Role of intestinal flora in the development of nonalcoholic fatty liver disease in children.

In China, 45% of adolescents with obesity develop fatty liver disease, a condition that increases the long-term risk of developing cirrhosis and liver cancer. Although the factors triggering nonalcoholic fatty liver disease (NAFLD) vary in children, the composition of intestinal microflora has been found to play an increasingly important role. However, evidence is limited on the prevalence of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) in Chinese children. Therefore, this study aimed to evaluate the fecal microbiome of Chinese children with NAFLD and further analyze the potential of flora in regulating NAFLD-related symptoms and metabolic functions. Specifically, the study applied a 16S rRNA and metagenomic sequencing to the fecal samples of pediatric patients with NAFLD, NASH, and NAFL, as well as healthy controls, to explore the correlation among NAFLD-related indexes, metabolic pathways, and gut flora. The findings showed that some fecal microbiota had a negative correlation with body mass index, and various NAFLD-related bacteria, including Lachnoclostridium, Escherichia-Shigella, and Faecalibacterium prausnitzii, were detected. Consequently, the study concluded that the variation in gut microbiota might be more important in improving NAFLD/NASH compared with single species, providing a microbiota diagnostic profile of NAFLD/NASH.IMPORTANCEThis study aims to characterize the gut microbiota in Chinese children with nonalcoholic fatty liver disease (NAFLD) through 16S rRNA and metagenomic sequencing. The results highlight the association between fecal microbiota and NAFLD in Chinese children, demonstrating distinct characteristics compared to adults and children from other countries. Based on the sequencing data from our cohort's fecal samples, we propose a microbiota model with a high area under the curve for distinguishing between NAFLD and healthy individuals. Furthermore, our follow-up study reveals that changes in the relative abundance of microbial biomarkers in this model are consistent with variations in patients' body mass index. These findings suggest the potential utility of the microbiota model and microbial biomarkers for diagnosing and treating NAFLD in children.

Analysis of the gut microbiota in children with gastroesophageal reflux disease using metagenomics and metabolomics.

Background: There is no direct evidence of gut microbiota disturbance in children with gastroesophageal reflux disease (GERD). This study aimed to provide direct evidence and a comprehensive understanding of gut microbiota disturbance in children with GERD through combined metagenomic and metabolomic analysis. Methods: 30 children with GERD and 30 healthy controls (HCs) were continuously enrolled, and the demographic and clinical characteristics of the subjects were collected. First, 16S rRNA sequencing was used to evaluate differences in the gut microbiota between children with GERD and HC group, and 10 children with GERD and 10 children in the HC group were selected for metagenomic analysis. Nontargeted metabolomic analysis was performed using liquid chromatography/mass spectrometry (LC/MS), and metagenomic and metabolomic data were analyzed together. Results: There were significant differences in the gut microbiota diversity and composition between children with GERD and HCs. The dominant bacteria in children with GERD were Proteobacteria and Bacteroidota. At the species level, the top three core bacterial groups were Bacteroides stercoris, Bacteroides vulgatus and Alistipes putredinis. The main differential pathways were identified to be related to energy, amino acid, vitamin, carbohydrate and lipid metabolism. LC/MS detected 288 different metabolites in the positive and negative ion modes between children with GERD and HCs, which were mainly involved in arachidonic acid (AA), tyrosine, glutathione and caffeine metabolism. Conclusion: This study provides new evidence of the pathogenesis of GERD. There are significant differences in the gut microbiota, metabolites and metabolic pathways between HCs and children with GERD, and the differences in metabolites are related to specific changes in bacterial abundance. In the future, GERD may be treated by targeting specific bacteria related to AA metabolism.

Analysis of the correlation between P27 expression and Helicobacter pylori infection in gastric cancer.

