Deoxynivalenol: toxicological profiles and perspective views for future research

Deoxynivalenol (DON) is a secondary metabolite mainly produced by the fungi Fusarium in agricultural crops, widely existing in feeds and cereal-based foodstuffs. Because of the high occurrence and potentials to induce a variety of toxic effects on animals and humans, DON has been a very harmful exogenous dietary toxicant threating public health. The focus of this review is to summarise the DON-induced broad spectrum of adverse health effects, to probe the current state of knowledge of combined toxicity of DON with other mycotoxins and its derivatives, and to put forward prospective ideas that multi-generational toxicity of DON and its overall impacts on intestinal-immuno-neuroendocrine system could receive more attention in future investigations. The general aim is to provide a scientific basis for the necessity to re-consider risk-assessment and regulations.

PRDX2 plays an oncogenic role in esophageal squamous cell carcinoma via Wnt/β-catenin and AKT pathways

PURPOSE

To investigate the role of PRDX2 in esophageal carcinoma (ESCA).

METHODS

The expression of PRDX2 was detected in ESCA tissues. And PRDX2 expression in two ESCA cell lines was knocked down. Cell proliferation, metastasis and invasion were detected in these cells.

RESULTS

Here, we found that PRDX2 expression was significantly increased in ESCA tissues and was associated with a poor prognosis in ESCA patients. In addition, PRDX2 expression was significantly associated with pathological grading, infiltration degree and 5-year survival time in ESCA patients. Next, we knocked down PRDX2 expression by PRDX2-shRNA transfection in two ESCA cell lines, Eca-109 and TE-1. Proliferation analysis indicated that in vitro PRDX2 knockdown decreased growth and clone formation of ESCA cells. Scratch and transwell assays indicated that cell migration and invasion were significantly inhibited by PRDX2 knockdown. In addition, PRDX2 knockdown inhibited cell cycle of ESCA cells and down-regulated Cyclin D1-CDK4/6. Moreover, PRDX2 knockdown regulated proteins involved in mitochondrial-dependent apoptosis, including increased Bax and Caspase9/3 and decreased Bcl2. Mechanism investigation indicated that PRDX2 knockdown led to inactivation of Wnt/β-catenin and AKT pathways.

CONCLUSIONS

Our data suggest that PRDX2 may function as an oncogene in the development of ESCA via regulating Wnt/β-catenin and AKT pathways. Our study fills a gap in the understanding of the role of PRDX2 in ESCA and provides a potential target for ESCA treatment.

Association between Skeletal Muscle Strength and Dysphagia among Chinese Community-Dwelling Elderly Adults

OBJECTIVES

Swallowing disorder is a health burden for the elderly in China. This study aimed to investigate the prevalence of dysphagia and to test the association between skeletal muscle strength and swallowing problems among community-dwelling older adults.

DESIGN

A cross-sectional study.

SETTING

Community-dwelling Chinese elderly in China.

PARTICIPANTS

3361 adults aged 65 years or above were involved, among which 1740 (51.8%) were female, with average age of 72.64 (Standard deviation, SD=6.10) years old.

MEASUREMENTS

Handgrip strength (HGS) was used to evaluate skeletal muscle strength. Dysphagia assessment was performed using the Eating Assessment Tool-10 (EAT-10) and the 30mL water swallow test (WST). Binary logistic regression was used to evaluate the relationship between skeletal muscle strength and dysphagia, and covariates as age, gender, material status, etc. were adjusted.

RESULTS

The prevalence of dysphagia were 5.5% and 12.9%, screened by EAT-10 and 30mL WST respectively. Participants with dysphagia showed lower HGS (21.73 ± 9.20 vs. 25.66 ± 11.32, p<0.001, by EAT-10; 20.26 ± 9.88 vs. 26.22 ± 11.28, p<0.001, by WST). The adjusted model suggested that muscle strength is a protective factor for swallowing disorders (adjusted OR=0.974, 95%CI: 0.950-0.999, by EAT-10; adjusted OR=0.952, 95%CI: 0.933-0.972, by WST). Subgroup analyses of WST found the effects were significant among participants aged in 70-74 years group and ≥75 years group, rather than those aged under 70.

CONCLUSION

Dysphagia was significantly associated with skeletal muscle strength among the community-dwelling elderly population. Effective interventions should be taken to manage the decline of muscle strength for the older adults, especially early prevention before 70 years old.

