Bolus therapy with 3% hypertonic saline or 0.9% saline in emergency department patients with suspected sepsis: A pilot randomised controlled trial.

OBJECTIVE AND DESIGN: Hypertonic saline administered during fluid resuscitation may mitigate endothelial glycocalyx (EG) shedding and inflammation. The objective of this pilot randomised controlled trial was to measure the effect of hypertonic saline, compared to isotonic saline, on biomarkers of EG shedding and inflammation in emergency department patients with suspected sepsis. METHODS: Patients received either 5 mL/kg of 3% saline (hypertonic group, n = 34) or 10 mL/kg of 0.9% saline (isotonic group, n = 31). Change in serum biomarker concentrations of syndecan-1, hyaluronan, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, interleukin-6, -8, -10, interferon-γ, neutrophil gelatinase-associated lipocalin and resistin were compared from baseline (T0) to after fluid (T1), 3 h (T3) and 12-24 h (T24) later, as was serum osmolality, using linear mixed effects models. RESULTS: The hypertonic group had significantly increased mean serum osmolality compared to the isotonic group at T1 (P < .001) and T3 (P = .004). Minor differences were found in some biomarker outcomes, including a decreased fold-change in syndecan-1 at T1 (P = .012) and in interleukin-10 at T24 (P = .006) in the isotonic group, compared to the hypertonic group. CONCLUSIONS: Although a single bolus of hypertonic saline increased serum osmolality, it did not reduce biomarkers of EG shedding or inflammation, compared to patients that received isotonic saline. TRIAL REGISTRATION: ANZCTR.org.au, ACTRN12611001021965, Registered on 23rd September 2011.

Glycocalyx biomarker syndecan-1 is a stronger predictor of respiratory failure in patients with sepsis due to pneumonia, compared to endocan.

PURPOSE: Endocan, a component of the endothelial glycocalyx (EG), has been linked with respiratory failure in sepsis. This study explored the temporal patterns of three EG biomarkers, including endocan, and their relationships with inflammation and respiratory failure. MATERIALS AND METHODS: Plasma endocan, syndecan-1, and hyaluronan concentrations were measured in Emergency Department (ED) patients with sepsis due to pneumonia (n = 44) on ED arrival (T0), 1 h (T1), 3 h (T3) and 12-24 h (T24) later, with change over time tested using mixed regression models. Biomarker associations with inflammatory cytokine concentrations and with respiratory failure on days 1, 2 or 3, need for mechanical ventilation and 30-day mortality were also tested. RESULTS: Endocan concentration significantly decreased over time (T0-T24, P = 0.003) whereas both syndecan-1 (T0-T3, P = 0.010; T0-T24, P < 0.001) and hyaluronan (T0-T1, P = 0.010; T0-T3, P < 0.001; T0-T24, P = 0.003) significantly increased over time. Increased syndecan-1 was significantly correlated with neutrophil activation biomarkers and significantly increased the odds of respiratory failure (OR 1.18, 95% CI 1.05-1.33, P = 0.004), need for mechanical ventilation (OR 1.24, 95% CI 1.04-1.48, P = 0.014) and 30-day mortality (OR 1.29, 95% CI 1.07-1.55, P = 0.008). CONCLUSION: Syndecan-1, but not endocan, was associated with neutrophil activation and was the best EG biomarker predictor of adverse clinical outcomes.

Resistin and NGAL are associated with inflammatory response, endothelial activation and clinical outcomes in sepsis.

OBJECTIVE AND DESIGN: Resistin and neutrophil gelatinase-associated lipocalin (NGAL) are upregulated in circulating leucocytes in sepsis, but the significance of this is uncertain. We evaluated associations between Resistin and NGAL with endothelial cell activation and clinical outcomes in a prospective observational study in the Emergency Department (ED). METHODS: Serum levels of Resistin, NGAL, inflammatory cytokines (IL-6, IL-10) and soluble endothelial adhesion molecules (VCAM-1, ICAM-1) were measured at defined time points up to 24 h. Patterns and relationships between markers were investigated using linear mixed regression models. Predictive values for clinical outcomes for markers at enrollment were assessed by logistic regression and receiver operator characteristic (ROC) curves. RESULTS: 186 participants (89 septic-shock, 69 sepsis, 28 uncomplicated infection) were compared with 29 healthy controls. Median Resistin and NGAL were higher in uncomplicated infection compared to controls, and in septic shock compared to non-shock sepsis. Resistin and NGAL correlated with IL-6 and IL-10, with VCAM-1 and ICAM-1, and with organ failure. Resistin and NGAL were associated with septic shock but had limited predictive utility for mortality. CONCLUSION: Resistin and NGAL correlate with expression of endothelial cell adhesion molecules in sepsis. Further evaluation of the role of Resistin and NGAL in sepsis pathogenesis is warranted.

