Characterization and evaluation of Bacillus isolates for their potential plant growth and biocontrol activities against tomato bacterial wilt

About 200 Bacillus isolates were isolated from tomato and potato rhizosphere and examined for their antagonistic activities against Ralstonia solanacearum T-91, the causal agent of tomato bacterial wilt (TBW), in vitro and in vivo. Four strains, AM1, D16, D29 and H8, have shown high potential of antagonistic activity against the pathogen in laboratory and greenhouse experiments. In greenhouse, 81.1 to 89.0% reduction of disease incidence of TBW was recorded in treated tomato plants with 4 isolates, which also significantly (p > 0.05) increased plant height by 22.7 to 43.7% and dry weight by 47.93 to 91.55% compared with non-treated control. 16SrRNA gene sequence, the biochemical and physiological tests and fatty acid methyl esters analysis assigned strains AM1 and D29 as Bacillus amyloliquefaciens, while strains D16 and H8 as Bacillus subtilis and B. methylotrophicus, respectively. In addition, the 4 strains showed ability to inhibit growth of the three soil-borne fungi, produce indole-3- acetic acid, siderophores and also with exception of strain D16, the other 3 strains were capable of solubilizing phosphate. Therefore, these results suggest that out of 200 isolates, Bacillus stains AM1, D16, D29 and H8 support good antagonistic activity and could be applied as biocontrol agents against TBW under greenhouse conditions beside their potential to promote tomato plants growth.Key words: Tomato, Ralstonia solanacearum, Bacillus spp, biological control, plant growth promotion activitie

Glucose metabolism following human traumatic brain injury: methods of assessment and pathophysiological findings.

The pathophysiology of traumatic brain (TBI) injury involves changes to glucose uptake into the brain and its subsequent metabolism. We review the methods used to study cerebral glucose metabolism with a focus on those used in clinical TBI studies. Arterio-venous measurements provide a global measure of glucose uptake into the brain. Microdialysis allows the in vivo sampling of brain extracellular fluid and is well suited to the longitudinal assessment of metabolism after TBI in the clinical setting. A recent novel development is the use of microdialysis to deliver glucose and other energy substrates labelled with carbon-13, which allows the metabolism of glucose and other substrates to be tracked. Positron emission tomography and magnetic resonance spectroscopy allow regional differences in metabolism to be assessed. We summarise the data published from these techniques and review their potential uses in the clinical setting.This is the final published version. It originally appeared at http://dx.doi.org/10.1007/s11011-014-9628-y

Bioinspired Polymerization of Quercetin to Produce a Curcumin-Loaded Nanomedicine with Potent Cytotoxicity and Cancer-Targeting Potential in Vivo

Nanomedicine has had a profound impact on the treatment of many diseases, especially cancer. However, synthesis of multifunctional nanoscale drug carriers often requires multistep coupling and purification reactions, which can pose major scale-up challenges. Here, we leveraged bioinspired oxidation-triggered polymerization of catechols to synthesize nanoparticles (NPs) from the plant polyphenol quercetin (QCT) loaded with a hydrophobic anticancer drug, curcumin, and functionalized with poly(ethylene glycol) (PEG) for steric stabilization in one reaction step. NPs were formed by base-catalyzed oxidative self-polymerization of QCT in the presence of curcumin and thiol-terminated PEG upon mixing in a universal solvent (dimethyl sulfoxide), followed by self-assembly with the gradual addition of water. Dynamic light scattering and X-ray photoelectron spectroscopy were used to confirm NP PEGylation. Drug loading was verified by UV–vis spectroscopy. Curcumin-loaded NPs were efficiently internalized by CT26 murine colon cancer cells as determined by flow cytometry and confocal microscopy. NPs also demonstrated sustained release and potent cytotoxicity in vitro. Moreover, in vivo imaging of CT26 tumor-bearing Balb/c mice following tail vein injection of DiR-labeled QCT NPs showed steady tumor accumulation of the NPs up to 24 h. This was further supported by significant tumor uptake of curcumin-loaded QCT NPs as measured by flow cytometry analysis of tumor homogenates. Our findings present a greener synthetic route for the fabrication of drug-loaded surface-functionalized NPs from poorly water-soluble plant polyphenols such as QCT as promising anticancer delivery systems

Increased blood glucose is related to disturbed cerebrovascular pressure reactivity after traumatic brain injury.