Metabolomics Changes of Serum in Rats Dying from Untypical Electric Injury

Abstract

Objective To study the differential metabolites of serum in rats dying from untypical electric injury by ¹H nuclear magnetic resonance （¹ NMR）-based metabolomics methods, in order to provide clues for identification of death from antemortem untypical electric injury and instant postmortem electric injury. Methods Models of rats dying from untypical electric injury, instant postmortem electric injury, mechanical asphyxia, mechanical injury, and high temperature injury were established. The rats in control group were executed without any treatment. The serums of rats from every group were detected by ¹H NMR-based metabolomics technology to screen differential metabolites. Results The rats dying from untypical electric injury group was compared with those from mechanical asphyxia group, mechanical injury group, high temperature injury group, and control group, respectively. Four chemical shift points with diagnostic value, and their corresponding metabolites were screened. These chemical shift points contained many small molecules, such as alcohols, phenols, sugars, amino acids, etc. The death from untypical electric injury group was compared with those from instant postmortem electric injury group and control group, and then eight chemical shift points with diagnostic value and their corresponding metabolites were screened. These chemical shift points contained small molecules, such as sugars, amino acids, esters, nucleic acids, etc. Conclusion The ¹H NMR-based metabolomics technology can identify differential metabolites of serum in rats dying from untypical electric injury, therefore it may provide a basis for the diagnosis of death from untypical electric injury and the identification of antemortem electric injury and instant postmortem electric injury.

Abstract LB-B17: Uncovering novel cancer therapeutics using the Exoneural Medicines Platform: The role of innervation in cancer

Peripheral nerves were first described as a component of tumors in the late 19th century. In the mid-20th century early preclinical studies indicated that tumor cells could recruit innervation from spinal cord ganglia and that stress promotes tumorigenesis. Within the last 10 years improvements in technologies allowing neuronal tracking and regulation of neuronal function have uncovered a role for both autonomic and sensory innervation in multiple tumor types. Initial studies have implicated this biology in prostate, pancreatic, gastric and breast cancer (among others) and point to a role for nerves in initiation, maintenance and metastasis of tumors. The stimulation of tumor cell growth by neural growth factors, the recruitment of neurites by tumor cells, the invasion and migration of tumor cells along nerves (perineural invasion), and the role of innervation in driving tumor angiogenesis are just a few examples of how peripheral nerves interact with the tumor microenvironment. Indeed, an argument could be made that innervation of tumors should be considered a hallmark of cancer. We describe here a biological platform that can define and decode the role of neural signaling in cancer. This platform, which we call Exoneural Medicines Platform ™, has 6 technical components: 1) co-culture models of primary neurons with both tumor and immune cells, 2) advanced imaging modalities to define the neural component of tumors, 3) AAV and transgenic tools that allow regulation of neurons proximal to tumors in vivo and in vitro, 4) neural-focused functional genomics, 5) neural-focused bioinformatics, and 6) a neuropharmacopeia compound library for probing relevant biological pathways and identification of advanced starting points for drug discovery. We show here how the platform is being employed to characterize this exciting new space in cancer biology and to identify new drivers of disease.

Citation Format: Shan Lou, Alexandria Fink, Jay Wang, Jesse Turner, Monica Thanawala, Garmen Yuen, Alexandra Lantermann, Jenny Shu, Hongyue Dai, Pearl Huang, Jonathan Hurov. Uncovering novel cancer therapeutics using the Exoneural Medicines Platform: The role of innervation in cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr LB-B17. doi:10.1158/1535-7163.TARG-19-LB-B17

Methionine and arginine supplementation alter inflammatory and oxidative stress responses during lipopolysaccharide challenge in bovine mammary epithelial cells in vitro

