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1.  Development of a Native Escherichia coli Induction System for Ionic Liquid Tolerance 
PLoS ONE  2014;9(7):e101115.
The ability to solubilize lignocellulose makes certain ionic liquids (ILs) very effective reagents for pretreating biomass prior to its saccharification for biofuel fermentation. However, residual IL in the aqueous sugar solution can inhibit the growth and function of biofuel-producing microorganisms. In E. coli this toxicity can be partially overcome by the heterologous expression of an IL efflux pump encoded by eilA from Enterobacter lignolyticus. In the present work, we used microarray analysis to identify native E. coli IL-inducible promoters and develop control systems for regulating eilA gene expression. Three candidate promoters, PmarR’, PydfO’, and PydfA’, were selected and compared to the IPTG-inducible PlacUV5 system for controlling expression of eilA. The PydfA’ and PmarR’ based systems are as effective as PlacUV5 in their ability to rescue E. coli from typically toxic levels of IL, thereby eliminating the need to use an IPTG-based system for such tolerance engineering. We present a mechanistic model indicating that inducible control systems reduce target gene expression when IL levels are low. Selected-reaction monitoring mass spectrometry analysis revealed that at high IL concentrations EilA protein levels were significantly elevated under the control of PydfA’ and PmarR’ in comparison to the other promoters. Further, in a pooled culture competition designed to determine fitness, the strain containing pPmarR’-eilA outcompeted strains with other promoter constructs, most significantly at IL concentrations above 150 mM. These results indicate that native promoters such as PmarR’ can provide effective systems for regulating the expression of heterologous genes in host engineering and simplify the development of industrially useful strains.
PMCID: PMC4077768  PMID: 24983352
2.  Design and Synthesis of a Stable Oxidized Phospholipid Mimic with Specific Binding Recognition for Macrophage Scavenger Receptors 
Journal of medicinal chemistry  2012;55(18):8178-8182.
Macrophage scavenger receptors appear to play a major role in the clearance of oxidized phospholipid (OxPL) products. Discrete peptide-phospholipid conjugates with the phosphatidylcholine head group have been shown to exhibit binding affinity for these receptors. We report the preparation of a water soluble, stable peptide-phospholipid conjugate (9) that possesses the necessary physical properties to enable more detailed study of the role(s) of OxPL in metabolic disease.
PMCID: PMC3465084  PMID: 22934615
3.  Characterization of Oxidized Phosphatidylethanolamine Derived from RAW 264.7 Cells using 4-(Dimethylamino)benzoic Acid Derivatives 
Recently, a derivative of phosphatidylethanolamine (PE), namely the 4-(dimethylamino)benzoic acid derivative has been developed with various isotope labeled variants that provided a universal precursor ion scan for diacyl, ether, and plasmalogen PE lipids that can not be accomplished otherwise. This derivative was further investigated as a means to facilitate characterization of various oxidized phosphatidylethanolamine lipids by collision activation. Phospholipids derived from RAW 264.7 cells were treated with a free radical generating system to generate a complex mixture of oxidized and nonoxidized lipids that were separated by reversed phase HPLC and detected using a precursors of m/z 191 scan for the d0-DMABA labeled control sample and a precursors of m/z 197 scan for the d6-DMABA labeled oxidized sample. Collisional activation of the corresponding [M-H]− ions permitted the identification of several chained shortened ω-aldehydes, as well as direct oxygen addition products including isoprostane PE and monohydroxy PE oxidized phospholipids that were not easily detected without the use of the DMABA derivatives. The stable isotope labeled derivatives permitted assessment of relative quantitative changes in oxidized lipids based upon ion abundance.
PMCID: PMC3086548  PMID: 20530831
electrospray; tandem mass spectrometry; lipid oxidation; derivatization
4.  Stable Isotope Labeled 4-(Dimethylamino)benzoic Acid Derivatives of Glycerophosphoethanolamine Lipids 
Analytical chemistry  2009;81(16):6633-6640.
