Effect of dietary concentrate level on digestibility of nutrients in each region of the gastrointestinal tract and rumen fermentation in goats.

This study evaluated the effects of high concentrate diets (HCD) on the rumen fermentation and the digestibility of nutrients in different sites of the gastrointestinal tract (GIT) in goats. Four goats were used in a crossover design. The goats were fitted with a ruminal cannula and flexible T-cannulae proximal duodenum and terminal ileum. Treatments were as follows: low concentrate group (LCG) and high concentrate group (HCG). Duodenal flow and forestomach digestibility of starch were significantly higher in the HCG than those in the LCG (p < 0.05); There was no significant difference in ileum flow and digestibility of starch in the small intestine, large intestine and total GIT (p > 0.05). The digestibility of crude protein (CP) in the forestomach was significantly higher in the HCG than in the LCG (p < 0.05); the flow of the duodenum and ileum of CP, and the CP digestibility of the small intestine, large intestine and total GIT were not significantly different between groups (p > 0.05). The duodenal and ileal flow of neutral detergent fiber (NDF), the NDF digestibility of the different segments and total GIT were not significantly different between groups (p > 0.05). Compared to the LCG, the ruminal pH of the HCG was significantly lower (p < 0.05). The HCG concentrations of microbial crude protein, ammonia nitrogen and isovaleric acid were significantly higher (p < 0.05) than the LCG. The foam strength, foam production and viscosity of the rumen fluid in the HCG were higher than the LCG (p < 0.01). These results showed that when the goats were fed with HCD, the digestibility of nutrients was not significantly impaired, but the risk of frothy rumen bloat increased. ImplicationsDue to a serious shortage of high-quality roughage in China, producers commonly used a high-concentrate diet in ruminants, which can improve animal production performance.Gastrointestinal digestive function plays a vital role in the absorption of nutrients and the healthy growth of animals.Therefore, this research evaluated the digestibility of various nutrients in different segments of the gastrointestinal tract (GIT) under HCD feeding by using three-site cannula goats as experimental animals.The results indicated that the GIT of goats could fully digest nutrients such as starch and protein under HCD feeding conditions.

Artificial selection on storage protein 1 possibly contributes to increase of hatchability during silkworm domestication.

Like other domesticates, the efficient utilization of nitrogen resources is also important for the only fully domesticated insect, the silkworm. Deciphering the way in which artificial selection acts on the silkworm genome to improve the utilization of nitrogen resources and to advance human-favored domestication traits, will provide clues from a unique insect model for understanding the general rules of Darwin's evolutionary theory on domestication. Storage proteins (SPs), which belong to a hemocyanin superfamily, basically serve as a source of amino acids and nitrogen during metamorphosis and reproduction in insects. In this study, through blast searching on the silkworm genome and further screening of the artificial selection signature on silkworm SPs, we discovered a candidate domestication gene, i.e., the methionine-rich storage protein 1 (SP1), which is clearly divergent from other storage proteins and exhibits increased expression in the ova of domestic silkworms. Knockout of SP1 via the CRISPR/Cas9 technique resulted in a dramatic decrease in egg hatchability, without obvious impact on egg production, which was similar to the effect in the wild silkworm compared with the domestic type. Larval development and metamorphosis were not affected by SP1 knockout. Comprehensive ova comparative transcriptomes indicated significant higher expression of genes encoding vitellogenin, chorions, and structural components in the extracellular matrix (ECM)-interaction pathway, enzymes in folate biosynthesis, and notably hormone synthesis in the domestic silkworm, compared to both the SP1 mutant and the wild silkworm. Moreover, compared with the wild silkworms, the domestic one also showed generally up-regulated expression of genes enriched in the structural constituent of ribosome and amide, as well as peptide biosynthesis. This study exemplified a novel case in which artificial selection could act directly on nitrogen resource proteins, further affecting egg nutrients and eggshell formation possibly through a hormone signaling mediated regulatory network and the activation of ribosomes, resulting in improved biosynthesis and increased hatchability during domestication. These findings shed new light on both the understanding of artificial selection and silkworm breeding from the perspective of nitrogen and amino acid resources.

