Search PubMed⌕ Search

Biomedical subjects

I Phillips

Publications and source records attributed to I Phillips.

At least 181 records · Page 10Linked to original sources
PubMed1986

Serotonin and 5-hydroxyindoleacetic acid in brains of suicide victims. Comparison in chronic schizophrenic patients with suicide as cause of death.

Serotonin (5-HT) and 5-hydroxyindoleacetic acid concentrations were determined in various brain areas of nonschizophrenic suicide victims, chronic schizophrenic patients with or without suicide as the cause of death, and normal control subjects without psychiatric or neurologic disorders. Serotonin concentrations in the basal ganglia were significantly elevated in suicide victims and chronic schizophrenic patients, as were 5-hydroxyindoleacetic acid concentrations in the occipital cortex. These differences were not specific to either patient group and may have been caused by neuroleptic or antidepressant treatment. A decreased 5-HT concentration was found in the hypothalamus of nonschizophrenic suicide victims. Among the chronic schizophrenic patients, there was no significant difference in the hypothalamic 5-HT content between the suicide victims and others, indicating that low 5-HT levels in the hypothalamus are not characteristic of schizophrenic patients who died of suicide.

Adolescent↗
PubMed1986

Strategies for typing and properties of epidemic methicillin-resistant Staphylococcus aureus.

Isolates of 17 strains of epidemic methicillin-resistant Staphylococcus aureus from outbreaks in ten hospitals in the UK were investigated with a variety of techniques both to explore their properties and to type them in order to confirm or refute known or suspected epidemiology. The techniques consisted of a biotyping system, peptidoglycan analysis, testing of antibiotic sensitivity to 21 agents, various phage-typing methods including heat shock, plasmid pattern analysis, and heat cure derivation of plasmid-less isogenic strains. All strains resembled those originally isolated in Australia, being in the possession of a large number of chromosomal resistance factors, pigmentation, ability to produce lipase and large molecular weight plasmids (c.15 Md to c.23 Md) which conferred resistance to gentamicin, propamidine, ethidium bromide, cetrimide and chlorhexidine. Some strains also had a c.3 Md plasmid conferring chloramphenicol resistance and others a c.1 Md cryptic plasmid. A large percentage of the population was resistant to 25 mg/l methicillin at 37 degrees C, an unusual feature. All the strategies, with the exception of peptidoglycan analysis, contributed to typing of the strains.

Bacteriophage Typing↗
PubMed1986

An outbreak of Serratia marcescens transmitted by contaminated breast pumps in a special care baby unit.

Laboratory surveillance of clinical isolates for Serratia spp. revealed a sudden increase from babies in the Special Care Baby Unit (SCBU). It was established that breast-milk pumps on the post-natal wards were being disinfected inadequately, resulting in contamination of milk and cross-infection within the SCBU. Thirty babies were colonized and no deaths were attributable to the organism. Rectal carriage by the babies was common and often prolonged. The outbreak was brought under control when the method of disinfection of the pumps was changed from soaking in hypochlorite solution to washing at 80 degrees C.

Bacterial Infections↗
PubMed1986

Beta-lactamases with high activity against imipenem and Sch 34343 from Aeromonas hydrophila.

Two groups of inducible beta-lactamases were found among nine isolates of Aeromonas hydrophila. Five isolates produced enzymes with high activity against the penem Sch 34343 and the carbapenem imipenem: the enzymes from some of these isolates also had activity against penicillin, ampicillin, carbenicillin, cephaloridine and cephalexin but one isolate produced an enzyme with no detectable activity against cephalosporins. The other four isolates produced typical 'cephalosporinases' with activity against cephaloridine and cephalexin but not against cefuroxime, cefotaxime, penicillins, imipenem or Sch 34343.

Aeromonas↗
PubMed1986

A comparison of the homogeneous enzyme immunoassay (EMIT) autocarousel and quantitative single test (QST) systems with the radioenzymatic assay.

