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D Fallon

Publications and source records attributed to D Fallon.

At least 19 recordsLinked to original sources
PubMed2003

Adolescents accessing emergency contraception in the A&E department - a feminist analysis of the nursing experience.

This paper outlines the findings and discussion of a qualitative research study that focused on the experiences of seven qualified nurses working in three Accident and Emergency (A&E) departments in the North West of England. It was exploratory in nature, aiming to describe and explain the nurses' encounters with adolescents accessing emergency contraception (EC) in A&E. The study was carried out using a feminist methodology and a grounded theory method. The findings indicated that accident and emergency is a contradictory location for access to EC for adolescents, where the 'promise' of easy, confidential access contrasts sharply with the nurse's description of reality. The nurse's role is similarly contrasting, where their ideal is counter balanced by organisational limits, and is further shaped by both personal and professional guiding philosophies. The nurse's perceptions of the adolescents revealed the contradiction of both sympathetic and judgmental attitudes towards them, including an 'interpretation' of the reasons the adolescents gave for their attendance. These encounters led to a series of health, legal, and moral dilemmas for the nurses, and a strategy of referral of the adolescents to other agencies was used by them whenever possible.

Adolescent↗
PubMed2003

A comparison of the performance of commercially available chromogenic agars for the isolation and presumptive identification of organisms from urine.

AIMS: To compare four media-UTI medium, BBL CHROMagar, CPS ID2, and Harlequin CLED-using a collection of fully characterised organisms and subsequent "field trial". METHODS: Seven hundred and eighty seven fully characterised isolates (730 Gram negative bacteria, 47 Gram positive bacteria, and 10 yeasts) were used to test for accuracy of organism identification. To assess isolation rates and ability to detect mixed cultures, 1435 urine samples were cultured in the three best performing chromogenic media (UTI medium, BBL CHROMagar, and CPS ID2) and CLED. RESULTS: The chromogenic agars differed in their accuracy of identification, with BBL CHROMagar performing best and Harlequin CLED performing least well. Similarly, BBL CHROMagar achieved a higher overall isolation rate than UTI medium and CPS ID2. When mixed growth was defined as greater than two organism types, BBL CHROMagar detected more mixed cultures than did UTI medium and CPS ID2, although the differences were not significant. When mixed growth was defined as greater than one organism type the increased number of mixed growths detected by BBL CHROMagar became significant, largely because of differences in enterococcal isolation rates. CONCLUSION: The use of BBL CHROMagar, UTI medium, or CPS ID2 chromogenic agar as a replacement for CLED agar would improve the detection rate of contaminated urine samples. Enhanced identification helps to distinguish different species, facilitating the monitoring of bacterial resistance in support of the national antibiotic strategy. BBL CHROMagar gave the highest overall organism recovery rates, greatest ability to detect mixed cultures, and the most accurate identification of organisms.

Agar↗
PubMed2002

An evaluation of the performance of XLD, DCA, MLCB, and ABC agars as direct plating media for the isolation of Salmonella enterica from faeces.

AIMS: To compare the performance of four media, singly and in combination, as direct plating media for the isolation of Salmonella enterica from human faeces. METHODS: Two thousand four hundred and nine routine, faecal samples received by four laboratories were inoculated on to xylose lysine desoxycholate (XLD), desoxycholate citrate (DCA), mannitol lysine crystal violet brilliant green (MLCB), and alpha-beta chromogenic (ABC) agars using standardised protocols, reagents, and data collection. Isolates of presumptive salmonellae were identified using standard laboratory techniques and the results were analysed statistically. RESULTS: Direct plating recovered 46 of the 60 possible isolates of Salmonella spp recovered via enrichment broth. No isolates were recovered from direct plating that were not recovered via selenite enrichment. MLCB gave the highest isolation rate individually (84.8%) and amounts of competing flora (CF) did not affect the recognition of colonies. ABC proved highly specific, but insensitive, and isolation rates were adversely affected by any amount of CF. Isolation rates from XLD and DCA were only affected when the CF load was heavy. DCA was least specific, with only 9.01% of picks positive and greatest number of confirmatory tests. XLD and MLCB, in combination, gave the highest isolation rate. CONCLUSIONS: Where the earlier results of direct plating may be advantageous, XLD and MLCB provide the optimal combination. For non-typhi salmonellae, MLCB is the best, single direct plating medium. For routine diagnostic work, XLD is most effective.

Bacteriological Techniques↗
PubMed2002

A comparison of the performance of cystine lactose electrolyte deficient (CLED) agar with Oxoid chromogenic urinary tract infection (CUTI) medium for the isolation and presumptive identification of organisms from urine.

