PubMed Health⌕ Search

Biomedical subjects

M Greenwood

Publications and source records attributed to M Greenwood.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of a new chromogenic agar for the detection of Listeria in food.

AIM: Rapid identification of Listeria in food is important in protecting consumers from infection. The development of chromogenic media such as agar Listeria according to Ottaviani and Agosti (ALOA) has allowed more rapid detection of Listeria monocytogenes, with presumptive identification of this pathogenic species after only 24 h of incubation. The aim of this study was to evaluate Oxoid chromogenic Listeria agar (OCLA) in comparison with ALOA and a traditional, nonchromogenic medium, Oxford agar. METHODS AND RESULTS: Media were compared using pure cultures, spiked food samples and naturally contaminated samples. Whilst development of typical colony morphology took 48 h on Oxford agar, Listeria spp. were frequently detected after 24 h of incubation on OCLA and ALOA. There was no significant difference in recovery between the two chromogenic media. CONCLUSIONS: Results indicate that OCLA gives equivalent recovery of Listeria spp. compared with ALOA. Whilst L. monocytogenes was frequently detected after 24 h of incubation, a 48-h incubation time was necessary to ensure detection of both L. monocytogenes and other Listeria spp. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has shown that a commercially available chromogenic medium other than ALOA is appropriate for use in the international standard method. The commercial availability of more than one medium will facilitate the more widespread use of the method, thus increasing confidence in the ability to detect L. monocytogenes in food in the presence of other Listeria spp.

Agar↗
PubMed2006

Prevalence of Listeria monocytogenes and other Listeria species in butter from United Kingdom production, retail, and catering premises.

Two recent listeriosis outbreaks involving butter prompted this first cross-sectional study on the prevalence, levels, and types of Listeria species in 3229 samples of butter from production, retail, and catering premises in the United Kingdom during May and June 2004. When the criteria of the Microbiological Guidelines were used, 99.4% of samples were found to be of satisfactory microbiological quality, 0.5% were of acceptable quality, and 0.1% were of unsatisfactory quality as a result of high levels (>100 CFU/g) of Listeria spp. The butter samples with Listeria spp. present at more than 100 CFU/g were negative for L. monocytogenes. L. monocytogenes was detected in 0.4% (n=13) of samples, all at levels of less than 10 CFU/g, and were therefore of acceptable quality. Butter was contaminated more frequently with Listeria spp., including L. monocytogenes, when packed in plastic tubs, when in pack sizes of 500 g or less, when stored or displayed above 8 degrees C, when a hazard analysis system was not in place, and when the manager had received no food hygiene training. This study demonstrates that although butter is regarded as a low-risk product, it may provide an environment for the persistence and growth of Listeria spp., including L. monocytogenes. The control of L. monocytogenes in food processing and supply systems is critical in order to minimize the potential for this bacterium to be present in foods at the point of consumption at levels hazardous to health.

Butter↗
PubMed2005

Observations on the exploration and external neurolysis of injured inferior alveolar nerves.

The inferior alveolar nerve is sometimes injured during mandibular surgery, resulting in altered sensibility. Incomplete recovery may be the result of nerve entrapment by scar tissue. Twelve patients underwent external neurolysis of the inferior alveolar nerve following prolonged sensory impairment secondary to mandibular surgery. The mean time to external neurolysis was 14 months (range 12-24 months). Five patients demonstrated improvement in sensibility, two patients returning to normal sensation. No patient had a worsening of symptoms. The results demonstrate that external neurolysis can be a useful step during surgical exploration in carefully selected patients.

Adult↗
PubMed2005

Dosing strategy for enoxaparin in patients with renal impairment presenting with acute coronary syndromes.