Mastitis, inflammation of the udder, is one of the most common diseases hampering milk yield of dairy cows. Methionine (Met) and arginine (Arg) are key nutrients with potential to regulate inflammation and oxidative stress. The aim of this study was to evaluate the effect of increased supply of Met and Arg on mRNA and protein abundance associated with innate immune response and redox balance during lipopolysaccharide (LPS) stimulation in primary bovine mammary epithelial cells (BMEC). Primary BMEC (n = 4 replicates per treatment) were pre-incubated for 12 h in media with the following amino acid combinations: ideal profile of amino acids (control; Con), increased Met supply (incMet), increased Arg supply (incArg), and increased supply of Met and Arg (incMetArg). Subsequently, cells were challenged with or without LPS (1 µg/mL) and incubated for 6 h. Data were analyzed as a 2 × 2 × 2 factorial using the MIXED procedure of SAS 9.4 (SAS Institute Inc., Cary, NC). The downregulation of SLC36A1 and SLC7A1 mRNA abundance induced by LPS was attenuated in the incArg cultures. Although challenge with LPS led to lower abundance of proteins related to the antioxidant response (NFE2L2, NQO1, GPX1), lower levels of ATG7, and lower mRNA abundance of GPX3, we found little effect in cultures with incMet or incArg. Cultures with incMet, incArg, or incMetArg led to attenuation of the upregulation of SOD2 and NOS2 induced by LPS. Abundance of phosphorylated p65 (RELA) was greater after LPS stimulation, but the response was attenuated in cultures with incMet. The greater ratio of pRELA to total RELA in responses to LPS was also attenuated in cultures with incMetArg. The greater mRNA abundance of the proinflammatory cytokine IL1B induced by LPS was attenuated in cultures with incMet, and the same trend induced by LPS on CXCL2 was also alleviated in cultures with incArg. Overall, the data suggest that greater supply of Met and Arg alleviated the proinflammatory responses triggered by LPS through controlling the abundance of proinflammatory cytokines and chemokines and activity of NF-κB. Little benefit on oxidative stress induced by LPS challenge in BMEC was detected with greater supply of Met and Arg.

A Traditional Chinese Patent Medicine ZQMT for Neovascular Age- Related Macular Degeneration: A Multicenter Randomized Clinical Trial

BACKGROUND

Anti-VEGF agent ranibizumab has been extensively used as a standard treatment for wet AMD. We investigated whether traditional Chinese medicine could serve as a complementary therapy for this disease.

METHODS

144 patients with neovascular age-related macular degeneration received either intravitreal ranibizumab treatment as needed plus placebo or intravitreal ranibizumab treatment as needed plus an FDA approved traditional Chinese patent medicine named ZQMT. Both groups received treatment for 24 weeks. The primary outcome was the mean change of visual acuity at week 24 as compared to the baseline.

RESULTS

We found that intravitreal ranibizumab treatment plus ZQMT was non-inferior to the treatment with intravitreal ranibizumab alone in improving visual acuity scores at week 24 with patients in both groups who gained substantial numbers of letters. In addition, we found that ZQMT treatment resulted in significant improvements in reducing retinal hemorrhage, fluid, and lesion size. Importantly, administration of ZQMT reduced the number of needed ranibizumab injections (P<0.0001, analysis of variance) in wet AMD patients leading to a significant reduction of drug cost.

CONCLUSION

The combinatory therapy of ranibizumab and traditional Chinese patent medicine ZQMT had equivalent effects on visual acuity improvement and safety profiles as the ranibizumab treatment alone. Ranibizumab injections coupled with ZQMT offer therapeutic advantages in terms of reduction of retinal lesions and ease the financial burden of patients undergoing treatment by reducing the frequency of necessary ranibizumab injections.

[Analysis on current status and influential factors of occupational stress among couriers]

Objective: To investigate the current status and influencing factors of occupational stress among couriers. Methods: Couriers (n=925) were selected on this study used cluster sampling method from January to March 2018. They were from SF and Zhongtong Express Co., Ltd., on the Wechat platform, and surveyed by a job stress questionnaire based on a job demand-control model.Valid questionnaires(n=617) were obtained. Results: A total of 418 workers were occupational stress positive (67.7%). The results of Chi-square analysis showed that there were significant differences in occupational stress among workers categorized by job position, working years, mealtime, sleeping time, and weekly work time (P<0.05). The multivariate logistic analysis indicated that non-regular meals, short-term sleep and less than 0.5 working years were risk factors for occupational stress(P<0.05). Conclusion: Couriers generally have occupational stress. The main influencing factors are job position, working years mealtime, sleeping time, and weekly work time. It is necessary to guide healthy lifestyle, rationally organize labor and assign tasks, and improve working environment to relieve their occupational stress.

