RNA-Seq reveals transcriptomic interactions of Bacillus subtilis natto and Bifidobacterium animalis subsp. lactis in whole soybean solid-state co-fermentation.

Bifidobacteria are anaerobes and are difficult to culture in conventional fermentation system. It was observed that Bacillus subtilis natto enhanced growth of Bifidobacterium animalis subsp. lactis v9 by about 3-fold in a whole soybean solid-state co-fermentation, in a non-anaerobic condition. For the purpose of understanding the metabolic interactions between Bif. animalis subsp. lactis v9 and Ba. subtilis natto, the transcriptome of Bif. animalis subsp. lactis v9 and Ba. subtilis natto was analyzed in single and mixed cultures using RNA-Seq. Compared with the single culture, 459 genes of Bif. animalis subsp. lactis v9 were up regulated and 21 were down regulated in the mixed culture with Ba. subtilis natto, with more than 2-fold difference. Predictive metagenomic analyses suggested that Ba. subtilis natto up regulated transport functions, complex carbohydrates and amino acid metabolism, DNA repair, oxydative stress-related functions, and cell growth of Bif. animalis subsp. lactis v9. In the mixed culture with Bif. animalis subsp. lactis v9, only 3 transcripts of Ba. subtilis natto were over-expressed and 3115 were under-expressed with more than 2-fold difference. The highest down-regulated genes were those involved in carbohydrate and amino acid metabolism. The data presented here demonstrated a parasitic-like interaction regulated at the transcription level, between Ba. subtilis natto and Bif. animalis subsp. lactis in the mixed culture. The over-expression of genes involved in substrate uptake and metabolism in Bif. animalis subsp. lactis in the mixed culture nevertheless, led to its higher cell concentration in the nutrient rich whole soybean medium.

[Diagnostic value of combined modified Alvarado scores and computed tomography imaging in the pathological types of acute appendicitis in adults].

OBJECTIVE: To explore the diagnostic value of combined modified Alvarado scores (MAS) and computed tomography imaging in the pathological types of acute appendicitis in adults. METHODS: Clinical data of a total of 396 adult patients with acute appendicitis confirmed by surgery and pathology were analyzed retrospectively from June 2007 to July 2010. Case-control study was used to investigate the MAS. CT signs were studied in 115 patients who underwent preoperative CT scan. Univariable analysis was performed using each indicator among different pathological types. Discriminant classification was formed by applying significant variables identified from univariable analysis and a Fisher discriminant function was created. RESULTS: Twenty three variables were statistically significant among different pathological types after univariable analysis(P<0.05) and were selected for discriminant analysis. Six variables including temperature(X1), leucocyte count(X2), the proportion of neutrophil(X3), MAS points(X4), periappendiceal fat stranding(X5), and extraluminal air(X6) were enrolled. The discriminant function equation was Y1=0.012X1+0.041X2+0.069X3-0.039X4+2.653X5+1.418X6, Y2=0.327X1+0.041X2-0.034X3-0.140X4-1.114X5+2.982X6. The accuracy was 76.5%(88/115) in retrospective assessment and 77.8%(21/27) in prospective assessment. CONCLUSION: The combined use of MAS and CT imaging signs is useful in identifying the pathological types of acute appendicitis in adults, so it is helpful in choosing reasonable therapeutic option for surgeons.