BACKGROUND: Phase III clinical studies have confirmed that enoxaparin is superior to standard heparin in reducing the rate of recurrent ischaemic events in patients with non-ST elevation acute coronary syndromes. Patients with moderate to severe renal impairment were, however, excluded from these studies. Due to the hydrophilic disposition of enoxaparin, accumulation is likely in patients with renal dysfunction, thereby increasing the risk of haemorrhagic complications if standard weight adjusted treatment doses are used. Arbitrary dose reduction has been reported to increase the risk of ischaemic events, presumably due to inadequate enoxaparin concentrations. AIM: The aims of this study were to investigate the influence of glomerular filtration rate (GFR) on the pharmacokinetics of subcutaneously administered enoxaparin, and to develop a practical dosing algorithm in renal impairment that can easily be used at the bedside. METHODS: Thirty-eight patients, median age 78 years (range 44-87), mean GFR 32 ml min(-1) (range 16-117) and mean weight 69 kg (range 32-95), presenting with acute coronary syndrome were recruited into the study. Approximately 10 anti-Xa concentrations were taken per patient over their period of therapy. A population pharmacokinetic model was developed using non linear mixed effects modelling techniques, utilizing the software NONMEM. Stochastic simulations were performed to identify the most suitable dosing regimen. RESULTS: Three hundred and thirteen anti-Xa concentrations were collected. A two compartment, first order input model was identified as the best baseline model. Covariates found to improve model fitting were GFR as a linear function on clearance (CL) and weight as a linear function on the central volume compartment (Vc). The fraction of drug excreted unchanged (Fu) was estimated at 71%. CL and Vc from the final covariate model were estimated as; CL (l h(-1)) = 0.681 per 4.8 l hr(-1) (GFR) + 0.229 Vc (l) = 5.22 per 80 kg (total body weight) CONCLUSIONS: Clearance of enoxaparin was predictably related to GFR estimated using the Cockroft and Gault equation, with ideal body weight used as the size descriptor. According to our model no dosage adjustment from the standard 1.0 mg kg(-1) 12 hourly is required for the first 48 h of treatment. Maintenance doses thereafter can be calculated using standard proportional adjustments based on Fu equal to 0.71.

Administration, Cutaneous↗
PubMed2005

Evaluation of chromogenic media for the detection of Listeria species in food.

AIMS: The aim of this study was to evaluate the performance of chromogenic agars, Agar Listeria according to Ottaviani and Agosti (ALOA) and Rapid L. mono agar, compared with Oxford agar for the enumeration and detection of Listeria species in food. METHODS AND RESULTS: A total of 170 food samples were examined using the three plating media. Listeria species were isolated from 63 samples. In contrast to Oxford agar, detection of Listeria colonies on chromogenic media was as good after 24 h of incubation of plates as after 48 h. While there was no significant difference in recovery of Listeria monocytogenes on the three media, recovery of other Listeria species was significantly poorer on Rapid L. mono agar compared with Oxford and ALOA agars. Recovery of species other than L. monocytogenes was significantly improved by including a secondary enrichment stage in the detection method. CONCLUSIONS: Using chromogenic agars, presumptive identification of L. monocytogenes is possible after 24 h, compared with 3-4 days using Oxford agar. However, the poor detection of species other than L. monocytogenes on Rapid L. mono agar is a disadvantage of this medium. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new information regarding the isolation of Listeria species other than L. monocytogenes from food using chromogenic plating media. This is important, as non-pathogenic Listeria species act as markers for the likelihood of presence of L. monocytogenes and allow preventive action to be taken to avoid its presence.

Agar↗
PubMed2005

Effects of ribose supplementation prior to and during intense exercise on anaerobic capacity and metabolic markers.

This study examined whether ribose supplementation before and during intense anaerobic exercise impacts anaerobic capacity and metabolic markers. Twelve moderately trained male cyclists (22.3 +/- 2.2 y; 181 +/- 6 cm, 74.8 +/- 9 kg) participated in the study. Subjects were familiarized and fasted for 8 h after standardizing nutritional intake. In a double blind and crossover manner subjects ingested either a 150 mL placebo or ribose (3 g ribose + 150 microg folate). Subjects rested for 25 min and completed 5 x 30 s anaerobic capacity tests with 3 min passive rest. Six capillary blood samples were taken prior to and after sprints for adenine nucleotide breakdown determination. The experiment was repeated 1 wk later with alternative drink. Data were analyzed by repeated measures ANOVA. No significant interactions were observed for any performance or blood variables. D-ribose supplementation has no impact on anaerobic exercise capacity and metabolic markers after high-intensity cycling exercise.

Administration, Oral↗
PubMed2004

Fracture of the radial donor site after composite free flap harvest: a ten-year review.