Short communication: Supply of methionine during late pregnancy enhances whole-blood innate immune response of Holstein calves partly through changes in mRNA abundance in polymorphonuclear leukocytes

The supply of methionine (Met) in late pregnancy can alter mRNA abundance of genes associated with metabolism and immune response in liver and polymorphonuclear leukocytes (PMN) of the neonatal calf. Whether prenatal supply of Met elicits postnatal effects on systemic inflammation and innate immune response of the calf is not well known. We investigated whether enhancing the maternal supply of Met via feeding ethyl-cellulose rumen-protected Met (RPM) was associated with differences in calf innate immune response mRNA abundance in PMN and systemic indicators of inflammation during the first 50 d of life. Calves (n = 14 per maternal diet) born to cows fed RPM at 0.09% of diet dry matter per day (MET) for the last 28 ± 2 d before calving or fed a control diet with no added Met (CON) were used. Blood for biomarker analysis and isolation of PMN for innate immune function assays and mRNA abundance was harvested at birth (before colostrum feeding) and at 7, 21 and 50 d of age. Whole blood was challenged with enteropathogenic bacteria (Escherichia coli 0118:H8) and phagocytosis and oxidative burst of neutrophils and monocytes were quantified via flow cytometry. Although concentration of haptoglobin and activity of myeloperoxidase among calves from both maternal groups increased markedly between 0 and 7 d of age followed by a decrease to baseline at d 21 the responses were lower in MET compared with CON calves. Nitric oxide concentration decreased markedly between 0 and 7 d regardless of maternal group but MET calves tended to have lower overall concentrations during the study. In vitro phagocytosis in stimulated neutrophils increased markedly over time in both CON and MET calves but responses were overall greater in MET calves. Oxidative burst in both neutrophils and monocytes increased over time regardless of maternal treatment. The mRNA abundance of lactate dehydrogenase (LDHA) signal transducer and activator of transcription 3 (STAT3) and S100 calcium binding protein A8 (S100A8) in PMN was overall greater in MET calves. Overall data suggest that increasing the maternal supply of Met during late pregnancy could affect the neonatal calf inflammatory status and innate immune response. Although changes in mRNA abundance could play a role in coordinating the immune response the exact mechanisms merit further study.

Differential expression of toll-like receptor 13 and ribosomal protein L29 in inflammatory lung and brain

Viral dsRNA acts as the paramount pathogen-associated molecular pattern on infection and orchestrates inflammation or immune cascades of the host's tissues. The comparative effects or mechanisms of inflammation or immunity in different organs on viral infections are critical in immunology or virology. To outline the organ-based molecular mechanisms of inflammation or immunity on viral infection, we challenged mice with the viral mimic poly(I:C) and quantified inflammatory cytokines Il-1b and TNF-α in the brain and lung tissues. As cytokines showed differential expression, transcriptome screenings of mouse lung and brain tissues were analyzed. We identified 629 differentially expressed genes (DEGs) in lung and 137 DEGs in brain tissues with a few overlapping genes. Most of those DEGs were interferon-stimulated genes (ISGs) that are involved in the anti-viral defense mechanisms. The expression patterns of viral dsRNA stimulated genes, and consequently, their association with different molecular mechanisms of inflammation and immunity were specific to the organs. The effects of viral mimic were higher in the lung than in the brain in terms of the number of DEGs and ISGs. Interestingly ribosomal protein L29 (Rpl29), a cell surface heparin-binding protein, was upregulated in the brain and downregulated in the lung. The contrasting expression of Rpl29 gene might be responsible for tissue-specific inflammatory responses in lung and brain tissue on virus infection. In addition, the upregulation of Tlr13, a dsRNA and bacterial 23s rRNA receptor, in the poly(I:C)-stimulated mouse lungs suggests its important role in lung inflammatory responses. It is likely that the combined effects of these genes orchestrate the organ-specific inflammatory or immune responses. Our findings would be beneficial to explore new insights in inflammation and immunity against many critical viral diseases.

Interleukin-23 deficiency alters thymic selection in lupus-prone mice

We have previously reported that IL-23 receptor deficiency in MRL.lpr mice ameliorates lupus by altering the balance of pro- and anti-inflammatory cytokines in secondary lymphoid organs. As IL-23 may also impact thymic selection, we evaluated the effect of IL-23 on thymic T cell development in lupus-prone mice. We generated IL-23p19-deficient MRL.lpr mice and harvested their thymus at 8 weeks of age. We found that the late stage double negative DN4 population was increased in IL-23p19^-/- MRL.lpr mice when compared to IL-23p19^+/+ MRL.lpr mice. Despite this, mature thymocytes (CD24^-TCRβ⁺) were decreased by more than 50% in the IL-23p19-deficient mice versus wild-type controls. This was associated with a decrease in the generation of CD8⁺ T cells, possibly through downregulation of the IL-7 receptor. CD8⁺ T cells were not only fewer in numbers but also had decreased expression of the migration-related receptors CD44 and CD62L in the thymus and spleens of IL-23p19-deficient versus wild-type mice. We propose that IL-23 promotes the development of lupus-like autoimmunity not only through T cell polarization and cytokine production in the peripheral lymphoid organs but also by influencing T cell thymic development.