BACKGROUND: Increased blood glucose and impaired pressure reactivity (PRx) after traumatic brain injury (TBI) are both known to correlate with unfavorable patient outcome. However, the relationship between these two variables is unknown. METHODS: To test the hypothesis that increased blood glucose leads to increased PRx, we retrospectively analyzed data from 86 traumatic brain injured patients admitted to the Neurocritical Care Unit. Data analyzed included arterial glucose concentration, intracranial pressure (ICP), cerebral perfusion pressure (CPP) and end-tidal CO2. PRx was calculated as the moving correlation coefficient between averaged (10 seconds) arterial blood pressure and ICP. One arterial glucose concentration and one time-aligned PRx value were obtained for each patient, during each day until the fifth day after ictus. RESULTS: Mean arterial glucose concentrations during the first 5 days since ictus were positively correlated with mean PRx (Pearson correlation coefficient = 0.25, p = 0.02). The correlation was strongest on the first day after injury (Pearson correlation coefficient = 0.47, p = 0.008). CONCLUSION: Our preliminary findings indicate that increased blood glucose may impair cerebrovascular reactivity, potentially contributing to a mechanistic link between increased blood glucose and poorer outcome after TBI.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s12028-014-0042-

Glycolysis and the pentose phosphate pathway after human traumatic brain injury: microdialysis studies using 1,2-(13)C2 glucose.

Increased 'anaerobic' glucose metabolism is observed after traumatic brain injury (TBI) attributed to increased glycolysis. An alternative route is the pentose phosphate pathway (PPP), which generates putatively protective and reparative molecules. To compare pathways we employed microdialysis to perfuse 1,2-(13)C2 glucose into the brains of 15 TBI patients and macroscopically normal brain in six patients undergoing surgery for benign tumors, and to simultaneously collect products for nuclear magnetic resonance (NMR) analysis. (13)C enrichment for glycolytic 2,3-(13)C2 lactate was the median 5.4% (interquartile range (IQR) 4.6-7.5%) in TBI brain and 4.2% (2.4-4.4%) in 'normal' brain (P<0.01). The ratio of PPP-derived 3-(13)C lactate to glycolytic 2,3-(13)C2 lactate was median 4.9% (3.6-8.2%) in TBI brain and 6.7% (6.3-8.9%) in 'normal' brain. An inverse relationship was seen for PPP-glycolytic lactate ratio versus PbtO2 (r=-0.5, P=0.04) in TBI brain. Thus, glycolytic lactate production was significantly greater in TBI than 'normal' brain. Several TBI patients exhibited PPP-lactate elevation above the 'normal' range. There was proportionally greater PPP-derived lactate production with decreasing PbtO2. The study raises questions about the roles of the PPP and glycolysis after TBI, and whether they can be manipulated to achieve a better outcome. This study is the first direct comparison of glycolysis and PPP in human brain.We gratefully acknowledge financial support as follows. Study support: Medical Research Council (Grant Nos. G0600986 ID79068 and G1002277 ID98489) and National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme). Authors’ support: I.J. – Medical Research Council (Grant no. G1002277 ID 98489) and National Institute for Health Research Biomedical Research Centre, Cambridge; K.L.H.C. – National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); C.G. – the Canadian Institute of Health Research; A.H. – Medical Research Council/ Royal College of Surgeons of England Clinical Research Training Fellowship (Grant no. G0802251) and Raymond and Beverly Sackler Fellowship; D.K.M. and J.D.P. - National Institute for Health Research Senior Investigator Awards; P.J.H. – National Institute for Health Research Professorship, Academy of Medical Sciences/Health Foundation Senior Surgical Scientist Fellowship.This is the accepted manuscript version. The final version is available from the Nature Publishing Group http://www.nature.com/jcbfm/journal/v35/n1/full/jcbfm2014177a.html

Systemic, local, and imaging biomarkers of brain injury: more needed, and better use of those already established?