A comparison was made of three methods for gentamicin assay; a modification of the radioenzymatic transferase technique, which was used as the reference method; EMIT autocarousel; and EMIT quantitative single test (QST). Correlation of both EMIT systems with the radioenzymatic method and with each other gave acceptable correlation coefficients, 0.955-0.975, for the range of concentrations tested. The coefficients of variation for within assay studies were between 3.3 and 4.9 for all three methods. Both EMIT systems provided rapid results, within minutes, albeit at a higher cost than the radioenzymatic assay. The radioenzymatic technique although cheaper with regard to the cost of materials involves considerably more technical time and effort and might not be considered suitable for samples received out-of-hours. However the combination of both EMIT systems provides facilities for batch and one-off sample tests and the ease of operation and rapid results are suited to out-of-hours operation.

Costs and Cost Analysis↗
PubMed1986

Macrolide, lincosamide and streptogramin resistance in Campylobacter jejuni/coli.

Strains of erythromycin-resistant Campylobacter jejuni/coli isolated in the United Kingdom, Canada and Europe, were also resistant to tylosin, spiramycin and clindamycin and, like sensitive strains, were insensitive to virginiamycin and pristinamycin component B. These were designated as macrolide-lincosamide-streptogramin generalized resistant organisms and macrolide-lincosamide generalized resistant on the basis of patterns of resistance to pristinamycin components A and B. Two erythromycin-sensitive strains whose resistance to spiramycin and tylosin had been produced in the laboratory showed cross resistance to erythromycin, but were still sensitive to clindamycin. These were characterized as macrolide-streptogramin A inducible resistant organisms. The isolates tested were identified and all were found to be C. coli, except for two strains, one erythromycin-resistant and one erythromycin-sensitive, which hydrolyzed hippurate and were thus identified as C. jejuni.

Anti-Bacterial Agents↗
PubMed1986

The comparative in-vitro activity of pefloxacin.

The in-vitro antibacterial activities of pefloxacin, other 4-quinolones and representative beta-lactams and aminoglycosides were assessed by determination of minimum inhibitory concentrations (MICs). Pefloxacin (MICs mostly 0.03-2 mg/l) was highly active against Enterobacteriaceae. Gentamicin had slightly lower activity, and ceftazidime and norfloxacin similar activities to pefloxacin whereas ciprofloxacin was more active. Pefloxacin (MICs 0.03-2 mg/l) was active against Acinetobacter but again ciprofloxacin was more active. Aeromonas was highly susceptible to pefloxacin and norfloxacin (MICs 0.008-0.03 mg/l) as well as to ciprofloxacin (MICs 0.001-0.008 mg/l). Pefloxacin (MICs 1-8 mg/l) had similar activities to ceftazidime and gentamicin against Pseudomonas aeruginosa but tobramycin (MICs 0.25-32 mg/l), norfloxacin (MICs 0.25-4 mg/l) and ciprofloxacin (MICs 0.06-1 mg/l) were generally more active. Haemophilus influenzae was susceptible to pefloxacin (MICs 0.008-0.06 mg/l) and to norfloxacin and ciprofloxacin, all of which were more active than ampicillin or ceftazidime. Gardnerella vaginalis was not very susceptible to pefloxacin (MICs 2-8 mg/l), the other 4-quinolones or gentamicin but ampicillin and ceftazidime were highly active. Neisseria gonorrhoeae was very susceptible to pefloxacin and norfloxacin (MICs 0.016-0.12 mg/l) and ciprofloxacin (MICs 0.002-0.008 mg/l). The activity of pefloxacin (MICs 0.25-1 mg/l) was similar to that of ciprofloxacin (MICs 0.12-2 mg/l) but greater than that of norfloxacin (MICs 0.5-4 mg/l) against Staphylococcus aureus. Vancomycin (MICs 1-2 mg/l) had similar activity in vitro but whilst gentamicin was highly active against some isolates, others were resistant. Pefloxacin (MICs mostly 4-32 mg/l) and the other 4-quinolones had lower activity against streptococci (including alpha-, beta-, and non-haemolytic strains, enterococci and pneumococci) than against staphylococci. Benzylpenicillin (or ampicillin in the case of enterococci) were usually more active than any of the 4-quinolones. Bacteroides species, both of the fragilis and melaninogenicus/oralis groups were generally moderately resistant to pefloxacin (MICs 2-32 mg/l) and norfloxacin though ciprofloxacin was more active. Whilst the activity of pefloxacin and the other 4-quinolones was generally somewhat higher against the other anaerobes, ampicillin generally had greater activity.