Validation of a predictive method for sunscreen formula evaluation using gene expression analysis in a Chinese reconstructed full-thickness skin model

OBJECTIVE

This study aimed to establish a predictive in vitro method for assessing the photoprotective properties of sunscreens using a reconstructed full-thickness skin model.

MATERIALS AND METHODS

A full-thickness skin model reconstructed with human fibroblasts and keratinocytes isolated from Chinese skin was exposed to daily UV radiation (DUVR). We examined the transcriptomic response, identifying genes for which expression was modulated by DUVR in a dose-dependent manner. We then validated the methodology for efficacy evaluation of different sunscreens formulas.

RESULTS

The reconstructed skin model was histologically consistent with human skin, and upon DUVR exposure, the constituent fibroblasts and keratinocytes exhibited transcriptomic alterations in pathways associated with oxidative stress, inflammation and extracellular matrix remodelling. When used to evaluate sunscreen protection on the model, the observed level of protection from UV-induced gene expression was consistent with the corresponding protection factors determined clinically and allowed for statistical ranking of sunscreen efficacy.

CONCLUSIONS

Within this study we show that quantification of gene modulation within the reconstructed skin model is a biologically relevant approach with sensitivity and predictability to evaluate photoprotection products.

[Effects of budesonide aerosol inhalation on the immunological functions of peripheral dendritic cells in patients with allergic rhinitis]

Objective: To investigate the immunologic functional changes of peripheral dendritic cells (DC) in patients with allergic rhinitis (AR) during the treatment by budesonide aerosol inhalation.Method:25 patients with moderate to severe persistent AR were concluded in current study, and they were given budesonide aerosol inhalation for 8 weeks. AR related nasal symptom scores and indices, peripheral DC counts and percentages as well as their activation before and 4 weeks, 8 weeks after treatment were determined.Result:There were significant decrease in nasal symptom scores, eosinophils, AR specific IgE antibodies after 4 and 8 weeks of treatment. The overall clinical efficiency reached 88% at the end of the treatment. Peripheral DC counts and DC/PBMC decreased in comparison with the levels of pre-treatment (P<0.05). Compared with the levels before treatment, DC activation markers CD86 and CD80 reduced to various extent, while glucocorticoid-induced leucine zipper (GILZ) positive cells gradually elevated (P<0.05). In the DC secreted IL-10 decreased against the treatment duration, while IFN-γ from DC conditioned T cells statistically increased after treatment (P<0.05). Conclusion:Budesonide suppressed DC activation and maturation, which might redirect DC-involved Th2 response, in turn alleviating the AR symptoms.

[Efficacy analysis of T type tube dilatation in adult cervical tracheal stenosis]

Objective:To investigate the efficacy, recurrence and strategy of T silicone tube dilatation for cicatricial stenosis of cervical trachea in adults.Method:Cinical data of 37 cases with the cervical tracheal stenosis were retrospectively analyzed, who were firstly treated by T shape silicone tube dilation for at least 10 months, from Jun 2006 to Jun 2016.Result:In 37 adult patients with cicatricial stenosis of the trachea, 29 cases were caused by tracheal intubation or incision, 6 cases were traumatic, and 2 cases were multiple osteochondritis. Twentythree cases were experienced one time surgery and extubated successfully, 8 cases were experienced 2 times and more than 2 times surgery (sternohyoid muscle flap pedicled hyoid bone with T tube expansion in 3 cases, tracheal endoscopic dilatation in 2 cases, T tube dilatation in 3 cases), extubation success rate of 83.7%. Among the 6 cases with failure of extubation, 2 cases were multiple osteochondritis, 3 cases had severe scar constitution, 1 cases were lost of follow-up.Conclusion:T type silicon tube expansion for the treatment of adult cervical tracheal stenosis can be achieved relatively high decannulation rate. For recurrent stenosis, we can consider to use various methods of expansion, and improve the decannulation rate. Intratracheal granulation tissuextubation after exbation should be observed for at least 1 month. For concurrent with polychondritis and severe scar the constitution, the operation should be carefully chosen.

