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G French

Publications and source records attributed to G French.

At least 37 records · Page 2Linked to original sources
PubMed1998

Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae strains causing nosocomial outbreaks of infection in the United Kingdom.

Representative isolates from 10 distinct extended-spectrum beta-lactamase-producing strains of Klebsiella pneumoniae that caused hospital outbreaks in the United Kingdom from 1991 to 1994 were examined for relationships between their enzymes and plasmids. The beta-lactamases were identified by a combination of isoelectric focusing and gene sequencing. SHV-2 beta-lactamase was produced by isolates from four outbreaks, SHV-5 was involved in three, and SHV-4, TEM-15, and TEM-26 were involved in one outbreak each. All of the extended-spectrum beta-lactamases were encoded by self-transmissible plasmids, with sizes ranging from about 70 to 160 kb. No similarities between the restriction digest patterns of the extended-spectrum beta-lactamase-encoding plasmids were detected, except to some extent between those that produced TEM-15 and TEM-26. Thus, outbreaks of hospital infection with these organisms in the United Kingdom from 1991 to 1994 involved distinct organisms and resistance plasmids and appeared to be unrelated.

Aminoglycosides↗
PubMed1997

Rarity of transferable beta-lactamase production by Klebsiella species.

We report a survey of beta-lactamases and their transferability in Klebsiella spp. isolated from blood during 1992-95. beta-Lactamases were characterized by determination of isoelectric point (pI), by hybridization of plasmid DNA preparations with probes for SHV and TEM sequences and by PCR with SHV- or TEM-specific primers. There were 80 isolates of Klebsiella pneumoniae and 22 isolates of Klebsiella oxytoca. Most isolates of K. pneumoniae had a chromosomally encoded SHV-1 beta-lactamase (or a closely related enzyme); K. oxytoca also produced chromosomal beta-lactamases, but these were distinct from SHV-1. Plasmid-encoded beta-lactamases were rare in Klebsiella spp., being found in six (7.5%) isolates of K. pneumoniae and in none of the K. oxytoca. beta-Lactamase activities were relatively low (< 100 nmoles nitrocefin hydrolysed per minute per mg of protein) and ampicillin MICs were < or = 128 mg/L for most isolates of both species. However, all isolates of K. pneumoniae with plasmid-encoded beta-lactamases, three other isolates of K. pneumoniae and three isolates of K. oxytoca had high beta-lactamase activities (> 100 nmoles/mg/min) and very high ampicillin MICs (> or = 1024 mg/L).

Ampicillin↗
PubMed1997

Mechanism and stability of hyperproduction of the extended-spectrum beta-lactamase SHV-5 in Klebsiella pneumoniae.

Some isolates of SHV-5 beta-lactamase-producing Klebsiella pneumoniae K2 from a single-strain outbreak of cross-infection produced approximately five-fold more beta-lactamase than others. We investigated three possible genetic mechanisms of this hyperproduction: the presence of a more powerful promoter, an increase in plasmid copy number or an amplification of the gene on a plasmid. No differences between low and high beta-lactamase producers were detected in the promoter region of the SHV-5 beta-lactamase gene, which closely resembled that of SHV-2. SHV-5 beta-lactamase production was encoded on a low copy number plasmid, but DNA-DNA hybridization with an SHV-specific probe detected a higher gene dose in hyperproducers. The beta-lactamase hyperproduction was unstable on repeated subculture, with a reduction of about 75% after 100 generations. Hyperproducing mutants of a low-producing Klebsiella and its Escherichia coli K-12 transconjugants could be selected in vitro at a frequency of 10(-5) to 10(-6) and these variants had an increased SHV-5 beta-lactamase gene copy number on low copy number plasmids. We conclude that hyperproduction of the extended-spectrum beta-lactamase was caused by gene amplification that could be easily lost or gained in vitro. Since the change to hyperproduction occurred at a high frequency and hyperproducers showed increased resistance to many beta-lactams and beta-lactam/beta-lactamase inhibitor combinations, we suspect that these variants may readily be selected in patients during antibiotic therapy.

DNA, Bacterial↗
PubMed1995

Incidence and mechanisms of resistance to the combination of amoxicillin and clavulanic acid in Escherichia coli.