AIMS: As part of the UK antimicrobial resistance strategy and action plan, the Public Health Laboratory Service (PHLS) is required to collect antibiotic susceptibility data so that resistance trends and patterns can be monitored. Most laboratories report urine Gram negative isolates, as "coliforms" according to morphological appearance, but without an acceptable identification system the antimicrobial surveillance data will be meaningless. Commercially available identification systems tend to be expensive and time consuming. Chromogenic agars, which claim to improve the detection of mixed cultures and identification of organisms from urine, have now become available and may provide a cost effective alternative. The primary aim of this study was to compare the performance of cystine lactose electrolyte deficient (CLED) agar with a chromogenic agar (Oxoid urinary tract infection medium; CUTI) in terms of isolation rates and ability to detect mixed cultures. Secondary aims were to evaluate the correlation of "presumptive" identification of isolates from chromogenic media with that of two commercial identification systems and to appraise the sensitivity of the semiquantitative loop and filter paper strip culture techniques. METHOD: One thousand, four hundred and sixty six urine samples were examined in four laboratories using the semiquantitative culture methods of 1 microl loop and filter paper strip. The degree of accuracy of organism identification was measured by comparing the presumptive identification using colony colour supplemented with simple bench tests, with identification obtained from two more complex commercial systems. RESULTS: There was no significant difference between the performance of the loop and filter paper strip methods on the CLED agar, but the CUTI agar performed significantly better than the CLED agar for the detection of significant isolates and mixed cultures. This difference was greater using the loop method. Identification of the organisms using the commercial systems gave > 99% agreement and was therefore considered suitable as a standard against which to compare the presumptive CUTI identification. Using the manufacturer's colony colour criteria in combination with a bench indole test, the CUTI medium was 99% specific for Escherichia coli, although this was reduced to 97% if the indole test was omitted. Citrobacter spp were the most commonly misidentified organisms, giving false presumptive identification as E coli. By testing oxidase activity to differentiate Pseudomonas spp and the absence of indole production to support the identification of Proteus mirabilis, the CUTI medium provided a suitable identification for 86.8% of Gram negative isolates. The remaining 13.2% would require further identification. CONCLUSION: CUTI medium improves the detection of mixed cultures, thereby improving the reliability of reporting of significant isolates when compared with CLED agar. When supplemented with simple bench tests it provides an identification system capable of speciating 86.8% of Gram negative isolates and providing a valuable cost effective mechanism for antimicrobial resistance surveillance.

Agar↗
PubMed2002

Effect of incubation temperature on the isolation of thermophilic species of Campylobacter from faeces.

Although no large-scale clinical study has been performed, it has been reported that incubation at 37 degrees C gives better isolation rates for all common species of Campylobacter than incubation at 42 degrees C, while also improving the recovery of the more unusual species. In this study, 2,570 faecal samples were examined in four laboratories, using a standardised protocol. Isolation rates of Campylobacter spp. were compared after incubation on modified campylobacter blood-free selective agar at 37 degrees C and 42 degrees C. Campylobacter spp. isolates were made from 185 samples (7.2%); 25 were recovered only at 42 degrees C and three only at 37 degrees C (p < 0.001). There were significantly more colonies at 42 degrees C (p = 0.001). Competing flora were heavier at 37 degrees C, but this did not account for the difference in isolation rates or quantity of growth. It is recommended that cultures for Campylobacter spp. be routinely incubated at 42 degrees C. More specific techniques are required to seek for fastidious campylobacters.

Agar↗
PubMed2002

Comparison of the performance of lactose and mannitol selenite enriched broths, subcultured to DCA and XLD agars, in the isolation of Salmonella spp. from faeces.

Selenite-based enrichment broths using either lactose or mannitol as a carbohydrate source are generally used as selective enrichment media for the isolation of Salmonella spp. from human faeces in the UK, but few studies have compared the relative efficacy of the available formulations. A variety of solid media is used for the routine subculture from these selective broths, but similarly we have been unable to find published evidence as to which medium performs best. Four thousand and nineteen faecal samples were examined in four laboratories and the isolation rates of Salmonella spp. from lactose (LS) or mannitol selenite (MS) broths, plated onto either xylose lysine desoxycholate agar (XLD) or desoxycholate citrate agar (DCA) were compared. MS performed significantly better than LS (p = 0.02), recovering 95 salmonellae compared with 87. No significant difference in isolation rates was found between XLD and DCA, although colonial appearances of suspected salmonellae on XLD were much more specific, resulting in significantly fewer colonies having to be selected for supplementary testing (p < 0.001) and so reducing confirmatory work. An opportunity exists to simplify holdings of media by choosing to use the MS/XLD combination.