Circulating T Cell Subpopulations Correlate With Immune Responses at the Tumor Site and Clinical Response to PD1 Inhibition in Non-Small Cell Lung Cancer

Agents targeting the PD1-PDL1 axis have transformed cancer therapy. Factors that influence clinical response to PD1-PDL1 inhibitors include tumor mutational burden, immune infiltration of the tumor, and local PDL1 expression. To identify peripheral correlates of the anti-tumor immune response in the absence of checkpoint blockade, we performed a retrospective study of circulating T cell subpopulations and matched tumor gene expression in melanoma and non-small cell lung cancer (NSCLC) patients. Notably, both melanoma and NSCLC patients whose tumors exhibited increased inflammatory gene transcripts presented high CD4⁺ and CD8⁺ central memory T cell (CM) to effector T cell (Eff) ratios in blood. Consequently, we evaluated CM/Eff T cell ratios in a second cohort of NSCLC. The data showed that high CM/Eff T cell ratios correlated with increased tumor PDL1 expression. Furthermore, of the 22 patients within this NSCLC cohort who received nivolumab, those with high CM/Eff T cell ratios, had longer progression-free survival (PFS) (median survival: 91 vs. 215 days). These findings show that by providing a window into the state of the immune system, peripheral T cell subpopulations inform about the state of the anti-tumor immune response and identify potential blood biomarkers of clinical response to checkpoint inhibitors in melanoma and NSCLC.

bmp3 is Required for Integrity of Blood Brain Barrier by Promoting Pericyte Coverage in Zebrafish Embryos

BACKGROUND

The compromise of blood brain barrier (BBB) integrity is often associated with human hemorrhage stroke and neurodegeneration diseases, including retina diseases, such as age-related macular degeneration and diabetic retinopathy. Brain pericytes play pivotal roles in regulation and maintenance of BBB integrity. However, the mechanisms underlying brain pericyte development to establish BBB integrity remain unclear.

METHODS

Zebrafish transgenic lines Tg(flk1:GFP; gata1:dsRed), Tg(flk1:GFP), Tg(fli1:GFP) and Tg(BRE:GFP) were used in this work. The functional studies of bmp3 were performed by mopholino oligonucleotide (MO) injection, dye-based permeability assay, RT-PCR, in vivo imaging, immunofluorescence staining and statics analysis.

RESULTS

Here we report that bmp3 regulates BBB integrity in zebrafish brain by promoting pericyte development. Knockdown of bmp3 with injection of bmp3-MO causes intracerebral hemorrhage in zebrafish embryos. Meanwhile, disruption of bmp3 function by bmp3-MO injection impairs cerebral pericyte coverage in zebrafish embryos. Mechanistically, knockdown of bmp3 disrupts the pattern and activities of BMP signaling in zebrafish brain, thus probably disrupting the balance of TGFβ/BMP signaling in zebrafish embryos.

CONCLUSION

In summary, our data shows that bmp3 regulates BBB integrity potentially by promoting pericyte development.

The impact of neurally adjusted ventilatory assist mode on respiratory severity score and energy expenditure in infants: a randomized crossover trial

OBJECTIVE

Examine respiratory severity scores (RSS) (mean airway pressure × fraction of inspired oxygen) and resting energy expenditure (REE) on neurally adjusted ventilatory assist (NAVA) compared with synchronized intermittent mandatory ventilation with pressure controlled and supported breath (SIMV (PC)PS).

STUDY DESIGN

A randomized, crossover trial in a level IV neonatal intensive care unit. Twenty-four patients were ventilated with NAVA or SIMV (PC) PS for 12 h and then crossed over to the alternative mode for 12 h. The primary outcome (RSS) and additional secondary respiratory outcomes were analyzed.

RESULTS

RSS and measured REE were not different between modes. On NAVA, peak inspiratory pressures were lower (17.8 vs 19.9 cmH₂O (P<0.05)) without higher oxygen requirements. Respiratory rates were higher on NAVA (52 vs 39 (P<0.05)), estimated work of breathing (WOB) (0.01 vs 0.04 J l^-1 (P<0.05)) was improved.

CONCLUSION

NAVA mode can be safe without increase in RSS or REE. Although respiratory rates were higher, this was offset by lower peak inspiratory pressures and WOB during NAVA.