A set of four (d0, d4, d6, and d10) deuterium enriched 4-(dimethylamino)benzoic acid (DMABA) N-hydroxysuccinimide (NHS) ester reagents was developed that react with the primary amine group of glycerophosphoethanolamine (PE) lipids to create derivatives where all subclasses of DMABA labeled PE are detected by a common precursor ion scan. The positive ion collision induced dissociation data from (d0, d4, d6, and d10)-DMABA labeled PE standards indicated that a precursor ion scan of m/z 191.1, 195.1, 197.1, and 201.1 could be used to selectively detect (d0, d4, d6, and d10)-DMABA modified PE, respectively, in a complex biological mixture. The PE lipids from a time course (0, 30, 60, and 300 min) of AAPH treatment of liposomes made of RAW 264.7 cell phospholipids were each labeled with the d0-, d4-, d10-, and d6-DMABA NHS ester reagents, respectively. The DMABA derivatives revealed loss of endogenous PE lipids and an increase in oxidized PE lipid throughout the time course of AAPH treatment. These DMABA NHS ester reagents provide a universal scan for diacyl, ether, and plasmalogen PE lipids that can not be readily observed otherwise, enable differential labeling, and provide an internal standard for each PE lipid.
PMCID: PMC2929906  PMID: 20337376
electrospray; tandem mass spectrometry; lipid oxidation; derivatization
5.  Human hepatic stem cells from fetal and postnatal donors 
The Journal of Experimental Medicine  2007;204(8):1973-1987.
Human hepatic stem cells (hHpSCs), which are pluripotent precursors of hepatoblasts and thence of hepatocytic and biliary epithelia, are located in ductal plates in fetal livers and in Canals of Hering in adult livers. They can be isolated by immunoselection for epithelial cell adhesion molecule–positive (EpCAM+) cells, and they constitute ∼0.5–2.5% of liver parenchyma of all donor ages. The self-renewal capacity of hHpSCs is indicated by phenotypic stability after expansion for >150 population doublings in a serum-free, defined medium and with a doubling time of ∼36 h. Survival and proliferation of hHpSCs require paracrine signaling by hepatic stellate cells and/or angioblasts that coisolate with them. The hHpSCs are ∼9 μm in diameter, express cytokeratins 8, 18, and 19, CD133/1, telomerase, CD44H, claudin 3, and albumin (weakly). They are negative for α-fetoprotein (AFP), intercellular adhesion molecule (ICAM) 1, and for markers of adult liver cells (cytochrome P450s), hemopoietic cells (CD45), and mesenchymal cells (vascular endothelial growth factor receptor and desmin). If transferred to STO feeders, hHpSCs give rise to hepatoblasts, which are recognizable by cordlike colony morphology and up-regulation of AFP, P4503A7, and ICAM1. Transplantation of freshly isolated EpCAM+ cells or of hHpSCs expanded in culture into NOD/SCID mice results in mature liver tissue expressing human-specific proteins. The hHpSCs are candidates for liver cell therapies.
PMCID: PMC2118675  PMID: 17664288
6.  The challenges of joint working: lessons from the Supporting People Health Pilot evaluation 
This paper reports the findings of the evaluation of the Supporting People Health Pilots programme, which was established to demonstrate the policy links between housing support services and health and social care services by encouraging the development of integrated services. The paper highlights the challenges of working across housing, health and social care boundaries.
The evaluation of the six health pilots rested on two main sources of data collection: Quarterly Project Evaluation Reports collected process data as well as reporting progress against aims and objectives. Semi-structured interviews—conducted across all key professional stakeholder groups and agencies and with people who used services—explored their experiences of these new services.
The ability of pilots to work across organisational boundaries to achieve their aims and objectives was associated not only with agencies sharing an understanding of the purpose of the joint venture, a history of joint working and clear and efficient governance arrangements but on two other characteristics: the extent and nature of statutory sector participation and, whether or not the service is defined by a history of voluntary sector involvement. In particular the pilots demonstrated how voluntary sector agencies appeared to be less constrained by organisational priorities and professional agenda and more able to respond flexibly to meet the complex needs of individuals.
Conclusion and discussion
The pilots demonstrate that integrating services to support people with complex needs works best when the service is determined by the characteristics of those who use the service rather than pre-existing organisational structures.