Ultrasensitive detection of UO2 2+ based on dopamine-functionalized MoOx quantum dots.

Uranium is an important nuclear fuel and the risk of human exposure to uranium increases as increasing amounts of uranium-containing waste enter the environment due to the rapid growth of nuclear power. Therefore, rapid, sensitive, and portable uranium detection is a promising approach to effectively control and monitor uranium contamination. To achieve this goal, abundant oxygen- and nitrogen-containing groups were introduced to molybdenum oxide quantum dot (MoOx QDs) surfaces with dopamine (DA) modification. Due to the excellent coordination ability of oxygen- and nitrogen-containing groups with uranium, the obtained DA-functionalized MoOx QDs (DA-MoOx QDs) showed a strong binding affinity for uranium and sensitivity was increased nearly 1000-fold compared with MoOx QDs alone. The limit of detection was 3.85 nM, which is higher than most of the reported nanomaterials. Moreover, the DA-MoOx QD-based method showed high selectivity and uranium could be clearly detected under masking with ethylenediaminetetraacetic acid even when the concentration of other metal ions was 100-fold higher than that of uranium, showing a very promising method for uranium contamination control and monitoring.

Rapid and sensitive detection of Mycobacterium tuberculosis based on strand displacement amplification and magnetic beads.

Tuberculosis is one of the main infectious diseases threatening public health, and the development of simple, rapid, and cost-saving methods for tuberculosis diagnosis is of profound importance for tuberculosis prevention and treatment. The bacterium Mycobacterium tuberculosis (MTB) is the pathogen that causes tuberculosis, and assaying for MTB is the only criterion for tuberculosis diagnosis. A new enzyme-free method based on strand displacement amplification and magnetic beads was developed for simple, rapid, and cost-saving MTB detection. Under optimum conditions, a good linear relationship could be observed between fluorescence and MTB specific DNA concentration ranging from 0.05 to 150 nM with a correlation coefficient of 0.993 (n = 8) and a detection limit of 47 pM (3σ/K). The present method also distinguished a one base mismatch from MTB specific DNA, showing great promise for MTB genome single base polymorphism analysis. MTB specific DNA content in polymerase chain reaction samples was successfully detected using the new method, and recoveries were 97.8-100.8%, indicating that the present method had high accuracy and shows good potential for the early diagnosis of tuberculosis.

Quasi-classical trajectory study of the N(2D) + H2(X1ΣG+) → NH(X3Σ-) + H(2S) reaction based on an analytical potential energy surface.

Using the multireference configuration interaction method with the Davidson correction and a large orbital basis set (aug-cc-pV5Z), we obtain an energy grid that includes 17,500 points for the construction of a new analytical potential energy surface (APES) for the N((2)D) + H(2)(X(1)Σ(g)(+)) → NH(X(3)Σ(-)) + H((2)S) reaction. The APES, which contains 145 parameters and is represented with a many-body expansion and a new switch function, is fitted from the ab initio energies using an adaptive nonlinear least-squares algorithm. The geometric characteristics of the reported APES in the literature and those of our APES are also compared. On the basis of the APES that we obtained, reaction cross sections are computed by means of quasi-classical trajectory calculations and compared with the experimental and theoretical values available in the literature.

A new analytical potential energy surface for the singlet state of He2H+.

The analytic potential energy surface (APES) for the exchange reaction of HeH(+) (X(1)Σ(+)) + He at the lowest singlet state 1(1)A(∕) has been built. The APES is expressed as Aguado-Paniagua function based on the many-body expansion. Using the adaptive non-linear least-squares algorithm, the APES is fitted from 15 682 ab initio energy points calculated with the multireference configuration interaction calculation with a large d-aug-cc-pV5Z basis set. To testify the new APES, we calculate the integral cross sections for He + H(+)He (v = 0, 1, 2, j = 0) → HeH(+) + He by means of quasi-classical trajectory and compare them with the previous result in literature.

[A multicenter study of coronary artery disease and its risk factors in rheumatoid arthritis in China].