We aimed to explore the correlation between P27 expression and Helicobacter pylori (H. pylori) infection in gastric cancer, so as to provide evidence for understanding the pathogenesis of gastric cancer caused by H. pylori infection. A total of 82 samples of gastric cancer tissues and 56 samples of tumor-adjacent normal tissues collected from the gastrectomy were enrolled in this study. Then, 14C-urease breathing test was carried out to evaluate the infection of H. pylori in gastric cancer tissues, the expression of P27 in the tissue samples was detected by the immunohistochemistry staining, and the correlation between the H. pylori infection and P27 expression in gastric cancer was analyzed. Of 82 gastric cancer patients, there were 53 patients with H. pylori infection (64.63%). Among the patients with highly or moderately differentiated gastric cancer, the expression of P27 was much higher than that of patients with poorly differentiated gastric cancer (p < 0.01). Besides, comparison of the P27 expression between males and females, among different age groups, tumor sizes, TNM stages, tumor infiltration degrees, or lymph node metastasis, showed no significant differences (p > 0.05). Analysis of the correlation revealed that P27 expression was negatively correlated with the infection of H. pylori (p < 0.01). Multifactorial logistics regression analysis indicated that tumor differentiation was a risk factor of P27-positive expression in gastric cancer tissues (p < 0.01). In addition, P27 expression in the gastric cancer tissues was lower than that in the tumor-adjacent normal tissues (p < 0.01). In gastric cancer patients, expression of P27 is correlated with H. pylori infection which, via downregulating P27, can cause the cancerization of gastric mucosa, and P27, for its role in the development and progression of gastric cancer, is a potential auxiliary indicator for clinical diagnosis whether gastric cancer is complicated with H. pylori infection. So, P27 is a key indicator for diagnosis, treatment, and prognostic evaluation of disease in the advanced stage.

Stock price forecasting based on Hausdorff fractional grey model with convolution and neural network.

Forecast of stock prices can guide investors' investment decisions. Due to the high-dimensional and long-memory characteristics of stock data, it is difficult to predict. The fractional grey model with convolution (FGMC (1, m)) can be used to predict time series, because of its memory and ability to process high-dimensional data. However, the FGMC (1, m) model has some disadvantages, including complex calculation, loss of information, and approximate background values. In this paper, Hausdorff fractional derivative and Newton-Cotes formula are used to optimize these shortcomings and can get a Hausdorff fractional grey model with convolution (HFGMC (1, m)) model. The HFGMC (1, m)-LLE-BP model is proposed in this paper. HFGMC (1, m) provides a solution that can reduce the complexity of the cumulative generator matrix calculation and preserve the global information of the sequence. Newton-Cotes formula is used to calculate the background value, which can solve the shortcomings of approximate background values. The HFGMC (1, m) model is used to predict the linear component of the sequence, and the BP neural network is used to predict the nonlinear component of the sequence. In addition, because of the high-dimensional and nonlinear characteristics of stock data, a local linear embedding (LLE) algorithm is used to remove redundant information in high-dimensional non-linear data. The experimental results show that the HFGMC (1, m)-LLE-BP model is effective for predicting the stock price in different trends.

Distribution and risk factor analysis for Clostridium difficile-associated diarrhea among hospitalized children over one year of age.

IMPORTANCE: Clostridium difficile-associated diarrhea (CDAD) is a severe type of antibiotic-associated diarrhea (AAD). However, the risk factors for CDAD in children with AAD have not yet been clarified. OBJECTIVE: To investigate the distribution and risk factors for CDAD among hospitalized children in Beijing Children's Hospital. METHODS: Stool samples from 197 children with AAD were tested for the C. difficile pathogenic genes (tcdA, tcdB, tcdC, tcdD, tcdE, cdtA, and cdtB) using polymerase chain reaction between January 2011 and January 2014. Children who tested positive for tcdA or tcdB were included in the CDAD group, and those remaining comprised the non-CDAD group. RESULTS: The rate of CDAD among the 197 children with AAD was 42.6% (84/197). The age distribution was 1-15.6 years, among which the majority of children (54.8%, 46/84) were aged 1-4 years. Differences in the CDAD-positive rates among AAD children belonging to different age groups were not statistically significant. Univariate analysis revealed that the duration of antibiotic therapy, the length of hospitalization prior to diarrhea, and gastrointestinal tract operations were significant risk factors (P < 0.05). Children with CDAD underwent more antibiotic therapy and had longer periods of hospitalization prior to diarrhea onset than children in the non-CDAD group. Using multivariate regression analysis, hospitalization for ≥ 10 days prior to diarrhea was found to be an independent risk factor for CDAD. INTERPRETATION: This study revealed that the length of hospitalization (≥ 10 days) prior to diarrhea was an independent risk factor for CDAD in children with AAD.