Among Escherichia coli organisms isolated at St. Thomas's Hospital during the years 1990 to 1994, the frequency of resistance to amoxicillin-clavulanic acid (tested by disk diffusion in a ratio of 2:1) remained constant at about 5% of patient isolates (10 to 15% of the 41 to 45% that were amoxicillin resistant). Mechanisms of increased resistance were determined for 72 consecutively collected such amoxicillin-clavulanic acid-resistant isolates. MICs of the combination were 16-8 micrograms/ml for 51 (71%) of these and > or = 32-16 micrograms/ml for the remainder. The predominant mechanism was hyperproduction of enzymes isoelectrically cofocusing with TEM-1 (beta-lactamase activities, > 200 nmol of nitrocefin hydrolyzed per min per mg of protein) which was found in 44 isolates (61%); two isolates produced smaller amounts (approximately 150 nmol/min/mg) of such enzymes, and two isolates hyperproduced enzymes cofocusing with TEM-2. Eleven isolates produced enzymes cofocusing with OXA-1 beta-lactamase, which has previously been associated with resistance to amoxicillin-clavulanic acid. Ten isolates produced increased amounts of chromosomal beta-lactamase, and four of these additionally produced TEM-1 or TEM-2. Three isolates produced inhibitor-resistant TEM-group enzymes. In one of the enzymes (pI, 5.4), the amino acid sequence change was Met-67-->Val, and thus the enzyme is identical to TEM-34. Another (pI, 5.4) had the substitution Met-67-->Ile and is identical to IRT-I67, which we propose now be given the designation TEM-40. The third (pI, 5.2) had the substitution Arg-241-->Thr; this enzyme has not been reported previously and should be called TEM-41. The rarity and diversity of inhibitor-resistant TEM-group enzymes suggest that they are the result of spontaneous mutations that have not yet spread.

Amoxicillin↗
PubMed1991

LGM (Vena Tech) vena cava filter: clinical experience in 64 patients.

LG-Medical (LGM) vena cava filters were inserted percutaneously in 64 patients. Each case was followed after the filter insertion. Clinical follow-up was available in all patients; in 11 patients it was the only form of follow-up. Findings were available from autopsies in seven patients, plain abdominal radiographs in 42, and duplex sonograms of the insertion vein and inferior vena cava (IVC) in 46. A filter was inserted without major complication in all patients. The filter failed to open fully in four patients and was tilted in the IVC in 15. Recurrent pulmonary embolism was found in two patients (fatal in one), and inconsequential filter migration occurred in 11. Introduction vein thrombosis occurred in four patients. IVC thrombosis, demonstrated at autopsy or sonography, was found in 14 patients (22%) and was symptomatic in six (9%). This report suggests that the LGM filter is easy to introduce, and few complications are associated with insertion. The rate of caval thrombosis, however, may be higher than previously reported.

Adult↗
PubMed1989

The bacteriology of bronchiectasis in Hong Kong investigated by protected catheter brush and bronchoalveolar lavage.

Bacteria often colonize the lower respiratory tract of patients with bronchiectasis. Although the role of these bacteria in the pathogenesis of the disease is uncertain, their accurate identification is important for epidemiologic and treatment purposes. Therefore, the aims of this study were: (1) to identify these bacteria in patients with bronchiectasis without cystic fibrosis using the protected catheter brush (PCB) in order to avoid oropharyngeal contamination, and (2) to compare the results of bronchoalveolar lavage (BAL) with PCB. Quantitative culture was performed on PCB and BAL specimens obtained from the most severely affected lobes of 23 patients with bronchiectasis. Results of PCB showed no significant growth (less than 10(3) colony-forming units [cfu]/ml) in nine patients and 17 significant isolates (greater than 10(3) cfu/ml) in the rest: H. influenzae, 5; P. aeruginosa, 4; K. ozaenae, 2; S. aureus, 2; P. fluorescens, 1; S. pneumoniae, 1; Veillonella, 1; and coag.-ve Staph., 1. For BAL, the results were the same (20 isolates) regardless of whether 10(4) or 10(5) cfu/ml was chosen as the cutoff point. More organisms were cultured from BAL specimens, and these included all but one of the organisms cultured from PCB. We conclude that the bacteriology of bronchiectasis in Hong Kong is different from that reported in sputum studies in the West (mainly H. influenzae, S. pneumoniae, and S. aureus), and with 10(4) cfu/ml as the cutoff point, BAL gives comparable results to PCB.

Adult↗
PubMed1989

Admitting whole families: an alternative to residential care.