OBJECTIVE: To learn about the prevalence and risk factors of coronary artery disease (CAD) in rheumatoid arthritis (RA). METHODS: Data were obtained from a 12-month retrospective investigation of the patients with RA, randomly selected from Departments of Rheumatology and Immunology in 21 big hospitals in China. The data were collected about their social conditions, clinical conditions, medications associated with RA, such as disease modifying anti-rheumatic drugs (DMARDs), non steroidal anti-inflammatory drugs (NSAIDs), glucocorticoid, biologic agents. A nonparameter test and multivariate logistic regression analysis were performed. RESULTS: In the study, 960 patients were enrolled. The prevalence of CAD was 3.5% in China, which was obviously higher than that of normal people. The prevalence of overweight and obesity, smoking, hypertension, diabetes mellitus, hypercholesterolemia and cerebrovascular disease were 35.1%, 12.3%, 17.0%, 7.7%, 0.4% and 3.0%, respectively. Compared with the control group, the CAD group had higher age [(64.7±9.3) years vs. (52.3±14.0) years,P<0.001], more rheumatoid nodules (14.7% vs. 3.1%,P=0.005), lower rate of hydroxychloroquine (HCQ) use (5.9% vs. 22.6%,P=0.021), higher prevalence rates of lung interstitial disease (17.5% vs. 7.0%,P<0.001), diabetes mellitus and hypertension (29.4% vs. 7.0%,P<0.001; 38.2% vs. 16.2%,P=0.001). There was no obvious correlation of CAD in RA with joint deformity, rheumatoid factor (RF) titer, glucocorticoid use, hypercholesterolemia and body mass index (BMI). Multivariate analysis showed higher age, diabetes mellitus and hypertension were independent predictors of CAD, and the use of HCQ was a protective factor of CAD. CONCLUSION: The prevalence of CAD is 3.5%. Higher age, diabetes mellitus and hypertension are independent predictors of CAD, and the use of HCQ is a protective factor of CAD.

[Survey of tumor necrosis factor inhibitors application in patients with rheumatoid arthritis in China].

OBJECTIVE: To investigate the current status of tumor necrosis factor (TNF) inhibitors application in rheumatoid arthritis (RA) patients in China and to analyze the related factors. METHODS: A retrospective survey was conducted in 21 hospitals from different parts of China. The patients with RA were randomly enrolled. Data of their social backgrounds, clinical conditions, usage and adverse effects of TNF inhibitors were collected. The costs of TNF inhibitors and the indirect costs of the disease were calculated. A multivariate Logistic regression analysis was performed to analyze the factors related to TNF inhibitors application. RESULTS: In the study, 1 095 RA patients from July 2009 to November 2010 were enrolled, of whom 112 had received TNF inhibitors, representing 10.2% of the total patients. The patients who received etanercept and infliximab were 7.4% (86/1 095) of the patients and 2.4% (26/1 095), respectively. There were 0.5% of the patients (5/1 095) who had received both of the TNF inhibitors. The patients who had accepted etanercept and treatment duration for less than 3 months and 3-6 months accounted for 38.5% and 25.0% respectively, while those treated with Infliximab were 38.1%. Their health assessment questionnaire (HAQ) scores were 1.1, 0.5 and 0.1, corresponding to treatment duration of infliximab for less than 3, 3-6 and 6-9 months and those were 1.3, 1.0, 0.3 corresponding to treatment duration of etanercept, respectively. Infliximab costs were RMB 24 525.0, 69 300.0 and 96 800.0 Yuan and etanercept costs were RMB 7 394.8, 9 158.6, 54 910.9 Yuan, respectively. Indirect costs for RA patients who accepted infliximab for less than 3, 3-6 and 6-9 months were RMB 365.6, 0 and 158.9 Yuan and those who accepted etanercept were RMB 2 158.4, 288.5 and 180.1 Yuan, respectively. Allergy and infection were the main side-effects of etanercept and both happened in 3.5% of all the patients. Liver damage happened in 2.3% of all the patients, while allergy and infection happened in 6.5% of all the patients who accepted infliximab. Logistic regression analysis showed that patients with higher education experience increased the odds of entering the TNF inhibitors group (OR: 1.292, 95%CI: 1.132-1.473, P=0.000). CONCLUSION: About one-tenth of RA patients in China have accepted TNF inhibitors. Higher education experience is the key factor for using TNF inhibitors.