An Observational Study on Aberrant Methylation of Runx3 With the Prognosis in Chronic Atrophic Gastritis Patients.

The aim of this study is to discuss whether the methylation levels of Runx3 could be used as the early biomarker for predicting the prognosis in chronic atrophic gastritis (CAG) patients. A total of 200 subjects including 60 controls without CAG (Group 1), 70 patients with mild CAG (Group 2), and 70 patients with moderate and severe CAG (Group 3) were recruited for this cross-sectional investigation in the Department of Gastroenterology in Daqing Oilfield General Hospital from July 2013 to May 2014. The MlALDI-TOF-MS was used to measure the methylation levels of Runx3 in all of the subjects. Real-time quantitative reverse transcription polymerase chain reaction and western blotting were chosen to determine the expression levels of Runx3. The correlations between methylation levels of Runx3 among these CAG patients and their prognosis were shown by logistic regression models. The results demonstrated that the methylation levels of CpG13, CpG14, and CpG15 in Runx3 were higher in Group 3 than those in Groups 1 and 2 (P <0.05), whereas the mRNA and protein expression levels of Runx3 were lower in Group 3 than those in Groups 1 and 2 (P <0.05). There were significantly negative correlations between the methylation levels of Runx3 with its expression and the healing prognosis of CAG patients. In brief, this study proved that the hypermethylation modifications of CpG13, CpG14, and CpG15 in the promoter region of Runx3 could result in the down regulation of Runx3 expression to affect the prognosis of CAG. So the methylation levels of these CpG sites in Runx3 in the peripheral blood can be used as the biomarker for predicting the healing prognosis of CAG patients.

Corticosteroid Therapy Might be Associated with the Development of Coronary Aneurysm in Children with Kawasaki Disease.

BACKGROUND: Coronary artery lesions (CALs) are known to be the main complication in children with Kawasaki disease (KD). Instead of intravenous immunoglobulin (IVIG), corticosteroid therapy has been accepted to be used for children with KD who are unresponsive to IVIG. This study aimed to evaluate risk factors for CALs in children with KD. METHODS: We retrospectively reviewed the clinical records of 2331 children with KD from January 2005 to December 2014. To identify the independent risk factors for CALs, multivariable logistic regression models were constructed using significant variables identified from univariate logistic regression analysis. RESULTS: The incidence of CALs was 36.0% (840 of 2331), including 625 (26.8%) coronary artery dilations and 215 (9.2%) coronary artery aneurysms (CAAs). Multivariable logistic regression analysis identified that male, incomplete KD, longer fever duration, and C-reactive protein (CRP) >100 mg/L were independent risk factors for coronary artery dilatations. On the other hand, male, incomplete KD, longer fever duration, prolonged days of illness at the initial treatment, corticosteroid therapy, sodium ≤133 mmol/L, and albumin <35 g/L were the independent risk factors for CAAs. In addition, corticosteroid therapy, prolonged days of illness at the initial treatment, and albumin <35 g/L were the independent risk factors for giant CAAs. CONCLUSIONS: CALs might be associated with male sex, incomplete KD, longer fever duration, prolonged days of illness at the initial treatment, albumin <35 g/L, sodium ≤133 mmol/L, CRP >100 mg/L, and corticosteroid therapy. Corticosteroid therapy was an independent risk factor for CAAs and giant CAAs. Thus, corticosteroids should be used with caution in the treatment of KD with the risk for CALs.

Formal modeling and verification of fractional order linear systems.

