Research progress on nutritional support in the neonatal and pediatric populations receiving extracorporeal membrane oxygenation.

Nutritional support is crucial for the prognosis of children supported by extracorporeal membrane oxygenation (ECMO). This article discusses the latest research progress and guideline recommendations for nutritional support during ECMO. We summarize the nutritional status and evaluation of ECMO patients, nutritional support methods and timing, trace elements, the impact of continuous renal replacement therapy (CRRT), and energy requirements and algorithms. The article shows that malnutrition is high in ECMO patients compared to other critically ill patients, with nearly one-third of patients experiencing a decrease in nutritional indicators. The timing of the initiation of nutrition is very important for the nutritional status of the child. Early enteral nutrition can improve patient prognosis, which is the most commonly used, with parenteral nutrition as a supplement. However, the proportion of enteral nutrition is relatively low, and a stepwise nutrition algorithm can determine when to initiate early enteral nutrition and parenteral nutrition. Malnourishment during critical illness have been associated with increased morbidity as well as increased mortality. Nutritional status should be evaluated at admission by screening tools. In addition, changes in the levels of several metabolites in vivo, such as blood lipids, carnitine, and thiamine, can also reflect the degree of nutritional deficiency in critically ill children. This article provides a reference for the implementation of nutrition of pediatric ECMO patients and further research on nutritional support.

Metagenome of Gut Microbiota Provides a Novel Insight into the Pathogenicity of Balantioides coli in Weaned Piglets.

Balantioides coli plays an important role in the diarrhea of weaned piglets, but its pathogenic potential and interaction with gut microbes remain unclear. To investigate the impact of B. coli colonization on the gut bacterial structure and function of weaned piglets, a metagenomic analysis based on shotgun sequencing was performed on fresh fecal samples collected from ten B. coli-colonized piglets and eight B. coli-free ones in this study. The results showed that decreasing diversity and shifted composition and function of the bacterial community were detected in the weaned piglets infected by B. coli. In contrast to the B. coli-negative group, the relative abundances of some members of the Firmicutes phylum including Clostridium, Ruminococcus species, and Intestinimonas butyriciproducens, which produce short-chain fatty acids, were significantly reduced in the B. coli-positive group. Notably, some species of the Prevotella genus (such as Prevotella sp. CAG:604 and Prevotella stercorea) were significantly increased in abundance in the B. coli-positive piglets. A functional analysis of the gut microbiota demonstrated that the differential gene sets for the metabolism of carbohydrates and amino acids were abundant in both groups, and the more enriched pathways in B. coli-infected piglets were associated with the sugar-specific phosphotransferase system (PTS) and the two-component regulatory system, as well as lipopolysaccharide (LPS) biosynthesis. Furthermore, several species of Prevotella were significantly positively correlated to the synthesis of lipid A, leading to the exporting of endotoxins and, thereby, inducing inflammation in the intestines of weaned piglets. Taken together, these findings revealed that colonization by B. coli was distinctly associated with the dysbiosis of gut bacterial structure and function in weaned piglets. Lower relative abundances of Clostridiaceae and Ruminococcaceae and higher abundances of Prevotella species were biomarkers of B. coli infection in weaned piglets.

Comparative Genomic and Transcriptomic Profiling Revealed the Molecular Basis of Starch Promoting the Growth and Proliferation of Balantioides coli.