[Sulphasalazine in patients with rheumatoid arthritis in China: a cross-sectional study].

OBJECTIVE: To investigate the medication status of rheumatoid arthritis (RA) patients and to analyze the clinical use of sulphasalazine (SSZ) and the adverse effect. METHODS: A total of 1 096 outpatients and inpatients diagnosed with RA were investigated in 21 hospitals all over China from July 2009 to December 2010, including gender, age of onset, clinical manifestations, as well as the clinical characteristics and medication status of 160 RA patients who received SSZ therapy. RESULTS: In the group of 160 patients who received SSZ, the male-to-female ratio was 1:7, The average age at onset was (46.1±15.0) years, while the average course was (9.9±7.8) years. The average dose of sulphasalazine was (1.87±0.52) g/d for a mean duration of (26.3± 14.6) months. Only 17% (27/160) of the patients received SSZ monotherapy. Methotrexate (63.1%), leflunomide (36.2%) and hydroxychloroquine (18.1%) were most commonly used combination drugs. And 36.2% (58/160) of the patients used the two-drug combination of methotrexate plus sulphasalazine .In this group, 41.9% (67/160) once used SSZ but withdrew for adverse events and other reasons, while 17.5% (28/160) withdrew for adverse events, of which the most common were gastrointestinal (8.8%), skin (3.8%) and liver toxicity (3.1%). CONCLUSION: Sulphaszlazine is not a common choice in the RA therapeutics in China, and the average dose of SSZ is lower than the standard dose of 2 to 3 g/d . The adverse events of SSZ are common; however, there are few severe adverse events or threat to life,SSZ is relatively safe in clinical practice.

6-[4-(Diphenyl-amino)-phen-yl]quinoline 1-oxide.

In the title mol-ecule, C(27)H(20)N(2)O, a triphenyl-amine derivative of quinoline, the three benzene rings linked through an N atom form a propeller shape, with dihedral angles between the mean planes of pairs of rings of 75.57 (9), 55.68 (9) and 83.66 (9)°. The quinoline ring is essentially planar, with an r.m.s. deviation of the fitted atoms of 0.0155 Å, and forms a dihedral angle of 33.52 (8)° with the benzene ring to which it is bonded. Weak C-H⋯π inter-actions are also observed in the crystal structure.

Beware of the DeBakey type I aortic dissection hidden by ischemic stroke: Two case reports.

BACKGROUND: DeBakey type I aortic dissection is one of the rare etiologies of ischemic stroke. It is critical to identify arterial dissection before intravenous thrombolysis; otherwise, fatal hemorrhage may occur. CASE SUMMARY: In this report, we described 2 painless DeBakey type I aortic dissection cases with initial symptoms similar to ischemic stroke. Sudden onset of conscious disturbance and limb weakness within minutes occurred in both cases. Hypotension was found in both cases. Thoracoabdominal computed tomography angiography was urgently performed due to unknown reason hypotension, and DeBakey type I aortic dissection was confirmed. Intravenous thrombolysis was avoided because of timely diagnosis; however, they both eventually died of ruptured aortic dissection. CONCLUSION: Aortic dissection should always be excluded in ischemic stroke patients with unexplained hypotension or shock symptoms before intravenous thrombolytic therapy.

Isolation and characterization of two new chroman-4-ones from the endophytic fungus Penicillium chrysogenum obtained from Eucommia ulmoides Oliver.

Two new chroman-4-ones penicichromanone A (1) and penicichromanone B (2), together with three known compounds conioxepinol C (3), emodin (4) and moniliphenone (5), were obtained from the endophytic fungus Penicillium chrysogenum, which was isolated from the bark of Eucommia ulmoides Oliver. The structures of 1 and 2 were elucidated by detailed analysis of HRESIMS, 1D/2D NMR and ECD spectra. All the compounds were evaluated for their anti-inflammatory activities using HEK293 cells, and compounds 1, 3, 4 and 5 exhibited significant inhibitory effects on TNF-α-stimulated NF-κB activation.

