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I Phillips

Publications and source records attributed to I Phillips.

At least 19 recordsLinked to original sources
PubMed2003

A prospective, comparative study of the para-aminobenzoic acid test and faecal elastase 1 in the assessment of exocrine pancreatic function.

BACKGROUND: The assessment of exocrine pancreatic insufficiency is part of the routine work-up of patients with persistent diarrhoea or suspected steatorrhoea. Direct and indirect tests for the diagnosis of exocrine pancreatic insufficiency have their drawbacks. Measurement of faecal elastase 1 by enzyme-linked immunoabsorbent assay is a simple, non-invasive, robust test for exocrine pancreatic insufficiency. METHODS: We performed a prospective comparison of the para-aminobenzoic acid test and faecal elastase 1 test in 45 patients being investigated for diarrhoea or suspected steatorrhoea. Details of clinical suspicion, imaging and response to treatment were recorded. RESULTS: Exocrine pancreatic function was normal in 20 patients with normal para-aminobenzoic acid and faecal elastase 1 levels. Eight patients had exocrine pancreatic insufficiency with low para-aminobenzoic acid and faecal elastase 1 levels, which improved with enzyme supplementation. In 14 of the 15 patients with low or borderline low para-aminobenzoic acid and normal faecal elastase 1 levels, a non-pancreatic cause was found; one patient had a false positive para-aminobenzoic acid test. Two had normal para-aminobenzoic acid but low faecal elastase 1 levels. One improved with pancreatic supplementation, and imaging revealed chronic pancreatitis. The other had a false positive faecal elastase 1 test related to profuse diarrhoea. CONCLUSIONS: Faecal elastase 1 estimation is a simple, non-invasive, robust test of exocrine pancreatic insufficiency, performed on an out-patient stool sample. Its diagnostic performance is superior to that of the para-aminobenzoic acid test in investigating patients with diarrhoea or suspected steatorrhoea.

4-Aminobenzoic Acid↗
PubMed2002

Erythromycin susceptibility of viridans streptococci from the normal throat flora of patients treated with azithromycin or clarithromycin.

OBJECTIVE: To study the emergence of macrolide resistance in throat flora following treatment with clarithromycin or azithromycin. METHODS: Throat samples were collected before and after treatment and plated as a lawn on Columbia blood agar with an erythromycin E test strip. Minimum inhibitory concentrations (MICs) of erythromycin, clarithromycin and azithromycin were determined against isolates of distinct morphology with erythromycin E test MIC results equal to or greater than 2 mg/L. Polymerase chain reaction techniques were used to determine the genetic mechanisms of resistance. RESULTS: There were 749 resistant isolates of which 474 (63%) were streptococci. Only a quarter of the patients had no resistant streptococci before treatment started. There were increases in the numbers of resistant isolates and in the number of patients carrying a resistant flora during and after treatment. The most common genes identified were mefA/E in isolates with low-level resistance and ermA/M in isolates with high-level resistance. CONCLUSIONS: There is a pool of streptococci carrying genes associated with macrolide resistance in the normal respiratory flora of generally healthy adults. Differences between the patients treated with clarithromycin and those treated with azithromycin were difficult to assess because of the large number of patients in each group with macrolide-resistant streptococci before treatment. Although there were some differences these were not statistically significant.

Anti-Bacterial Agents↗
PubMed2001

Synergistic neutralizing antibody response to a dengue virus type 2 DNA vaccine by incorporation of lysosome-associated membrane protein sequences and use of plasmid expressing GM-CSF.

We have previously shown that a dengue virus type 1 DNA vaccine expressing premembrane (prM) and envelope (E) genes was immunogenic in mice and monkeys and that rhesus monkeys vaccinated with this construct were completely to partially protected from virus challenge. In order to improve the immunogenicity of dengue DNA vaccines, we have evaluated the effect of lysosome targeting of antigens and coimmunization with a plasmid expressing GM-CSF on antibody responses. A dengue virus type 2 candidate vaccine containing prM and E genes was constructed in which the transmembrane and cytoplasmic regions of E were replaced by those of the lysosome-associated membrane protein (LAMP). The modified vaccine construct expressed antigen that was colocalized with endogenous LAMP in lysosomal vesicles of transfected cells, whereas the antigen expressed from the unmodified construct was not. It was hypothesized that targeting of antigen to the lysosomal compartment will increase antigen presentation by MHC class II, leading to stronger CD4-mediated immune responses. Mice immunized with the modified construct responded with significantly higher levels of virus neutralizing antibodies compared to those immunized with the unmodified construct. Coimmunization of mice with a plasmid expressing murine GM-CSF enhanced the antibody response obtained with either the unmodified or the modified construct alone. The highest antibody responses were noted when the modified construct was coinjected with plasmid expressing the GM-CSF gene. These results could form the basis for an effective tetravalent dengue virus DNA vaccine.