Acinetobacter↗
PubMed1986

The in-vitro activity of CI-934 compared with that of other new 4-quinolones and nalidixic acid.

The in-vitro activity of CI-934, a new 4-quinolone compound, was compared with that of the other new 4-quinolones, enoxacin and ciprofloxacin, and also with that of nalidixic acid. CI-934 was more active than any of the other 4-quinolones tested against Gram-positive aerobic organisms including Staphylococcus aureus (MICs 0.06-0.25 mg/l), beta-haemolytic streptococci (MICs 0.12-0.5 mg/l), Streptococcus pneumoniae (MICs 0.25-0.5 ml/l), viridans streptococci (MICs 0.06-0.5 mg/l) and most enterococci (MICs 0.12-0.5 mg/l), although some ampicillin-resistant isolates of Str. faecium were slightly less susceptible (MICs 2 mg/l). All three of the newer 4-quinolones tested were highly active against Enterobacteriaceae, Aeromonas sp., Haemophilus influenzae and Neisseria gonorrhoeae (MICs mostly less than 1 mg/l). The other Gram-negative aerobes tested were in general somewhat less susceptible, although for Acinetobacter and Pseudomonas aeruginosa MICs seldom exceeded 8 mg/l. CI-934 was more active than enoxacin against Gardnerella vaginalis (MICs 1-8 mg/l) although it was a little less active than ciprofloxacin. Bacteroides species (including about half of the fragilis group) were susceptible to CI-934 (MICs mostly 1-8 mg/l): ciprofloxacin had similar activity but enoxacin was less active. Other anaerobes tested were mostly highly susceptible to CI-934 (MICs 1 mg/l or less) but were somewhat less susceptible to enoxacin and ciprofloxacin.

Anti-Bacterial Agents↗
PubMed1986

Resistance as a cause of treatment failure.

Clinicians and microbiologists both vary in their views on the usefulness of in-vitro antibacterial sensitivity tests, and on the significance of in-vitro resistance. This seems to relate to the fact that conditions in most in-vitro tests are remote from those in the patient, and that at best the designation 'resistant' depends on a pragmatic consensus. Furthermore, results of treatment are difficult to assess in infected patients because of the many variables that affect outcome. Well-designed clinical trials, when they are feasible, and the results of animal experiments, strongly suggest that, when it can be assessed, there is a good correlation between in-vitro and in-vivo results. There is a need to improve the content of clinical reports on the subject sent by microbiologists to clinicians.

Bacterial Infections↗
PubMed1986

The comparative in-vitro activity of eight newer quinolones and nalidixic acid.

The in-vitro antibacterial activity of nalidixic acid and the 4-quinolones, ciprofloxacin, norfloxacin, enoxacin, ofloxacin, pefloxacin, A-56619, A-56620 and CI-934 was assessed by determination of MICs. The 4-quinolones were all highly active against most isolates of Enterobacteriaceae, including nalidixic acid-resistant strains. Ciprofloxacin (MICs 0.002-2 mg/l) was the most active and A-56619 (MICs 0.008-32 mg/l) was the least active. A-56619, A-56620, ofloxacin, ciprofloxacin and CI-934 were highly active against Acinetobacter strains, pefloxacin and enoxacin were slightly less active, and a few strains were resistant to norfloxacin. All the compounds, including nalidixic acid, were active against Aeromonas strains (MICs 0.001-0.12 mg/l). Ciprofloxacin (MICs 0.06-1 mg/l) was the most active compound against Pseudomonas aeruginosa; A-56619 and CI-934 (MICs 1-16 mg/l) were the least active against this species. All the compounds were highly active against Haemophilus influenzae, Branhamella catarrhalis and Neisseria gonorrhoeae but the activity of all the compounds was poor against most isolates of Gardnerella vaginalis. All the 4-quinolones were active against staphylococci and CI-934 (MICs 0.03-0.25 mg/l) was the most active. CI-934 (MICs 0.06-2 mg/l) was also the most active compound against all streptococci. Most streptococci were sensitive also to ciprofloxacin (MICs 0.25-4 mg/l) but there were many isolates resistant to the other 4-quinolones. Against the anaerobic bacteria CI-934 was again the most active compound, particularly against the Gram-positive anaerobic cocci. Pefloxacin, enoxacin and norfloxacin had poor activity against most anaerobes. Ofloxacin, ciprofloxacin, A-56619 and A-56620 had good to moderate activity against all species of anaerobes except the Bacteroides fragilis group, against which none of the compounds was very active.