[Expression and significance of phosphatidylinositol 3-kinase/protein kinase B signal transduction pathway in severe acute pancreatitis-associated lung injury].

OBJECTIVE: To investigate the expression and significance of phosphatidylinositol 3-kinase/protein kinase B (PI3K/PKB) signal transduction pathway in severe acute pancreatitis-associated lung injury. METHODS: Twenty-four healthy male Changbai pigs were randomized into four groups: sham operation group (n = 6), ALI group (n = 6), ALI plus LPS (lipopolysaccharide) group (n = 6) and ALI plus Wortmannin group (n = 6). The expression levels of PI3K and PKB were determined by both RT-PCR and Western blot. Activity changes of NF-kappaB were detected by electrophoretic mobility shift assay (EMSA). Contents of TNF-alpha and IL-1beta in bronchoalveolar lavage fluid (BALF) were examined by ELISA. The histopathological changes of lung were observed. RESULTS: The expressions of mRNA and protein PI3K and PKB, NF-kappaB activity and TNF-alpha, IL-1beta in BALF in ALI group were higher than those in sham operation group (P < 0.05 or P < 0.01). In ALI plus LPS group, they increased significantly in comparison with ALI group and sham operation group after injection of LPS (P < 0.05 or P < 0.01). In ALI plus Wortmannin group, these parameters were significantly inhibited by Wortmannin in comparisons with ALI group and ALI plus LPS group (P < 0.05 or P < 0.01). CONCLUSION: The phosphatidylinositol 3-kinase/protein kinase B signal transduction pathway is found to participate in the pathological process of severe acute pancreatitis-associated lung injury through the up-regulations of NF-kappaB activity, TNF-alpha and IL-1beta.

[Adaptation of Suaeda salsa to water/sediment conditions and nitrogen input in tidal flat wetlands in the Yellow River Delta, China]. / é»„æ²³ä¸‰è§’æ´²æ»¨å²¸æ½®æ»©æ¹¿åœ°ç¢±è“¬å¯¹æ°´æ²™æ¡ä»¶åŠæ°®è¾“å ¥çš„é€‚åº”æ€§.

The application of Water-Sediment Regulation Project provides abundant freshwater for the Yellow River Delta, changes water and sediment condition, as well as brings lots of exogenous substances. Using orthogonal test with three factors and four levels, we examined the effects of water condition, sediment burial depth and exogenous nitrogen input on the growth of wetland plant, Suaeda salsa. The results showed that sediment burial had great effect on protein content and SOD activity. Nitrogen input had great effect on POD activity. CAT activity was not affected by sediment burial, nitrogen input and water depth. The water depth manipulation had significant effect on leaf, stem and total dry weight. With the increases of water depth, leaf, stem and total dry weight showed a decreasing trend, with the maximum values (25.70, 40.86, 69.73 g) at the 2 cm water depth. There was no effect of nitrogen input and sediment burial on dry weight. The results of range analysis showed that the effect of water depth on leaf, stem, root and total dry weight was great, and followed by nitrogen input and sediment burial, with an optimal combination of 2 cm water depth +12 cm sediment burial + 9 g·m-2 nitrogen input. These findings suggested that water condition played a decisive role in affecting the growth of S. salsa. Consequently, more attention should be paid to the control of water depth in the process of water and sediment regulation.

The Oleaceae family: A source of secoiridoids with multiple biological activities.

In the quest to search and discover bioactive compounds from nature, terpenoids have emerged as one of the most interesting and researched classes of compounds. Secoiridoid, a type of the terpenoid, has also been extensively studied, especially their chemical structures and pharmacological effects. Oleaceae is a family of woody dicotyledonous plants with broad economic and medicinal values. This family contains a large number of flavonoids, monoterpenoids, iridoids, secoiridoids and phenylethyl alcohols, of which the secoiridoids have various biological activities. The purpose of this review is to summarize the phytochemical and pharmacological of the secoiridoids (glycosides, aglycones, derivatives and dimers) in the Oleaceae family from 1987 to 2018. This review will also serve as a reference for further studies.