PMCID: PMC2092398  PMID: 18043723
governance; housing support; joint working
8.  DNA Replication Efficiency Depends on Transcription Factor-Binding Sites 
Journal of Virology  2001;75(12):5638-5645.
Naturally arising variants of simian virus 40 (SV40), generated by serial passage of the virus at high multiplicities of infection, provide important insight into the role of transcription factor-binding sites in enhancing DNA replication. Although the variants that arise from numerous recombination events are the result of selective pressure to replicate more efficiently than the other variants in the infection, there is no transcription pressure. Therefore, it is interesting that a minimum of two viral Sp1 transcription factor-binding sites are retained and that host AP-1 and NF-1 transcription factor-binding sites are incorporated into the 100-bp regulatory region that maximizes DNA replication in these variants. We cotransfected COS-1 cells (that provide viral large T antigen for DNA replication) to examine the effect of transcription factor-binding sites on the replication of plasmid constructs that contain the SV40 origin of replication (ori). The level of relative replication efficiency (RRE) depends on the number and type of transcription factor-binding sites. Replication increases as the number of transcription factor-binding sites increases within the regulatory region of the variants; AP-1 sites are more effective than NF-1 transcription factor-binding sites. Competition between constructs in transfections magnifies the difference in their RREs. The results indicate that transcription factor-binding sites play an important role in enhancing DNA replication.
PMCID: PMC114276  PMID: 11356971
9.  Urologic Complication of Laparoscopic Appendectomy 
Abscess formation after a ruptured appendix is a well-known phenomenon. Extra-abdominal complications are somewhat rare. Here we present an unusual urologic complication in a case of a perforated appendix and abdominal sepsis.
PMCID: PMC3015409  PMID: 11304001
Laparoscopy; Urology; Laparoscopic appendectomy; Scrotal abscess
10.  Photoaffinity Analog of the Semisynthetic Echinocandin LY303366: Identification of Echinocandin Targets in Candida albicans 
The echinocandins are a family of cyclic lipopeptides with potent antifungal activity. These compounds inhibit the synthesis of β-1,3-glucan in fungi. The new semisynthetic echinocandin LY303366 was derivatized to produce a photoactivatable cross-linking echinocandin analog with antifungal activity. This analog was radioiodinated and used as a probe in microsomal membrane preparations of Candida albicans which contain glucan synthase activity. The photoaffinity probe identified two major proteins of 40 and 18 kDa in both membrane preparations. Labeling of these proteins was specific in that it required irradiation with UV light and was effectively competed against with unlabeled echinocandin analogs. In addition, the abilities of echinocandin analogs to compete with the photoaffinity probe correlated to their relative antifungal potencies and glucan synthase inhibition. The 40-kDa protein was isolated, and partial sequences were obtained from internal peptide fragments of the protein. Analysis of the sequences of these internal peptides of the 40-kDa protein revealed that it was a new protein not previously described as being involved in glucan synthesis or the mode of action of echinocandins.
PMCID: PMC105773  PMID: 9593148
12.  The Acute Abdomen* 
Postgraduate Medical Journal  1936;12(124):45-52.
PMCID: PMC2476715  PMID: 21312994
PMCID: PMC1068439  PMID: 21611226
15.  Original Papers 
PMCID: PMC1068100  PMID: 21611503
18.  Sarcoma of the Right Tonsil 
Proceedings of the Royal Society of Medicine  1913;6(Laryngol Sect):124-126.
PMCID: PMC2006616  PMID: 19976835
19.  Note on the Ætiology of Leprosy 2 
Proceedings of the Royal Society of Medicine  1912;5(Dermatol Sect):17-20.
PMCID: PMC2005915  PMID: 19975758
21.  The Morison Lectures ON EPILEPSY 
British Medical Journal  1910;1(2570):803-807.
PMCID: PMC2331010  PMID: 20765008
22.  The Morison Lectures ON EPILEPSY 
British Medical Journal  1910;1(2571):866-871.
PMCID: PMC2331273  PMID: 20765021
23.  The Morison Lectures ON EPILEPSY 
British Medical Journal  1910;1(2569):733-737.
PMCID: PMC2331220  PMID: 20764986

Results 1-25 (32)