Acinetobacter↗
PubMed1986

The effects on beta-lactam susceptibility of phenotypic induction and genotypic derepression of beta-lactamase synthesis.

We have compared the ability of beta-lactam antibiotics to induce beta-lactamase synthesis and antagonize the in-vitro activity of other beta-lactams and also to select mutants with derepressed beta-lactamase synthesis amongst representative Gram-negative bacilli that produce inducible beta-lactamases. Both imipenem and cefoxitin were potent inducers of beta-lactamase and were able to antagonize the activity of other beta-lactams against isolates of Enterobacter cloacae, Citrobacter freundii and Pseudomonas aeruginosa when the two beta-lactams were present simultaneously. However, there was no antagonism for any compound against any of the organisms when the imipenem or cefoxitin was removed immediately before susceptibility to the other compounds was measured. Cefotaxime was a less potent inducer of beta-lactamase and failed to antagonize the activity of other compounds, even when present concurrently with them. Neither imipenem nor cefoxitin induced beta-lactamase synthesis in a strain of Escherichia coli, nor did they antagonize the activity of other beta-lactams against this strain. Imipenem was compared with cefotaxime and cefoxitin as an agent for the selection of beta-lactam-resistant variants. Resistant variants were obtained from isolates of Ent. cloacae, C. freundii and P. aeruginosa when cefotaxime or cefoxitin was used as the selective agent. Most of them synthesized beta-lactamase constitutively and showed reduced susceptibility to a wide range of beta-lactams, but not to imipenem. Variants with reduced susceptibility to imipenem were obtained only from the two isolates of P. aeruginosa. They did not show cross resistance to other beta-lactams and were not distinguishable from the parent strains in beta-lactamase production.

Anti-Bacterial Agents↗
PubMed1986

Differentiation of Streptococcus sanguis and S. mitior by whole-cell rhamnose content and possession of arginine dihydrolase.

Whole-cell rhamnose concentrations were measured in 48 strains of streptococci resembling Streptococcus sanguis and S. mitior. Physiological characteristics were tested by the API-20/Strep system, and it was found that "typical" S. sanguis (arginine positive, aesculin positive) contained significant amounts of rhamnose, while "typical" S. mitior (arginine negative, aesculin negative) contained very low or undetectable amounts of rhamnose. Both groups contained dextran-positive and dextran-negative strains. Organisms that were more difficult to speciate (those giving positive results in the arginine or the aesculin test, but not in both) could also be divided into a rhamnose-positive and a rhamnose-negative group; with one exception, all of the rhamnose-positive strains gave a positive result with arginine in the API-20/Strep test. There were several discrepancies between the results of conventional tests for arginine and aesculin hydrolysis and those of the corresponding API test. The results of conventional tests for arginine hydrolysis did not correlate closely with rhamnose content, and conventional tests for aesculin hydrolysis were less sensitive than API tests. With the API-20/Strep system, S. sanguis can almost always be distinguished from S. mitior by its ability to hydrolyse arginine.

Arginine↗
PubMed1986

Comparison of radiometric and gas capture system for blood cultures.

A single bottle blood culture system that detects the gas produced by micro-organisms from substrates in a specially formulated medium was compared with the Bactec radiometric system. A total of 725 blood samples collected from patients with suspected bacteraemia yielded 75 clinically important isolates. Fifty five (73%) of these cultures were detected by both methods, 16 (21%) by only the Bactec system, and four (5%) by only the Oxoid system. No significant differences were found between the two systems after allowance was made for the different volume of sample inoculated into each system.