Role of Aliphatic Chain Characteristics on the Anti-Cracking Properties of Polymer-Modified Asphalt at Low Temperatures.

The anti-cracking properties of polymer-modified asphalt depend largely on the molecular structure of the polymer modifier. However, the mysterious structure-performance relationship is still elusive. In this paper, three kinds of polymers with different chain structures were selected to address this issue. The indices of styrene, trans-butadiene, aliphatic branched-chain, and aliphatic long-chain from the infrared spectrum were used to quantify the functional group compositions of polymer modifiers. Viscoelastic parameters, including relaxation time, dissipation energy ratios, and stiffness were assessed to illustrate the anti-cracking properties of polymer-modified asphalt. Results showed that relaxation time and dissipation energy ratios were mainly determined by the polymer network strength, molecular size, aliphatic chain feature, and the orientations speed of aliphatic chains. The short relaxation time and high dissipation ratio lead to the low stiffness and favorable low-temperature performance of asphalt. The improvement of these performances requires a polymer with high indices of an aliphatic long-chain, styrene, aliphatic branched-chain, and trans-butadiene, respectively. An aliphatic-long chain, aliphatic branched-chain, and trans-butadiene were soft segments in asphalt while styrene was the rigid segment. The soft segments affect the intramolecular friction, orientation, and thermal motion at low temperatures, whereas the rigid segment enhances the strength of polymer networks. Thus, the anti-cracking property of polymer-modified asphalt can be improved by adjusting the ratio of soft and rigid segments in the polymer modifier.

[Effect of sFRP2 on the biological behavior of HepG2 cells].

OBJECTIVE: To investigate the effect of sFRP2 on the biological behavior of human hepatoma carcinoma HepG2 cells. METHODS: HepG2 cells were infected with recombinant adenovirus containing mouse sFRP2 gene, and then the proliferation, cell cycle distribution, expression of tumor metastasis related factors (CD44, CD82/KAI1, EMMPRIN) and beta-catenin protein, and migration ability of the cells were detected by MTT, FCM, immunohistochemistry, Western blot and Transwell inserts, respectively. RESULTS: sFRP2 protein inhibited the proliferation of HepG2 cells, and increased the percentage of G0/G1 period cells. Expression of CD44 and CD82/KAI1 proteins, which could inhibit invasion and metastasis of tumor cells, was upregulated. However, EMMPRIN protein, which could promote the above properties of tumor cells decreased in HepG2 cells infected with the recombinant adenovirus containing mouse sFRP-2 gene. Western blot demonstrated that beta-catenin was expressed in HepG2 cells and there was no significant difference between the treated and the control groups. Transwell insert test showed sFRP2 protein decreased the migration ability of HepG2 cells. CONCLUSION: The recombinant adenovirus containing mouse sFRP-2 gene could infect HepG2 cells. sFRP2 protein could significantly reduce the capability of proliferation, invasion and metastasis of HepG2 cells.

[Effects of Sediment Burial and Exogenous Cd Input on Biomass Allocation and Antioxidative Enzyme Activities of Suaeda salsa in the Coastal Wetland of the Yellow River Delta].

The Yellow River Delta has been facing the threat of functional degradation during the recent years. The Water-Sediment Regulation Project not only supplements abundant freshwater, but also alters the sediment burial and heavy metal levels, which affects vegetation growth. Thus, we selected the pioneer species Suaeda salsa, to study the effects of different sediment burial depths (0, 3, 6, 12 cm) and exogenous Cd inputs (0, 0.5, 1.0, 1.5 mg·kg-1) on biomass allocation and activities of antioxidative enzymes in the coastal wetlands of the Yellow River delta. The results showed that a shallow or moderate burial depth had a stimulatory effect on chlorophyll content, while an excessive burial depth inhibited the growth of Suaeda salsa and chlorophyll content. With increasing Cd input, chlorophyll content and dry mass decreased. At a lower Cd input and moderate burial depth, activities of CAT and SOD increased, and at high levels, SOD activities decreased, while activities of CAT at a 12 cm burial depth and 1.0 mg·kg-1, 1.5 mg·kg-1 Cd input were higher than those for the control (62.66% and 58.56%). CAT activities reached high values (15.76 U·mg-1) at a high Cd input (1.5 mg·kg-1) and burial depth (12 cm). Analysis of variance showed that Cd input had a significant effect on protein content, and CAT and SOD activities, and sediment burial depth had a significant effect on the protein content and SOD activities. Interaction between Cd input and sediment burial depth had a significant effect on CAT and SOD activities (P<0.05). These results demonstrated that sediment burial depth and Cd input had a great influence on the growth of Suaeda salsa, and to some extent, Suaeda salsa could change its biomass allocation and antioxidative enzyme activities to adapt to severe environments.

