Biomedical subjects

D Redfern

Publications and source records attributed to D Redfern.

5 recordsLinked to original sources

PubMed2006

Comparison of face masks in the bag-mask ventilation of a manikin.

BACKGROUND AND OBJECTIVE: We conducted a study investigating the effectiveness of four face mask designs in the bag-mask ventilation of a special manikin adapted to simulate a difficult airway. METHODS: Forty-eight anaesthetists volunteered to bag-mask ventilate the manikin for 3 min with four different face masks. The primary outcome of the study was to calculate mean percentage leak from the face masks over 3 min. Anaesthetists were also asked to rate the face masks using a visual analogue score. RESULTS: The single-use scented intersurgical face mask had the lowest mean leak (20%). This was significantly lower than the mean leak from the single-use, cushioned 7,000 series Air Safety Ltd. face mask (24%) and the reusable silicone Laerdal face mask (27%) but not significantly lower than the mean leak from the reusable anatomical intersurgical face mask (23%). CONCLUSIONS: There was a large variation in both performance and satisfaction between anaesthetists with each design. This highlights the importance of having a variety of face masks available for emergency use.

Anesthesia↗

PubMed2004

Comment on "Mobility spectrum computational analysis using a maximum entropy approach".

We point out that the comparison in Fig. 1 of the recent publication by S. Kiatgamolchai et al. [Phys. Rev. E 66, 036705 (2002)] of the proposed maximum entropy-mobility spectrum analysis (ME-MSA) with our quantitative mobility spectrum analysis (QMSA) is misleading. Rather than comparing with the more recent "improved" version of QMSA [Vurgaftman et al., J. Appl. Phys. 84, 4966 (1998)], a preliminary version that was three years older and demonstrably inferior was employed. We show that ME-MSA and the improved QMSA give quite similar results.

Comment↗

PubMed2003

Seasonal differences in the onset of the EBV-positive and -negative forms of paediatric Hodgkin's lymphoma.

In this study, we have shown that there are seasonal differences in the onset of the (Epstein-Barr virus) EBV-positive and -negative forms of paediatric Hodgkin's lymphoma (HL). This suggests aetiological differences between the two forms of this disease. EBV-positive HL might be a rare consequence of primary EBV infection.

Adolescent↗

PubMed2001

Molecular cytogenetic characterization of two non-MYCN amplified neuroblastoma cell lines with complex t(11;17).

The pediatric tumor neuroblastoma is characterized by a very variable, and at times unpredictable, pattern of clinical behavior, ranging from a benign localized tumor to an aggressive malignancy with poor prognosis. Standard clinical and pathological assessments do not always differentiate reliably between tumor subtypes and, therefore, genetic markers are now playing an increasingly important role in treatment decisions. MYCN oncogene amplification, for example, provides a useful marker of poor prognosis. However, less than one-half of all patients who present with, or who later develop, metastatic disease show MYCN amplification. Consequently, the identification of characteristic patterns of genetic alteration in the remaining tumors is of importance. In this report, we describe two new cell lines that we have established from metastatic, non-MYCN amplified, advanced stage neuroblastomas. These cell lines show a number of features in common, including unbalanced translocation between 11q and 17q, loss of 3p, 4p and 11q and gain of 17q. Therefore, they provide a valuable resource for the characterization of genetic pathways leading to aggressive tumor growth in non-MYCN amplified neuroblastomas.

Adrenal Gland Neoplasms↗

PubMed2001

South Asian ethnicity and material deprivation increase the risk of Epstein-Barr virus infection in childhood Hodgkin's disease.

In order to further define the factors associated with the observed variations in the Epstein-Barr virus-positive rate in childhood Hodgkin's disease, we have studied the effect of material deprivation (measured by the Townsend score) and ethnic origin on the frequency of Epstein-Barr virus-positivity in 55 cases of childhood Hodgkin's disease, diagnosed between 1981 and 1999, from a multi-ethnic region of the United Kingdom. Epstein-Barr virus status was determined by immunohistochemistry for the Epstein-Barr virus-encoded latent membrane protein-1. 62% of cases were Epstein-Barr virus-positive. Ethnic group was the strongest predictor of Epstein-Barr virus-positivity, with South Asians having a more than 20-fold risk of being Epstein-Barr virus-positive compared with non-South Asians. An increased risk was still present after adjusting for deprivation. Townsend scores were significantly higher (indicating more deprivation) in the Epstein-Barr virus-positive group, particularly in males. The relative risk of Epstein-Barr virus-positivity showed a gradient with increasing Townsend score; the risk being 7-times higher in the most deprived quartile compared with the least deprived group. Although the association between Townsend score and Epstein-Barr virus-positivity was reduced after adjusting for ethnic group, the risk of Epstein-Barr virus-positivity was still 3-times higher in the most deprived compared with the least deprived quartile. In addition, cases having 2 or more siblings were 5-times as likely to be Epstein-Barr virus-positive as those from smaller families. These results provide the first evidence of a strong association between Epstein-Barr virus-positive Hodgkin's disease and South Asian children from the United Kingdom. In addition, deprivation may increase the likelihood of Epstein-Barr virus-positive disease independently of ethnicity.

Adolescent↗