Distinct inflammatory responses differentiate cerebral infarct from transient ischaemic attack.

We previously reported on a 26-year-old patient who presented early during a large and eventually fatal cerebral infarct. Microarray analysis of blood samples from this patient demonstrated initially up-regulated and subsequently down-regulated Granzyme B (GzmB) expression, along with progressive up-regulation of genes for S100 calcium binding protein A12 (S100A12) and matrix metalloproteinase 9 (MMP-9). To confirm these findings, we investigated these parameters in patients with suspected stroke presenting within 6h of symptom onset to a single centre. Blood samples were taken at enrolment, then 1h, 3h and 24h post-enrolment for the examination of cellular, protein and genetic changes. Patients with subsequently confirmed ischaemic (n=18) or haemorrhagic stroke (n=11) showed increased intracellular concentrations of GzmB in all cell populations investigated (CD8+, CD8- and Natural Killer [NK] cells). Infarct patients, however, demonstrated significantly reduced GzmB gene expression and increased circulating MMP-9 and S100A12 levels in contrast to transient ischaemic attack (TIA) patients or healthy controls. Furthermore, a pronounced neutrophilia was noted in the infarct and haemorrhage groups, while TIA patients (n=9) reflected healthy controls (n=10). These findings suggest a spectrum of immune response during stroke. TIA showed few immunological changes in comparison to infarct and haemorrhage, which demonstrated inhibition of GzmB production and a rise in neutrophil numbers and neutrophil-associated mediators. This implies a greater role of the innate immune system. These markers may provide novel targets for inhibition and reduction of secondary injury.

Elevation of oxidative stress indicators in a pilot study of plasma following traumatic brain injury.

Traumatic brain injury (TBI) encompasses a broad range of injury mechanisms and severity. A detailed determination of TBI severity can be a complex challenge, with current clinical tools sometimes insufficient to tailor a clinical response to a spectrum of patient needs. Blood biomarkers of TBI may supplement clinical assessments but currently available biomarkers have limited sensitivity and specificity. While oxidative stress is known to feature in damage mechanisms following TBI, investigation of blood biomarkers of oxidative stress has been limited. This exploratory pilot study of a subset of 18 trauma patients with TBI of varying severity, quantifies circulating concentrations of the structural damage indicators S100b, and myelin basic protein (MBP), and the biomarkers of oxidative stress hydroxynonenal (HNE), malondialdehyde (MDA), carboxy-methyl-lysine (CML), and 8-hydroxy-2'-deoxy-guanosine (8-OHDG). Significant increases in circulating S100b, MBP, and HNE were observed in TBI patient samples compared to 8 uninjured controls, and there was a significant decrease in CML. This small exploratory study supports the current literature on S100b and MBP elevation in TBI, and reveals potential for the use of peripheral oxidative stress markers to assist in determination of TBI severity. Further investigation is required to validate results and confirm trends.

Sustained elevation of resistin, NGAL and IL-8 are associated with severe sepsis/septic shock in the emergency department.

OBJECTIVE: To identify biomarkers which distinguish severe sepsis/septic shock from uncomplicated sepsis in the Emergency Department (ED). METHODS: Patients with sepsis underwent serial blood sampling, including arrival in the ED and up to three subsequent time points over the first 24 hours. Messenger RNA (mRNA) levels of 13 genes representing arms of the innate immune response, organ dysfunction or shock were measured in peripheral blood leucocytes using quantitative PCR, and compared with healthy controls. Serum protein concentrations of targets differentially expressed between uncomplicated sepsis and severe sepsis/septic shock were then measured at each time point and compared between the two patient groups. RESULTS: Of 27 participants (median age 66 years, (IQR 35, 78)), 10 had uncomplicated sepsis and 17 had sepsis with organ failure (14 septic shock; 3 had other sepsis-related organ failures). At the time of first sample collection in the ED, gene expression of Interleukin (IL)-10 and Neutrophil Gelatinase Associated Lipocalin (NGAL) were significantly higher in severe sepsis than uncomplicated sepsis. Expression did not significantly change over time for any target gene. Serum concentrations of IL-6, IL-8, IL-10, NGAL and Resistin were significantly higher in severe sepsis than uncomplicated sepsis at the time of first sample collection in the ED, but only IL-8, NGAL and Resistin were consistently higher in severe sepsis compared to uncomplicated sepsis at all time points up to 24 h after presentation. CONCLUSIONS: These mediators, produced by both damaged tissues and circulating leukocytes, may have important roles in the development of severe sepsis. Further work will determine whether they have any value, in addition to clinical risk parameters, for the early identification of patients that will subsequently deteriorate and/or have a higher risk of death.