Bacteria↗
PubMed1986

Ciprofloxacin for treating urethral gonorrhoea in men.

The effectiveness of a single oral dose of ciprofloxacin in eradicating urethral gonorrhoea was assessed in 18 men who received 250 mg and 26 men who were given 100 mg. All patients, including two infected with beta lactamase (penicillinase) producing strains of Neisseria gonorrhoeae (PPNG), were cured. The drug had no effect on infection with Chlamydia trachomatis or on the incidence of post gonococcal urethritis. Ciprofloxacin may be useful in patients hypersensitive to penicillins and cephalosporins, and the drug may also be useful in urethral gonorrhoea caused by PPNG strains.

Ciprofloxacin↗
PubMed1985

Pneumococcal bacteraemia: 325 episodes diagnosed at St Thomas's Hospital.

Three hundred and twenty five episodes of pneumococcal bacteraemia occurred at St Thomas's Hospital during 1970-84, accounting for 13.3% of all episodes of bacteraemia. Twice as many cases occurred in male as in female patients, and common predisposing factors included chronic chest disease, alcoholism, haematological malignancies, cirrhosis, and sickle cell anaemia. Mortality was 28.6% overall but only 11.8% among patients who received antibiotic treatment for at least 24 hours. Most patients (261) had pneumonia, 26 had meningitis, and eight were children with occult bacteraemia. The commonest serotype of pneumococcus in adults was type 3 (39 episodes), and these strains were associated with a high mortality. Other factors determining a fatal outcome included underlying disease (such as cirrhosis, malignancy, and chronic chest disease) and extrapulmonary infection. Almost half the survivors were treated for 10 days or less and became afebrile within 48 hours.

Adolescent↗
PubMed1985

Study of cardiothoracic wound infection at St. Thomas' Hospital.

Wound infection occurred after 14.3 per cent of 433 open heart operations. In 309, saphenous veins were harvested for coronary artery bypass grafting (CABG) and 8.7 per cent of sternal wounds and 12.9 per cent of leg wounds were infected. Only 1.6 per cent of the remaining 124 patients who had open heart operations without leg surgery suffered sternal wound infections. In the CABG group sternal infection was theatre-related and significantly associated with length of pre-operative stay, diabetes and re-operation. Similar organisms were isolated from both leg and sternal wounds which suggest that organisms were transferred from legs to sternum with the veins. No clinically relevant cross infection was demonstrated. Skin disinfection and surgical technique seem more important than antibiotic prophylaxis in the control of these infections.

Bacteria↗
PubMed1985

The in-vitro activities of enoxacin and ofloxacin compared with that of ciprofloxacin.

The in-vitro activities of enoxacin and ofloxacin were compared with that of the other new 4-quinolone, ciprofloxacin. All three compounds were highly active against Enterobacteriaceae, Haemophilus influenzae and Neisseria gonorrhoeae (MICs mostly less than 1 mg/l). The other Gram-negative aerobes tested were in general less susceptible, though for Acinetobacter and Pseudomonas species (including aeruginosa) MICs seldom exceeded 8 mg/l. Ofloxacin and ciprofloxacin were more active against Gardnerella vaginalis (MICs 0.5-2 mg/l) than was enoxacin (MICs 8-32 mg/l). Staphylococci were susceptible to ofloxacin (MICs 0.12-1 mg/l) and enoxacin (MICs 0.5-2 mg/l) as well as to ciprofloxacin. Streptococci also were mostly sensitive to the compounds though the MICs of enoxacin (4-64 mg/l) were noticeably higher than those of ofloxacin (1-4 mg/l). Anaerobes were in general susceptible though, as with streptococci, ofloxacin, with activity similar to that of ciprofloxacin, was more active than enoxacin. Variants of Enterobacteriaceae with reduced susceptibility were readily selected in the laboratory with either enoxacin or ofloxacin as the selective agent. The MICs of all the 4-quinolones were usually increased four- to 16-fold for these strains; they could therefore be regarded as remaining susceptible to the newer compounds.

Bacteria↗