Bacteriological Techniques↗
PubMed2001

A comparison of the performance of bacitracin-incorporated chocolate blood agar with chocolate blood agar plus a bacitracin disk in the isolation of Haemophilus influenzae from sputum.

The lack of selectivity of chocolated blood agar (CBA), routinely used for the isolation of Haemophilus influenzae, may lead to masking of the growth of H. influenzae due to overgrowth of competing flora. Bacitracin can be used as a selective agent, either incorporated into the medium or applied to the medium in a filter paper. However, neither method has been evaluated or compared in a large study. Sputum samples (1990) were examined in four laboratories and the isolation rates of H. influenzae on chocolated blood agar with bacitracin added to the medium (BCA) and chocolated blood agar (CBA) with a bacitracin disk were compared. A plain blood agar plate was also inoculated to facilitate the isolation of Streptococcus pneumoniae so that its effects on the isolation of H. influenzae could be assessed. No significant difference was found between the isolation rates of H. influenzae on BCA and CBA with a bacitracin disk, although competing flora was greatly reduced and quantity of growth of H. influenzae increased on BCA. The presence of S. pneumoniae did not affect the isolation of H. influenzae in this study.

Anti-Bacterial Agents↗
PubMed2001

A comparison of the isolation rates of Salmonella and thermophilic Campylobacter species after direct inoculation of media with a dilute faecal suspension and undiluted faecal material.

Regardless of media used, dilution of faecal samples before direct plating may improve isolation rates and reduce subcultures by freeing organisms from the faecal mass and diminishing competing flora. Despite the routine use of dilution in many laboratories, it has never been established properly whether direct or dilute inocula should be used in primary plating of faeces. A total of 3764 faecal samples was examined in four laboratories with a standardised methodology. The isolation rates, competing flora and confirmatory work performed for Salmonella spp. and Campylobacter spp. from primary plating media with a dilute faecal inoculum were compared with those after direct inoculation of faecal material. Inoculum effects on the isolation of Shigella spp. could not be assessed as only one isolate occurred during the study period. The overall isolation rates of both major enteric pathogens were unaffected by the inoculum. However, significantly fewer wasted subcultures were recorded with a dilute inoculum for Campylobacter spp., and competing florawas reduced in all cases without diluting out small numbers of the pathogen.

Campylobacter↗
PubMed2000

Occurrence and distribution of the entomopathogenic nematodes Steinernema spp. and Heterorhabditis indica in Indonesia.

Soil samples from 79 sites on five islands of Indonesia were baited with insects for the recovery of entomopathogenic nematodes. Heterorhabditis and Steinernema were equally prevalent, and were recovered from 11.7% of samples representing 20.3% of sites sampled. Both genera were recovered from coastal sites only. Entomopathogenic nematodes were more prevalent on the Moluccan islands of Ambon and Seram than on Java or Bali. They were not detected on Sulawesi, where non-coastal sites only were sampled. RFLP analysis was used in the identification of nematode isolates. Heterorhabditis indica was the only heterorhabditid identified. Two RFLP types of Steinernema were identified.

Animals↗
PubMed1999

A comparison of blood agar supplemented with NAD with plain blood agar and chocolated blood agar in the isolation of Streptococcus pneumoniae and Haemophilus influenzae from sputum. Bacterial Methods Evaluation Group.

Streptococcus pneumoniae grows well and generally exhibits typical morphology on Columbia blood agar, whereas Haemophilus influenzae requires a more complex medium to meet its growth requirements - usually chocolated blood agar - on which S. pneumoniae is less easily recognisable. Therefore, a single medium that produces typical morphology of S. pneumoniae and facilitates the growth of H. influenzae would have considerable potential advantages. It has been claimed that blood agar supplemented with nicotinamide adenine dinucleotide (NAD) is such a medium. However, despite its routine use in several large diagnostic laboratories its performance has never been properly evaluated. In the present study, 1724 sputum samples were examined in four laboratories. The isolation rates of H. influenzae and S. pneumoniae on NAD-supplemented blood agar (SBA) were compared with those on a two-plate combination of plain blood (BA) and chocolated blood agar (CBA). The two-plate combination performed significantly better for both organisms; isolation rates for H. influenzae were increased from 8.16% on SBA to 11.07% on BA plus CBA and for S. pneumoniae from 4.18% to 4.68%. Isolation rates were also compared after incubation for 24 and 48 h. With the two-plate combination, isolation rates for H. influenzae and S. pneumoniae were increased by 0.98% and 0.16%, respectively, and for SBA by 0.57% and 0.32% after 48 h. However, despite this increase, SBA still performed less well than the two-plate combination.