The options for donor sites as a source of tissue for free vascularised osteocutaneous flaps are numerous, however, the radial forearm still has an important role. This series reports the largest published record of radial donor site fracture following the harvesting of osteocutaneous radial forearm free flaps used for reconstruction after ablative surgery for malignant disease. The relevant literature is reviewed. A retrospective review of cases treated using these flaps from 1991-2000 (inclusive) is carried out. Factors involved in the aetiology of fractures are discussed. Thirteen fractures are identified from seventy one osteocutaneous flaps (18%). A statistically significant majority of fractures occur in females. Limiting the percentage of radius diameter harvested is important and beveling of the osteotomy cuts may be advantageous in minimising weakening. Prophylactic plating of the donor site, particularly in the female patient, should be actively considered. The earlier the fracture occurs in the post-operative period, the more likely the need for operative intervention.

Aged↗
PubMed2003

General medicine and surgery for dental practitioners Part 9: haematology and patients with bleeding problems.

Disorders of the blood can affect the management of dental patients. Particular oral signs may be produced. In addition healing may be affected and the choice of anaesthesia for operative procedures will be influenced. Similarly, patients who have problems with haemostasis are a concern. Surgical procedures are obvious problems. However, restorative dentistry is not trouble-free as patients with bleeding problems may present difficulties regarding the choice of local anaesthesia, as regional block techniques may be contraindicated in some patients.

Anesthesia, Dental↗
PubMed2003

General medicine and surgery for dental practitioners. Part 8: Musculoskeletal system.

Disorders of the musculoskeletal system may impact on dental management in diverse ways. Diseases of the bones may have a direct influence on treatment and joint disorders can also cause difficulties. Cervical spine involvement may lead to poor neck extension causing difficulties in providing dental treatment under local anaesthesia or allowing the provision of a safe general anaesthetic. Muscular disorders may mitigate against safe general anaesthesia. As with all medical disorders a thorough history can help to prevent many of the possible problems which may occur secondary to musculoskeletal diseases.

Anesthesia, Dental↗
PubMed2003

General medicine and surgery for dental practitioners. Part 7: renal disorders.

Patients with kidney disorders are increasingly encountered in dental practice due to improvements in medical care leading to prolonged life expectancy. In order to provide appropriate and safe dental care for these patients it is important to have a working knowledge of renal disorders and related problems.

Candidiasis, Oral↗
PubMed2003

General medicine and surgery for dental practitioners. Part 5: liver disease.

The liver has a number of important functions. It metabolises drugs and endogenous substances and contributes to their excretion by the body. Plasma proteins are synthesised in the liver which also acts as a storage organ for glycogen and vitamin B12. The liver is also important in the production of clotting factors for normal haemostatic function.

Anesthesia, Dental↗
PubMed2003

General medicine and surgery for dental practitioners. Part 3: gastrointestinal system.

Diseases of the gastrointestinal (GI) system can be relevant to the dental surgeon for several reasons. The mouth may display signs of the disease itself, for example the cobblestone mucosa, facial or labial swelling of Crohn's disease, or the osteomata of Gardner's syndrome. These are well covered elsewhere and not discussed further here. The sequelae of GI disease, for example gastric reflux producing dental erosion, iron deficiency anaemia and treatment such as corticosteroid therapy may all have a bearing on management and choice of anaesthesia.

Anesthesia, Dental↗
PubMed2003

Oral cancer: material deprivation, unemployment and risk factor behaviour--an initial study.

Regional variations in the incidence of oral cancer may be related in some cases to material deprivation. The main aim of this study was to identify in cases (and controls matched for age and sex) an index of material deprivation, employment history, smoking and alcohol habits. This prospective study comprised 100 subjects in each group and was questionnaire based. Previous studies in relation to material deprivation in oral cancer have been population based. There was a statistically significant trend for patients to come from the most deprived groups. Sixty-six per cent of the cases had experience of long-term unemployment. Although a high proportion, this was not statistically significant after multi-variable analysis due to the confounding effects of smoking and alcohol use. Such a high proportion of cases with a history of long-term unemployment requires further study to examine in detail if there is a definite link with oral cancer once the confounding effects of smoking and alcohol are removed.

Adult↗