Carbohydrates are the main source of nutrition for B. coli, supplying energy for cell growth and development. The research aimed at investigating the mechanism of starch on the growth and replication of B. coli. Single-cell separation was used to isolate single trophozoites of B. coli under a stereomicroscope, transcriptomic profiling was conducted based on the SMART-seq2 single-cell RNA-seq method. Comparative genomic analysis was performed on B. coli and eight other ciliates to obtain specific and expanded gene families of B. coli. GO and KEGG enrichment analysis were used to analyze the key genes of B. coli under the action of starch in the present study. The results of single-cell RNA-seq depicts starch affected the growth and replication of B. coli in two ways: (1) the cell cycle was positively promoted by the activation of the cAMP/PKA signaling pathway via glycolysis; (2) the cell autophagy was suppressed through the PI3K/AKT/mTOR pathway. Genes involved in endocytosis, carbohydrate utilization, and the cAMP/PKA signaling pathway were highly enriched in both specific and expanded gene families of B. coli. Starch can be ingested and hydrolyzed into glucose, in turn affecting various biological processes of B. coli. The molecular mechanism of the effect of starch on the growth and proliferation of B. coli by promoting cell cycle and inhibiting the autophagy of trophozoites has been elucidated in our study.

Neospora caninum inhibits tumor development by activating the immune response and destroying tumor cells in a B16F10 melanoma model.

BACKGROUND: Melanoma is a malignant tumor with a high mortality rate. Some microorganisms have been shown to activate the immune system and limit cancer progression. The objective of this study is to evaluate the anti-melanoma effect of Neospora caninum, a livestock pathogen with no pathogenic activity in humans. METHODS: Neospora caninum tachyzoites were inoculated into a C57BL/6 mouse melanoma model by intratumoral and distal subcutaneous injections. Tumor volumes were measured, and cell death areas were visualized by hematoxylin and eosin staining and quantified. Apoptosis in cell cultures and whole tumors was detected by propidium iodide (PI) and TUNEL staining, respectively. Cytokine and tumor-associated factor levels in tumors and spleens were detected by real-time quantitative polymerase chain reaction. Infiltration of macrophages and CD8+ T cells in the tumor microenvironment (TME) were detected by immunohistochemistry with anti-CD68 and anti-CD8 antibodies, respectively. Finally, 16S rRNA sequencing of mice cecal contents was performed to evaluate the effect of N. caninum on gut microbial diversity. RESULTS: Intratumoral and distal subcutaneous injections of N. caninum resulted in significant inhibition of tumor growth (P < 0.001), and more than 50% of tumor cells were dead without signs of apoptosis. Neospora caninum treatment significantly increased the mRNA expression levels of IL-12, IFN-γ, IL-2, IL-10, TNF-α, and PD-L1 in the TME, and IL-12 and IFN-γ in the spleen of tumor-bearing mice (P < 0.05). An increase in the infiltration of CD8+ T cells and macrophages in the TME was observed with these cytokine changes. Neospora caninum also restored the abundance of gut microbiota Lactobacillus, Lachnospiraceae, Adlercreutzia, and Prevotellaceae associated with tumor growth, but the changes were not significant. CONCLUSION: Neospora caninum inhibits B16F10 melanoma by activating potent immune responses and directly destroying the cancer cells. The stable, non-toxic, and efficacious properties of N. caninum demonstrate the potential for its use as a cancer treatment.

Modified DMEM xenic culture medium for propagation, isolation and maintenance of Balantioides coli.

Balantioides coli is a known ciliated zoonotic protozoan that mainly causes diarrhea in humans and pigs. An efficient and reliable culture system for this parasite remains unavailable until now. In this study, a modified Dulbecco's modified eagle medium (DMEM) with pH 7.0-7.5, containing 5 mg/mL starch and 20% new calf serum, was optimized for propagation of B. coli at 28°C-32°C. At the growth-peaking stage, the average trophozoite density was up to 12,970 trophozoites per milliliter. A reproducible protocol for isolation and maintenance of this parasite was also developed based on the modified DMEM culture medium. Moreover, cloning results of B. colipopulations showed that 250 trophozoites in 3 mL modified DMEM medium were the minimal number of trophozoites that propagated to the growth-peaking stage, and finally obtained the individual population. However, less than 250 trophozoites failed to continuously grow in the modified DMEM culture medium under the optimal conditions for growth of B. coli. These data showed that the modified DMEM culture medium is an ideal and efficient medium for propagation and maintenance of B. coli in vitro and will help studies on its biology, genome, transcriptome, proteome, and drug screening.