Much progress has been made over the past two decades in the treatment of severe acute brain injury, including traumatic brain injury and subarachnoid hemorrhage, resulting in a higher proportion of patients surviving with better outcomes. This has arisen from a combination of factors. These include improvements in procedures at the scene (pre-hospital) and in the hospital emergency department, advances in neuromonitoring in the intensive care unit, both continuously at the bedside and intermittently in scans, evolution and refinement of protocol-driven therapy for better management of patients, and advances in surgical procedures and rehabilitation. Nevertheless, many patients still experience varying degrees of long-term disabilities post-injury with consequent demands on carers and resources, and there is room for improvement. Biomarkers are a key aspect of neuromonitoring. A broad definition of a biomarker is any observable feature that can be used to inform on the state of the patient, e.g., a molecular species, a feature on a scan, or a monitoring characteristic, e.g., cerebrovascular pressure reactivity index. Biomarkers are usually quantitative measures, which can be utilized in diagnosis and monitoring of response to treatment. They are thus crucial to the development of therapies and may be utilized as surrogate endpoints in Phase II clinical trials. To date, there is no specific drug treatment for acute brain injury, and many seemingly promising agents emerging from pre-clinical animal models have failed in clinical trials. Large Phase III studies of clinical outcomes are costly, consuming time and resources. It is therefore important that adequate Phase II clinical studies with informative surrogate endpoints are performed employing appropriate biomarkers. In this article, we review some of the available systemic, local, and imaging biomarkers and technologies relevant in acute brain injury patients, and highlight gaps in the current state of knowledge.We gratefully acknowledge financial support as follows. Research support: the Medical Research Council (MRC, Grant Nos. G0600986 ID79068 and G1002277 ID98489) and the National Institute for Health Research Biomedical Research Centre (NIHR BRC) Cambridge (Neuroscience Theme; Brain Injury and Repair Theme). Authors’ support: Keri Linda H. Carpenter – NIHR BRC Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); Ibrahim Jalloh – MRC (Grant no. G1002277 ID 98489) and NIHR BRC Cambridge; Adel Helmy – MRC/Royal College of Surgeons of England Clinical Research Training Fellowship (Grant no. G0802251) and Raymond and Beverly Sackler Fellowship; Virginia F. J. Newcombe–Health Foundation/Academy of Medical Sciences Clinician Scientist Fellowship; Richard J. Shannon–NIHR BRC (Neuroscience Theme; Brain Injury and Repair Theme); Angelos G. Kolias–Royal College of Surgeons of England Research Fellowship, NIHR Academic Clinical Fellowship, and a Raymond and Beverly Sackler Studentship; David Krishna Menon–NIHR Senior Investigator Award; Peter J. Hutchinson – NIHR Research Professorship, Academy of Medical Sciences/Health Foundation Senior Surgical Scientist Fellowship.This is the final published version. It first appeared at http://journal.frontiersin.org/article/10.3389/fneur.2015.00026/full#h13

A Comparison of Oxidative Lactate Metabolism in Traumatically Injured Brain and Control Brain.

Metabolic abnormalities occur after traumatic brain injury (TBI). Glucose is conventionally regarded as the major energy substrate, although lactate can also be an energy source. We compared 3-13C lactate metabolism in TBI with "normal" control brain and muscle, measuring 13C-glutamine enrichment to assess tricarboxylic acid (TCA) cycle metabolism. Microdialysis catheters in brains of nine patients with severe TBI, five non-TBI brain surgical patients, and five resting muscle (non-TBI) patients were perfused (24 h in brain, 8 h in muscle) with 8 mmol/L sodium 3-13C lactate. Microdialysate analysis employed ISCUS and nuclear magnetic resonance. In TBI, with 3-13C lactate perfusion, microdialysate glucose concentration increased nonsignificantly (mean +11.9%, p = 0.463), with significant increases (p = 0.028) for lactate (+174%), pyruvate (+35.8%), and lactate/pyruvate ratio (+101.8%). Microdialysate 13C-glutamine fractional enrichments (median, interquartile range) were: for C4 5.1 (0-11.1) % in TBI and 5.7 (4.6-6.8) % in control brain, for C3 0 (0-5.0) % in TBI and 0 (0-0) % in control brain, and for C2 2.9 (0-5.7) % in TBI and 1.8 (0-3.4) % in control brain. 13C-enrichments were not statistically different between TBI and control brain, showing both metabolize 3-13C lactate via TCA cycle, in contrast to muscle. Several patients with TBI exhibited 13C-glutamine enrichment above the non-TBI control range, suggesting lactate oxidative metabolism as a TBI "emergency option."Medical Research Council (Grant Nos. G0600986 ID79068 and G1002277 ID98489) and National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme). Authors’ support: IJ – Medical Research Council (Grant no. G1002277 ID 98489) and National Institute for Health Research Biomedical Research Centre, Cambridge; KLHC – National Institute for Health Research Biomedical Research Centre, Cambridge (Neuroscience Theme; Brain Injury and Repair Theme); CG – the Canadian Institute of Health Research; AH – Medical Research Council/Royal College of Surgeons of England Clinical Research Training Fellowship (Grant no. G0802251) and Raymond and Beverly Sackler Fellowship; Royal College of Surgeons of England and the NIHR Cambridge Biomedical Research Centre; DKM and JDP – National Institute for Health Research Senior Investigator Awards; MPM - Medical Research Council UK (MC_U105663142) and a Wellcome Trust Investigator award (110159/Z/15/Z). PJH – National Institute for Health Research Professorship, Academy of Medical Sciences/Health Foundation Senior Surgical Scientist Fellowship and the National Institute for Health Research Biomedical Research Centre, Cambridge