3T3 Cells↗
PubMed2001

Prudent use of antibiotics: are our expectations justified?

Prudent use of antibiotics has 3 components, rational use, adherence to local guidelines and policies, and avoidance or reversal of upward demographic trends in antibiotic resistance. Although rational use is mandatory, it must be recognized that adherence to policies will reduce clinical freedom, for good or ill. Expectations that prudent use will deliver reversals in resistance trends should be accepted with caution. Sound, pertinent data are lacking, and our ability to detect change, if it does occur, and to attribute its cause correctly, is questionable.

Animals↗
PubMed2001

Reevaluation of antibiotic breakpoints.

Differences in antibiotic breakpoints have resulted from differences in clinical practice and in interpretation of the parameters that are considered when breakpoints are set. Differences in the first of these are less common for newer agents, whereas differences in the latter could be resolved by consensus discussions. Greater difficulty arises when common pathogens acquire resistance, especially when this occurs by degrees, as has happened with penicillin for gonococci and the pneumococci, and for the fluoroquinolones in relation to a wide variety of bacterial species. Changes to breakpoints under such circumstances should be introduced only after the most careful consideration and the education of diagnostic microbiologists and clinicians.

Anti-Bacterial Agents↗
PubMed2001

Surveillance of antimicrobial resistance--what, how and whither?

OBJECTIVE: To express the views of a working party held to consider antibiotic resistance surveillance systems, their strengths and weaknesses, and their current and future applications. METHODS: The participants, all of whom were experienced in this field, discussed the development of surveillance systems in relation to the increasing prevalence of resistance to antibacterial agents and the current interest in surveillance systems shown by many official bodies, in both the human and veterinary fields. The problems inherent in surveillance systems were considered together with the applications of different systems. RESULTS: The properties of good antibiotic resistance surveillance systems were defined. Surveillance systems vary widely from those with a narrow base, focusing on few organisms in one disease area, to those covering many diseases, many organisms (including normal flora) and many compounds. Whatever their design, they should be able to detect significant differences and shifts in susceptibility to various antibacterial agents, and the information derived from them should reach as many interested parties as possible in a timely manner. In using this information to decide strategies, criteria for action need to be determined by pragmatic consensus. Funding remains a major problem, with few large studies being supported by official bodies in spite of their professed enthusiasm for surveillance. In consequence, many current systems are funded by the pharmaceutical industry and are of necessity restricted in their focus. CONCLUSIONS: Antibiotic resistance surveillance studies should and can be well planned and well executed. Many current systems suffer from well-recognized but uncorrected biases. Consortium funding will be necessary for large schemes to be successful. There is no "ideal" surveillance system.

Animals↗
PubMed2001

The in vitro activity of daptomycin against 514 Gram-positive aerobic clinical isolates.

The in vitro activity of daptomycin was assessed in comparison with that of vancomycin and penicillin against a wide range of Gram-positive aerobic clinical isolates. MICs were determined by an agar dilution method on Mueller-Hinton agar (NCCLS/EUCAST) and on Isotonic agar adjusted to contain 50 mg/L free calcium (BSAC). Both media were enriched with 5% horse blood for fastidious organisms. Daptomycin MICs for all 172 staphylococci, including methicillin-susceptible and methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus haemolyticus, were 0.03-0.5 mg/L. For 99 of the 100 enterococci (Enterococcus faecalis, n = 50; Enterococcus faecium, n = 50), including 37 vancomycin-resistant isolates, they were 0.25-2 mg/L. For all 108 beta-haemolytic streptococci, including Streptococcus pyogenes and Streptococcus agalactiae, daptomycin MICs were 0.016- 0.25 mg/L; for 101 alpha-haemolytic streptococci, including Streptococcus pneumoniae and 'viridans' streptococci, they were 0.016-2 mg/L. For miscellaneous vancomycin-resistant isolates including Lactobacillus spp., Lactococcus spp., Leuconostoc spp., Pediococcus spp. and isolates of Enterococcus casseliflavus and Enterococcus gallinarum, daptomycin MICs were 0.03-2 mg/L; MICs for the seven isolates of Listeria monocytogenes were 0.25-4 mg/L. There was little difference between the results on Mueller-Hinton agar and on supplemented Isotonic agar The discrepant results occasionally obtained tended to be one dilution higher on supplemented Isotonic agar. Daptomycin was active (MICs < or = 2 mg/L) against all the isolates tested with the exception of one isolate each of E. faecium and L. monocytogenes (MICs = 4 mg/L). Our results indicate that daptomycin MICs are independent of methicillin and vancomycin MICs.

Anti-Bacterial Agents↗
PubMed2000

Immunogenicity of dengue virus type 1 DNA vaccines expressing truncated and full length envelope protein.