Agar↗
PubMed1991

Practice patterns and costs of hospitalization for upper gastrointestinal hemorrhage.

We conducted an observational study at three hospitals in Boston to examine the patterns of practice and the costs involved in the medical management of noncirrhotic, upper gastrointestinal bleeding. A total of 111 patients were identified and studied: 42 from hospital 1, 38 from hospital 2, and 31 from hospital 3. There were no significant differences in the management of the patients, except for the more frequent use of upper gastrointestinal radiography at hospital 3 and the more frequent use of cimetidine at hospital 2. Only a small percentage (3-7%) of patients required surgery, and overall mortality (0-8%) was low. The average cost of hospitalization, determined by using the New England Medical Center cost model, was calculated for direct costs ($3,180). The majority of costs incurred were for hospital bed or intensive care unit stay (63%) and transfusion of blood products (14%), with costs for physicians' services (9%), endoscopy (2%), and upper gastrointestinal radiography (1%) accounting for only a small percentage. This study demonstrates remarkable similarity in practice patterns and resource utilization at three different hospitals and provides data on the actual costs involved in hospitalization for noncirrhotic, upper gastrointestinal hemorrhage.

Acute Disease↗
PubMed1990

Vaginal birth after cesarean delivery: results of a 5-year multicenter collaborative study.

Cesarean delivery has become the most frequently performed major operation in the United States. Widespread use of vaginal birth after previous cesarean delivery could potentially eliminate up to one-third of cesareans. However, many physicians have been reluctant to adopt this policy without large studies conclusively demonstrating its safety. This study evaluated the maternal and perinatal outcomes of over 5000 cases of labor after previous cesarean delivery. This multicenter study began in 1984 and initially included nine California hospitals. During the first 2 years, there were 1776 trials of labor resulting in 1314 vaginal births. In January 1986 two additional hospitals joined the collaborative project. Over the next 3 years, there were 3957 trials of labor resulting in 2977 vaginal births at the 11 participating hospitals. During the entire study period, 5733 patients opted for a trial of labor and 4291 (75%) delivered vaginally. There were no maternal deaths in the trial-of-labor group, and perinatal mortality was not significantly different from that of the general obstetric population. These results support the findings of numerous smaller studies that have concluded that the policy of routine repeat cesarean delivery should be abandoned.

California↗
PubMed1988

Vaginal birth after cesarean section: results of a multicenter study.

Cesarean section is now the most frequently performed major operation in the United States. Nearly one out of every four American babies is delivered by this operation. "Elective repeat" has become the most common indication for cesarean section. Although the safety of vaginal birth after cesarean section has been documented in several recent publications, automatic repeat cesarean section remains the rule in this country. We present one of the largest series of trial of labor ever reported. Of 57,553 live births, 4929 (8.6%) were of women with prior cesarean sections. Among 1776 patients who underwent a trial of labor, 1314 (74%) delivered vaginally. There was no maternal or perinatal mortality related to uterine scar rupture. Thus during the study period 1314 major operations were avoided. We conclude that, for the vast majority of women, allowing a trial of labor is a safe alternative to automatic elective repeat cesarean section.

Adult↗
PubMed1985

Testing for physician-induced demand with hypothetical cases.

It has been hypothesized that there is more demand creation by doctors in high physician density areas. Empirical tests of actual utilization have had difficulties accounting for potential confounders, particularly possible differences in the health status of diverse populations. To eliminate that problem, physicians were presented with identical, hypothetical medical cases. Actual physician density was significantly and positively correlated with the aggressiveness of proposed treatment, holding constant other physician characteristics. This result lends support for the hypothesis of demand-inducement.

Angina Pectoris↗
PubMed1973

Behavioral aftereffects of reinforcement and its omission as a function of reinforcement magnitude.

Rats responded on a multiple fixed-interval fixed-interval schedule of reinforcement. Each complete cycle of the multiple schedule was separated from the next by a relatively long period of timeout from all schedule contingencies. A response at the end of the second component of each cycle was always reinforced with an invariant reinforcement magnitude, while reinforcement magnitude and reinforcement omission were systematically varied in the first component. Response rate in the first component was a monotonic function of reinforcement magnitude in that component. These changes in response rate in the first component did not affect response rate in the second component. When reinforcement was omitted on 50% of occasions in the first component, following reinforcement there was a reduction in response rate in the second component that was monotonically related to reinforcement magnitude. Following reinforcement omission there was an increase in response rate in the second component that was unrelated to reinforcement magnitude. When reinforcement was omitted on 100% of occasions in the first component, behavioral contrast was observed.

Journal Article↗