Browsing by Author "Stapleton, P."
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item Does the United Kingdom’s Local Improvement Finance Trust (LIFT) Scheme for Primary Health Care Enhance Partnership Working?(Public Works Management & Policy, 2020-01-20) Agyenim-Boateng, C.; Stafford, A.; Stapleton, P.This article draws on a qualitative case study comparing two U.K. primary health care schemes which were entered into as part of the Local Improvement Finance Trust (LIFT) policy. LIFT takes the form of a social infrastructure Public Private Partnership (PPP) where public procurers and private suppliers work together in active long-term partnering agreements to deliver local primary health care facilities. The organizational structure is that of a joint venture company which is jointly owned by public and private partners, with the expectation that by having both the public and private sector represented on the company board partnership working between the two sectors is enhanced. The two schemes studied delivered contrasting results. One scheme showed how the private sector dominated the board, making partnership working difficult to achieve in the context of directors following their fiduciary role to maximize profits for shareholders. However, the findings from the second scheme showed that partnership working and LIFT success may be dependent on trust, general business ethos, and key personalities working together. Policy makers should therefore pay attention to not only the organizational structures, but also how the private sector controls and governance are exercised to benefit all stakeholders.Item Growth assessment of mixed cultures of probiotics and common pathogens(Anaerobe, 2023) Fredua-Agyeman, M.; Stapleton, P.; Gaisford, S.Objectives: In this work, an isothermal microcalorimeter was applied to investigate the antipathogenic activity of three probiotics (Lactobacillus acidophilus, Bifidobacterium lactis and Bifidobacterium bifidum) against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli using the probiotics in mixed culture with the pathogenic microorganisms. Methods: A microcalorimeter was used to monitor the growth of the microorganisms as pure cultures and as co cultures at 37 ◦C. Relative growths of the probiotics and pathogenic species were determined after microcalo rimetric measurements by serial dilution and plate incubation. Relative growth of mixed cultures of E. coli with L. acidophilus or B. lactis was also determined by traditional plate growth assay for 5.5 h. Results: The results showed growth profiles of the microorganisms that were characteristic and showed different lag and peak times for the species. The pathogenic species grew faster than the probiotic species. In the co cultures, the growth profile of both pathogenic species and probiotics could be identified with the microcalo rimeter. Although the pathogenic species grew faster, at the end of the assay, the results showed that the pathogenic species were inhibited in growth by the probiotics as no viable growth of the pathogenic species was detected whereas 107 –108 CFU/mL of the probiotics were enumerated after the microcalorimetric assay. Using the traditional plate assay, the data confirmed co-growth of the probiotics and E. coli although cell numbers of E. coli were higher than the probiotics during 5.5 h of co-culture incubation when both were inoculated at 106 CFU/mL. Conclusion: The results demonstrate the antipathogenic effects of probiotics and highlights the potential of microcalorimetry in live mixed culture assays and its limitation.Item Inhibiting plasmid mobility: The effect of isothiocyanates on bacterial conjugation(International Journal of Antimicrobial Agents, 2019-05) Kwapong, A.A.; Stapleton, P.; Gibbons, S.Bacterial conjugation is the main mechanism for the transfer of multiple antimicrobial resistance genes among pathogenic micro-organisms. This process may be controlled by compounds that inhibit bacterial conjugation. In this study, the effects of allyl isothiocyanate, l-sulforaphane, benzyl isothiocyanate, phenylethyl isothiocyanate and 4-methoxyphenyl isothiocyanate on the conjugation of broad-host-range plasmids harbouring various antimicrobial resistance genes in Escherichia coli were investigated, namely plasmids pKM101 (IncN), TP114 (IncI2), pUB307 (IncP) and the low-copy-number plasmid R7K (IncW). Benzyl isothiocyanate (32 mg/L) significantly reduced conjugal transfer of pKM101, TP114 and pUB307 to 0.3 ± 0.6%, 10.7 ± 3.3% and 6.5 ± 1.0%, respectively. l-sulforaphane (16 mg/L; transfer frequency 21.5 ± 5.1%) and 4-methoxyphenyl isothiocyanate (100 mg/L; transfer frequency 5.2 ± 2.8%) were the only compounds showing anti-conjugal specificity by actively reducing the transfer of R7K and pUB307, respectively.Item A new dimeric imidazole alkaloid plasmid conjugation inhibitor from Lepidium sativum(Elsevier Ltd, 2018-05) Kwapong, A.A.; Stapleton, P.; Gibbons, S.Phytochemical investigation of the methanolic extract of Lepidium sativum seeds led to the isolation of a new compound, named 2-(3-(3-((1H-imidazol-2-yl)methyl)-5-methoxyphenoxy)benzyl)-1H-imidazole and given the trivial name Lepidine AK (1), along with three known compounds; Lepidine E (2), Lepidine B (3) and 2-(3-(2-((1H-imidazol-2-yl)methyl)-6-methoxyphenoxy)benzyl)-1H-imidazole (4). The structures were elucidated based on NMR spectroscopy, UV, IR and high-resolution electrospray ionization mass spectrometry. The isolated compounds were tested for bacterial conjugation inhibition. Lepidine AK (1, 100 μg/mL) reduced the conjugal transfer of the IncI2 plasmid TP114 to 44.7 ± 3.5% but interestingly promoted the conjugation of the IncN plasmid pKM101 to greater than 120%. © 2018