This paper presents a formalization of a fractional order linear system in a higher-order logic (HOL) theorem proving system. Based on the formalization of the Grünwald-Letnikov (GL) definition, we formally specify and verify the linear and superposition properties of fractional order systems. The proof provides a rigor and solid underpinnings for verifying concrete fractional order linear control systems. Our implementation in HOL demonstrates the effectiveness of our approach in practical applications.

[Virulence genes and clinical features of Clostridium difficile-associated diarrhea in children].

OBJECTIVE: Clostridium difficile is an obligate anaerobic Gram-positive bacillus, it can cause Clostridium difficile-associated diarrhea (CDAD). This study aimed to investigate the virulence genes and clinical features of CDAD in children by gene detection. METHOD: From May 2012 to January 2013, the 121 inpatients in Beijing Children's Hospital who suffered from diarrhea after antibiotics treatment were detected for Clostridium difficile virulence genes including the five genes for pathogenic loci (tcdA, tcdB, tcdC, tcdD, tcdE) and the genes for binary toxin CDT (cdtA and cdtB) using polymerase chain reaction (PCR) in order to research the clinical features of CDAD, and analyze target products by sequencing. RESULTS: In the 121 children with diarrhea, 60 (49.6%) were toxin B-positive,including 12 toxin A-positive and toxin B-positive (A+B+), 48 toxin A-negative but toxin B-positive (A-B+). The toxin A-positive but toxin B-negative (A+B-) specimens or binary toxin (cdtA and cdtB)-positive specimens were not detected. Of 60 tcdB-positive specimens, tcdC, tcdD and tcdE positive specimens were 24 (40%), 25 (42%), 24 (40%), respectively. The sequencing results of tcdA, tcdB, tcdC, tcdD, and tcdE gene were consistent with the reference sequence. In the 60 children with CDAD, infants (≤3 years) accounted for 62% (37/60). The duration of diarrhea was 3-77 days, and 42 (70%) cases had acute diarrhea; 39 (65%) patients had fever, 40 (67%) had anemia, 36 (60%) had abnormal white blood cell count, 30 (50%) had hypoalbuminemia, 25 (42%) had elevated C-reactive protein (CRP). The level of CRP in positive group was significantly higher compared to the negative group (45.0(16.0,89.0) mg/L vs. 19.0(14.5,41.5) mg/L, Z=-2.008, P=0.045). The level of plasma albumin in positive group was significantly lower compared to the negative group (35.3(29.7,39.8) g/L vs. 38.5(33.9,41.5) g/L, Z=-2.610, P=0.009). There were no significant differences in gender, age, duration of diarrhea, hospital staytime, time of using antibiotics and laboratory test between A+B+ group and A-B+ group (all P>0.05). CONCLUSION: The main virulence genotype of Clostridium difficile was toxin A-negative but toxin B-positive in this research. The clinical features of CDAD in children were acute diarrhea with fever. Laboratory examination showed that white blood cell count was abnormal, CRP was increased, hemoglobin and plasma albumin were reduced.

Effects of gene silencing of CypB on gastric cancer cells.

OBJECTIVE: To determine the effect of gene silencing of cyclophilin B (CypB) on growth and proliferation of gastric cancer cells. METHODS: CypB siRNA lentivirus (LV-CypB-si) and control lentivirus (LV-si-con) were produced. CypB expression in gastric cancer cell lines was detected by Western blot. BGC823 and SGC7901 cells were chosen to be infected with LV-si-con and LV-CypB-si, and stable transfectants were isolated. The cell groups transfected with LV-CypB-siRNA, LV-siRNA-con and transfected no carrier were served as the experimental group, the implicit control group and the blank control group respectively. MTT and colony formation assays were used to examine the effect of CypB on the cell growth and proliferation in vitro. Cell cycle was analyzed with flow cytometry. The expression of VEGFR of BGC823-si and SGC7901-si was detected by Western blot. RESULTS: Gene silencing of CypB can inhibit gastric cancer cell growth, proliferation, cell cycle progress and tumorigenesis. CypB expression level was obviously higher in SGC7901 and BGC823 than MKN28 and GES. These two cell lines were infected with LV-si-con and LV-CypB-si respectively. MTT and cloney formation assays showed a significantly decreased rate of cell proliferation from the forth day or the fifth day in cells transfected with LV-CypB-si (P<0.05). Down-regulation of CypB resulted in slightly decreased percentage of S phase and increased percentage of G1 (P<0.05). These findings indicated that CypB could promote the G1-S transition of gastric cancer cell. In addition, the expression of VEGF of BGC823 and SGC7901 transfected with CypB siRNA was reduced in comparison with the implicit control group and the blank control group. CONCLUSIONS: Gene silencing of CypB decreases gastric cancer cells proliferation and in vivo tumorigenesis. These findings indiccate CypB could be a potential biomarker and therapeutic target for gastric cancer.