Live pigs produced from genome edited zygotes.

Transcription activator-like effector nuclease (TALEN) and zinc finger nuclease (ZFN) genome editing technology enables site directed engineering of the genome. Here we demonstrate for the first time that both TALEN and ZFN injected directly into pig zygotes can produce live genome edited pigs. Monoallelic as well as heterozygous and homozygous biallelic events were identified, significantly broadening the use of genome editor technology in livestock by enabling gene knockout in zygotes from any chosen mating.

Mammary gland development is delayed in mice deficient for aminopeptidase N.

Development of the mammary gland requires the coordinated action of proteolytic enzymes during two phases of remodelling. Firstly, new ducts and side-branches thereof need to be established during pregnancy to generate an extensive ductal tree allowing the secretion and transport of milk. A second wave of remodelling occurs during mammary involution after weaning. We have analysed the role of the cell surface protease aminopeptidase N (Anpep, APN, CD13) during these processes using Anpep deficient and Anpep over-expressing mice. We find that APN deficiency significantly delays mammary gland morphogenesis during gestation. The defect is characterised by a reduction in alveolar buds and duct branching at mid-pregnancy. Conversely over-expression of Anpep leads to accelerated ductal development. This indicates that Anpep plays a critical role in the proteolytic remodelling of mammary tissue during adult mammary development.

Derivation and characterization of induced pluripotent stem cells from equine fibroblasts.

Pluripotent stem cells offer unprecedented potential not only for human medicine but also for veterinary medicine, particularly in relation to the horse. Induced pluripotent stem cells (iPSCs) are particularly promising, as they are functionally similar to embryonic stem cells and can be generated in vitro in a patient-specific manner. In this study, we report the generation of equine iPSCs from skin fibroblasts obtained from a foal and reprogrammed using viral vectors coding for murine Oct4, Sox2, c-Myc, and Klf4 sequences. The reprogrammed cell lines were morphologically similar to iPSCs reported from other species and could be stably maintained over more than 30 passages. Immunostaining and polymerase chain reaction analyses revealed that these cell lines expressed an array of endogenous markers associated with pluripotency, including OCT4, SOX2, NANOG, REX1, LIN28, SSEA1, SSEA4, and TRA1-60. Furthermore, under the appropriate conditions, the equine iPSCs readily formed embryoid bodies and differentiated in vitro into cells expressing markers of ectoderm, mesoderm, and endoderm, and when injected into immunodeficient mice, gave raise to tumors containing differentiated derivatives of the 3 germ layers. Finally, we also reprogrammed fibroblasts from a 2-year-old horse. The reprogrammed cells were similar to iPSCs derived from neonatal fibroblasts in terms of morphology, expression of pluripotency markers, and differentiation ability. The generation of these novel cell lines constitutes an important step toward the understanding of pluripotency in the horse, and paves the way for iPSC technology to potentially become a powerful research and clinical tool in veterinary biomedicine.

Milk lacking α-casein leads to permanent reduction in body size in mice.

The major physiological function of milk is the transport of amino acids, carbohydrates, lipids and minerals to mammalian offspring. Caseins, the major milk proteins, are secreted in the form of a micelle consisting of protein and calcium-phosphate.We have analysed the role of the milk protein α-casein by inactivating the corresponding gene in mice. Absence of α-casein protein significantly curtails secretion of other milk proteins and calcium-phosphate, suggesting a role for α-casein in the establishment of casein micelles. In contrast, secretion of albumin, which is not synthesized in the mammary epithelium, into milk is not reduced. The absence of α-casein also significantly inhibits transcription of the other casein genes. α-Casein deficiency severely delays pup growth during lactation and results in a life-long body size reduction compared to control animals, but has only transient effects on physical and behavioural development of the pups. The data support a critical role for α-casein in casein micelle assembly. The results also confirm lactation as a critical window of metabolic programming and suggest milk protein concentration as a decisive factor in determining adult body weight.

Transgenic sheep designed for transplantation studies.

Lentiviral vectors have recently emerged as an efficient method of transgene delivery to the germline of animals. We now demonstrate that combining this efficiency with embryo splitting procedures enables the production of monozygotic twins, one of which is transgenic. We propose that this approach can be used to generate animals in which cell or tissue transplantation can be achieved without the use of immunosuppressive regimes.

Live lambs born from zona-pellucida denuded embryos.

Progress with techniques using zona-pellucida denuded embryos has resulted in the birth of live cattle, pigs, and mice. The application of zona-free methods in sheep has been restricted to in vitro studies. In this report, we demonstrate that live lambs can be produced from zona-free IVF embryos. We are pursuing this method as a prerequisite to developing viral vector co-culture delivery strategies.