investigate the expression of TLR4 on peripheral-blood mononuclear cells (PBMCs) in patients with coronary arteriosclerosis disease (CAD). We have examined the expression of TLR4 protein and mRNA by flow cytometry (FCM) and real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). In addition, the levels of plasma lipids were determined by automatic biochemistry analyzer. The results showed that the positive rates and the mean mRNA copy number of TLR4 in CAD group were significantly higher than that in controls. But no significant difference was found in the positive rate and the mean mRNA copy number of TLR4 between CAD group with normal level of plasma lipids and the CAD group with abnormal level of plasma lipids. We suggest that expression level of TLR4 on peripheral-blood mononuclear cells is increased in atherosclerotic, but the differential expression of TLR4 has no correlation with the level of plasma lipids.