This paper is an examination of the effectiveness of a programme (described in detail elsewhere) designed to admit whole families for short-term intensive assessment and treatment. The goals of this programme are to eliminate residential care for symptomatic children who are admitted with their families to this service, to decrease the length of stay of the symptomatic child in residential treatment, if this is required following admission of the whole family to this unit, and to provide these services at costs comparable to or less than that currently being spent with conventional residential treatment. Results stemming from a number of pre- and post-treatment measures indicate that one half of the children initially assessed and recommended for inpatient treatment had successfully avoided inpatient treatment for six months following admission of their family to this unit. For children recommended for residential care after admission of their families to the family unit, a reduction of approximately 35% of total time in residence occurred (when compared with a comparison group). A cost saving of over +12,000 per case was realized as a result of admission of the whole family when compared with residential treatment.

Adolescent↗
PubMed1988

Fatal respiratory syncytial virus pneumonitis in a previously healthy child.

Respiratory syncytial virus (RSV) is a cause of significant morbidity and mortality in infants and children with an immunocompromised status or a congenital heart disease. The following case describes a 6 8/12-year-old, previously normal child who had a fatal interstitial pneumonitis caused by RSV. Documentation of RSV as the etiologic agent and documentation of her immune status are presented. In light of recent advances in the rapid diagnosis and treatment of RSV, this virus should be considered in children with an unusual interstitial pneumonitis regardless of their known immunologic status.

Bronchi↗
PubMed1987

Plasticized polyvinylchloride as a temporary dressing for burns.

Plasticized polyvinylchloride film has been used in this burns unit for a long time for dressings before the ward round, before surgery, and when the burned patient is transferred from the casualty department to the burns unit. Plasticized polyvinylchloride film is easy to use, safe, and causes no pain. Most importantly, in the present financial climate, it is cheap.

Bandages↗
PubMed1985

The normal post-cholecystectomy sonogram: gas vs. clips.

Although both gas and heavy metals create multiple reverberations, they can be distinguished both in vivo and in vitro by the differences in origin (focus) and the duration (persistence) of the artifact. A phantom experiment showed that surgical clip artifacts emanate from short echogenic foci, and are persistent, whereas gas foci are either long or short, with evanescent artifacts. In 78 consecutive post-cholecystectomy patients, 96 per cent (24/26) of the patients with clips demonstrated multiple reverberation artifacts, whereas 6 per cent (2/31) of the patients without clips demonstrated several reverberation artifacts. Analyzing these characteristics as well as the positional relationships of reverberation artifacts in the porta hepatis and gallbladder fossa should enable one to suspect the post-cholecystectomy state and differentiate from an abnormal gas collection.

Cholecystectomy↗
PubMed1983

Plasma protein-binding and CSF concentrations of valproic acid in man following acute oral dosing.

Simultaneous cerebrospinal fluid (CSF), total and free plasma valproic acid (VPA) concentrations were measured in 17 patients receiving two weight-adjusted VPA doses as seizure prophylaxis prior to diagnostic myelography or cisternography. Free drug concentrations were similar when measured by equilibrium dialysis (ED) at 37 degrees C for 24 h (Dianorm) or by a novel ultrafiltration (UF) method (EMIT freelevel system 1, SYVA) (ED:2.3-35.5 mg-1; UF:1.3-33.6 mg-1; r = 0.78, P less than 0.002). There was wide variation in total VPA concentration (39-154 mg-1) and in free fraction (ED: 3.3-25.6%; UF: 5.9-24%). Concentration dependent protein binding was not demonstrated. CSF VPA varied between 4.2 and 25.6 mg-1 and was accurately reflected by free plasma VPA concentrations (ED: r = 0.75, P less than 0.005: UF: r = 0.93, P less than 0.001). CSF concentration also correlated with the total plasma VPA (r = 0.76, P less than 0.005). The Emit freelevel system 1 provides a rapid measure of unbound VPA in the plasma which may be suitable for routine clinical use.

Adolescent↗
PubMed1982

Admission of whole families.

This is a program description of a short-term residential unit in which whole families are assessed and treated. This unit provides an alternative treatment format for exploring situations where removal of the child appears to be the only remaining option. It also provides an in-depth consultation for agencies who are "stuck" in their treatment of family systems and allows for the teaching of family systems intervention techniques in a non-threatening way. It also allows an opportunity for an external system to reframe, what are, to the involved clinician, impasses with clinical problems. The program, because of its structure, introduces anxiety and tension into systems with chronic mental health problems. It, therefore, serves as, not a panacea, but as an adjunct to more traditional treatment for rigid and resistant systems.

Adolescent↗