The underlying microbial mechanism of epizootic rabbit enteropathy triggered by a low fiber diet.

Epizootic rabbit enteropathy (ERE) is reproduced successfully in the present study by feeding rabbits a low-fibre diet, and high-throughput sequencing and quantitative real-time PCR (qPCR) analysis were applied to examine the microbial variations in the stomach, small intestine and caecum. The evenness was disturbed and the richness was decreased in the ERE groups. When the rabbits were suffering from ERE, the abundance of the Firmicutes was decreased in three parts of the digestive tract, whereas the Proteobacteria was increased in the stomach and caecum, the Bacteroidetes and Verrucomicrobia were increased in the small intestine. Correlation analysis showed that the reduced concentrations of TVFA and butyrate in the caeca of the ERE group were attributed to the decreased abundances of genera such as Lactobacillus, Alistipes and other fibrolytic bacteria and butyrate- producing bacteria such as Eubacterium and Faecalibacterium. It is concluded that, in terms of microorganisms, the overgrowth of Bacteroides fragilis, Clostridium perfringen, Enterobacter sakazakii and Akkermansia muciniphila and inhibition of Bifidobacterium spp. and Butyrivibrio fibrisolvens in the stomach, small intestine and caecum resulted in a decrease in butyrate yield, leading to the incidence of ERE, and the probability of developing ERE could be manipulated by adjusting the dietary fibre level.

[Efficacy of real-time PCR for detecting Clostridium difficile infection: comparison with enzyme-linked fluorescent spectroscopy-based approaches].

OBJECTIVE: To evaluate the diagnostic efficacy of real?time polymerase chain reaction (q?PCR) for Clostridium difficile infection (CDI) in comparison with routine culture and enzyme?linked fluorescent spectroscopy?based aprroaches. METHODS: Stool samples were collected from suspected CDI cases in General Hospital of Guangzhou Military Command of PLA between May and December in 2016. All the samples were examined with 3 methods, namely enzyme?linked fluorescent spectroscopy for detecting Clostridium difficile toxin A/B (CDAB), detection of glutamate dehydrogenase (GDH), and q?PCR for amplification of Clostridium difficile?specific gene tpi and toxin gene (tcdA/tcdB), with the results of fecal culture as the reference for evaluating the diagnostic efficacy of the 3 methods. RESULTS: Of the total of 70 fecal samples, 13 (18.57%) were found to be positive for Clostridium difficile, including toxin?producing strains in 6 (8.57%) samples. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic coincidence rate of q?PCR for tpi were 92.31%, 91.23%, 70.59%, 98.11% and 91.43%, respectively, which were significantly higher than those of GDH test (84.62%, 84.21%, 55.00%, 96.00%, and 84.29%, respectively; Χ2=24.881, P<0.001). The sensitivity of q?PCR for tcdA/cdB was significantly higher than that of enzyme?linked fluorescent spectroscopy for CDAB in detecting CDI (66.67% vs 33.33%; Χ2=35.918, P<0.001). CONCLUSION: Both CDAB detection and q?PCR have a high specificity in detecting CDI, but GDH detection has a good sensitivity, and all these 3 methods have a high negative predictive value. Compared with other detection methods, amplification of tpi and tcdA/tcdB using q?PCR allows more rapid, sensitive and specific detection of CDI.