Effects and mechanism of miR-214 on hepatocellular carcinoma.

OBJECTIVE: To explore the role of miR-214 in the progression of hepatocellular carcinoma (HCC) and its inhibitory mechanisms in depressing the signaling pathway of ß-catenin, this study was conducted. METHODS: We ectopically expressed miR-214 in HepG2 cells to obtain cell lines Lv-miR-214-HepG2 and their control Lv-control-HepG2. Differences between the two cell lines were compared in cell growth, proliferation, colony forming ability and cell cycles. RT-PCR method was applied for the quantification of ß-catenin mRNA expression. Western-blot method was applied for the determination of the protein level of ß-catenin and their downstream targets (ie. Cyclin D1, c-Myc and TCF-1). The effect of miR-214 on cells was further explored through RNA interference and restoring miR-214 expression. RESULTS: In comparison with negative (Lv-control-HepG2) and blank (HepG2) control, a significant inhibition of cell growth and proliferation caused by miR-214 was observed after 48∼72h of cell culture experiments (P<0.05). The miR-214 treatment resulted in a colony forming efficiency of (23.28±3.26)%, which was significantly lower than that of negative control [(51.31±3.97)%] (P<0.05). According to FCM results, the experimental group, compared with control, showed a higher proportion of cells in G0/G1 phase [(70.32±3.12)%] but a lower proportion in S phase [(18.42±2.90)%] (P<0.05). The MTT assay demonstrated a significant inhibition of the proliferation and ß-catenin expression of HCC cells compared with control (P<0.05), while no significant difference was observed after HCC cells being transfected with ß-catenin overexpression plasmid (P>0.05). By comparing to the RT-PCR and Western-blot results of control, the miR-214 treatment led to a slightly decrease in the ß-catenin mRNA expression (P>0.05), but an extremely inhibition in the protein level of ß-catenin and its downstream targets Cyclin D1, c-Myc, and TCF-1 (P<0.05). CONCLUSIONS: miR-214 functions as a suppressor during the progression of HCC, and its inhibitory role was achieved by down-regulating ß-catenin signaling pathway.

Impacts of infection with different toxigenic Clostridium difficile strains on faecal microbiota in children.

Increasing evidence suggests that altered intestinal microbial composition and function result in an increased risk of Clostridium difficile-associated diarrhoea (CDAD); however, the specific changes of intestinal microbiota in children suffering from CDAD and their associations with C. difficile strain toxigenicity are poorly understood. High-throughput pyrosequencing showed that reduced faecal bacterial diversity and dramatic shifts of microbial composition were found in children with CDAD. The Firmicutes/Bacteroidetes ratio was increased significantly in patients with CDAD, which indicated that dysbiosis of faecal microbiota was closely associated with CDAD. C. difficile infection resulted in an increase in lactate-producing phylotypes, with a corresponding decrease in butyrate-producing bacteria. The decrease in butyrate and lactate buildup impaired intestinal colonisation resistance, which increased the susceptibility to C. difficile colonisation. Strains of C. difficile which were positive for both toxin A and toxin B reduced faecal bacterial diversity to a greater degree than strains that were only toxin B-positive, and were associated with unusually abundant Enterococcus, which implies that the C. difficile toxins have different impacts on the faecal microbiota of children. Greater understanding of the relationships between disruption of the normal faecal microbiota and colonisation with C. difficile that produces different toxins might lead to improved treatment.