Recombinant plasmid DNA constructs expressing truncated or full-length dengue-1 envelope (E) with or without the pre-membrane (prM) were tested for immunogenicity in mice, as candidate dengue DNA vaccines. Two plasmids, one expressing the N-terminal 80% E and the other expressing prM and full length E were immunogenic in intradermally inoculated mice. The vaccinated mice produced dengue-1 specific antibodies that were both neutralizing and long lasting. Data suggested that the plasmid expressing prM and full length E produced virus like particles in transfected cells, and is probably a better immunogen compared to that expressing 80% E.

Animals↗
PubMed2000

Comparative in vitro activity of gemifloxacin.

Gemifloxacin is a new quinolone and, like moxifloxacin, trovafloxacin, grepafloxacin and clinafloxacin, is more potent in vitro than ciprofloxacin or ofloxacin against Gram-positive aerobes. Gemifloxacin was the most potent of the quinolones tested against streptococci and most ciprofloxacin-resistant pneumococci were susceptible to gemifloxacin. Gemifloxacin, like moxifloxacin, trovafloxacin, grepafloxacin and clinafloxacin, was more potent than ciprofloxacin or ofloxacin against all staphylococci and many ciprofloxacin-resistant isolates were susceptible to these quinolones. Against Gram-negative aerobes gemifloxacin was as potent as or slightly less potent than ciprofloxacin, and isolates resistant to ciprofloxacin were also resistant to gemifloxacin and to moxifloxacin, trovafloxacin and grepafloxacin. Gemifloxacin was also the most potent quinolone against Gram-positive anaerobes and fusobacteria but trovafloxacin was the most potent agent tested against other Gram-negative anaerobes.

Anti-Infective Agents↗
PubMed2000

Comparison of cation-adjusted Mueller-Hinton broth with Iso-Sensitest broth for the NCCLS broth microdilution method.

Comparison of MIC results obtained in different parts of the world is currently difficult because of variations in methods. In this study, cation-adjusted Mueller-Hinton broth, the NCCLS-recommended medium, was compared with Iso-Sensitest broth, which is widely used in Europe. Microbroth dilution testing, using the NCCLS procedure, was performed on 124 Gram-positive (staphylococci and enterococci) and Gram-negative (Enterobacteriaceae and Pseudomonas aeruginosa) isolates from the CDC reference set, with the only variable being the medium used. Twelve antimicrobial agents were tested: amoxycillin-clavulanic acid, ampicillin, ciprofloxacin, erythromycin, gentamicin, imipenem, levofloxacin, oxacillin, gemifloxacin, trimethoprim- sulphamethoxazole, tetracycline and vancomycin. Vancomycin, erythromycin and oxacillin were only evaluated for the Gram-positive organisms. Trimethoprim-sulphamethoxazole was only evaluated for a subset of Gram-negative organisms because of off-scale results. The 124 isolates were tested in one American and one UK laboratory with two batches of cation-adjusted Mueller-Hinton broth and two of Iso-Sensitest broth. A statistical evaluation of the data used a 24 fully specified factorial analysis to determine if there were significant differences in results owing to Gram reaction, site of testing and type and/or batch of broth. In addition, the cumulative results for each antimicrobial agent in each broth were plotted against the range of MIC dilutions tested. MICs of ciprofloxacin, levofloxacin, gemifloxacin, gentamicin and tetracycline were slightly higher (half a doubling dilution) with Iso-Sensitest broth than with Mueller-Hinton broth. MIC results for the other antimicrobial agents were equivalent. Essential and category agreement rates were comparable for all agents (88.4-100% and 88.2-99.0%, respectively).

Anti-Bacterial Agents↗
PubMed2000

Dengue virus type 1 DNA vaccine induces protective immune responses in rhesus macaques.

A candidate DNA vaccine expressing dengue virus type 1 pre-membrane and envelope proteins was used to immunize rhesus macaques. Monkeys were immunized intramuscularly (i.m.) or intradermally (i.d.) by three or four 1 mg doses of vaccine, respectively. Monkeys that were inoculated i.m. seroconverted more quickly and had higher antibody levels than those that were inoculated i.d. The sera exhibited virus-neutralizing activity, which declined over time. Four of the eight i.m.-inoculated monkeys were protected completely from developing viraemia when challenged 4 months after the last dose with homologous dengue virus. The other four monkeys had reduced viraemia compared with the control immunized monkeys. The i.d. -inoculated monkeys showed no reduction in viraemia when challenged with the virus. All vaccinated monkeys showed an anamnestic antibody response, indicating that they had established immunological memory. Vaccine-induced antibody had an avidity index similar to that of antibody induced by virus infection; however, no clear correlation was apparent between antibody avidity and virus neutralization titres.

Animals↗