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D Lewis

Publications and source records attributed to D Lewis.

At least 55 records · Page 3Linked to original sources
PubMed1997

Less fog on the Tyne? Programme budgeting in Newcastle and North Tyneside.

Programme Budgeting (PB) has been widely promoted as a model for the better conduct of the work of Health Authorities in the National Health Service in the United Kingdom. This paper reports on a project which looked at the development of PB in Newcastle and North Tyneside Health Authority (NNTHA), concentrating on the construction of a computerised tool for the compilation and analysis of programme budgets. The main activities carried out were a survey of user requirements for PB, a survey of data availability, the collection of data to construct programme budgets, and development of a relational database for storing and manipulating PB information. The main source of data was the Contract Minimum Data Set, which was supplemented by data from a number of other sources to give comprehensive information on spending in NNTHA. Costed activity data were produced, which could be aggregated in a large number of ways, such as by care setting (inpatient, outpatient, community, general practice, etc.), disease group (ICD9 chapter headings), case mix (Healthcare Resource Groups) and socio-demographic variables (age/sex, locality of GPs practice).

Budgets↗
PubMed1997

Mutagenic heterocyclic aromatic amines (HAAs) in 'processed food flavour' samples.

Eight samples of 'processed food flavours' (PFFs), chosen from five different categories, were analysed for their mutagenic activity using the Ames Salmonella assay, and also for the presence of eight heterocyclic aromatic amines (HAAs), namely 2-amino-3-(trideuteromethyl)imidazo[4,5-f]quinoline (IQ), 2-amino-3,8-dimethyl-imidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx), 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (4,7,8-TriMeIQx), 2-amino-I-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) using liquid chromatography and mass spectrometry (LC/MS). The isolation of HAAs was based on sequential liquid-liquid extraction procedures of samples at both acidic and basic pH values. The recoveries and the clean-up were monitored by introduction of quality control samples and by spiking with three tri-deuterated standards of HAAs. Although the results for the mutagenicity assay were comparable by testing less-purified and highly-purified extracts, the analysis for identification and quantification of HAAs by LC/MS required highly purified concentrates. Four samples had little or no mutagenic activity and these results were in agreement with their LC/MS results: they had no detectable levels (detection limits 1-3 ppb) of any of the HAAs monitored. The mutagenic activity of one sample was in complete agreement with the quantification of HAAs by LC/MS. Two samples produced strong mutagenic responses (3115 and 2664 revertants/g). In one sample, LC/MS analysis revealed the presence of 9.6 ppb IQ, whereas LC/MS of the other could not confirm the presence of any of the eight HAAs monitored. Two samples produced mild mutagenic activity (204 and 160 revertants/g), but relatively elevated concentrations of IQ (6.7 and 6.8 ng/g) by LC/MS. The extracts from all samples were tested for their modifying effects on mutagenicity of four HAAs. The discrepancy between the Ames test and the LC/MS analysis of some samples indicates several possibilities, such as the presence of some other HAAs, of their isomers or of other mutagens. In addition, the presence of mutagen modifiers (inhibitors or synergists) was observed in most samples. The results indicate that although chemical tests (e.g. LC/MS) can provide quantitative data for the HAAs monitored, the Ames mutagenicity test should also be conducted to determine the mutagenic activities of PFFs, in order to assess their health risk potential.

Amines↗
PubMed1997

Heterocyclic aromatic amine content in pre-processed meat cuts produced in Canada.

In an ongoing survey, the presence of heterocyclic aromatic amines (HAAs) was determined in processed, ready-to-eat meat products sold as 'meat cuts'. HAAs are a group of recently recognized mutagenic/carcinogenic contaminants in foods that are produced during the heat processing of meat. 16 samples of meat cuts (e.g. turkey breast, salami, chicken loaf, cooked ham, all beef meat, pepperoni, etc.), randomly purchased from supermarkets and specialty food stores in the Ottawa area, were analysed for the presence of eight HAAs. The isolation of HAAs was based on sequential liquid-liquid extraction procedures of the samples at both acidic and basic pH values. The mutagenic activity of these samples was determined using the Ames/Salmonella microsome assay with the strain TA98 plus rat liver S-9 metabolic activation. The mutagenicity of these samples ranged from undetectable to slightly active. The highest mutagenic activity, 141 induced revertants/g, was found in a smoked turkey breast sample. 11 samples were not mutagenic, including two that indicated a tendency for inhibition of the spontaneous revertants. The remaining four samples exhibited very low mutagenic activity. For chemical analysis, the extracts were purified with two solid phase extraction cartridges. Quantitative analysis was performed by using liquid chromatography for separation and mass spectrometry for detection. With the exception of trace amounts (0.4 ng/g) of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) in the sample with highest mutagenic activity, the chemical analysis did not detect the presence of any of the eight most frequently found HAAs in fried or broiled meat products. These data suggest that consumption of meat cuts does not present a serious health risk from HAA-type contaminants.

Amines↗
PubMed1997

Migraine and epilepsy.

The epidemiology of the association between migraine and epilepsy is reviewed. Migraine-related epilepsy is categorized using defined diagnostic criteria. Migraine-induced epilepsy is only one of several migraine-related epileptic syndromes.

Epilepsy↗
PubMed1997

Radiographic evaluation of breech presentation: is it necessary?

The purpose of this study was to evaluate the use of ultrasound in identifying fetal position and cervical spine flexion in breech presentations. Radiographic and ultrasonographic determinations of the type of presentation (frank, complete or incomplete) and degree of cervical spine flexion in 52 breech presentations were compared. The angle of flexion was defined as the angle between the fetal mandible and main axis of the cervical spine and categorized as full flexion, military, partial extension and full extension. Ultrasound was concordant with radiographic assessment of the type of presentation in 77% and the angle of flexion in 64% of the subjects and was even more accurate in those in labor. All cases predicted as having full flexion (< 90 degrees C) of the cervical spine by ultrasound had an angle of flexion < or = 90 degrees C on radiographic assessment. Of subjects in labor, ultrasound accurately identified the type of breech presentation in all cases. In addition, sonographic identification of full flexion of the cervical spine excludes cases of fetal neck extension and precludes the need for radiographic assessment prior to a trial of labor.

Adult↗
PubMed1997

Spatial and temporal variation in abundance of Anopheles (Diptera:Culicidae) in a malaria endemic area in Papua New Guinea.

Abundance of anophelines in 10 villages in the Wosera area of Papua New Guinea was monitored during 1990-1993. Of 85,197 anophelines collected in 1,276 paired indoor and outdoor landing catches, 40.4% were Anopheles koliensis Owen, 36.7% An. punctulatus Donitz, 14.3% An. karwari (James), 4.9% An. farauti s.l. Laveran, 3.1%, An, longirostris Brug, and 0.7% An. bancroftii Giles. Maps of average indoor biting rates were produced using a Bayesian conditional autoregressive model which allowed for heterogeneities in sampling effort over time and space. Differences in spatial distributions among species were observed among and within villages and were related to the distribution of larval habitats and vegetation. Abundance of An. punctulatus and An. koliensis decreased with distance from the main waterway and probably from a sago swamp forest at 6 villages in North Wosera. Abundance of An. punctulatus was associated negatively with those of An. farauti s.l., An. longirostris, and An. bancroftii. The latter 3 species also had relatively low ratios of indoor-to-outdoor biting rates, and earlier biting times than An. punctulatus. Human blood indices of at least 0.79 were observed for all species except An. bancroftii. Abundance of all 6 species was correlated temporally with recent rainfall, but An. koliensis, An. karwari, and An. longirostris showed greater temporal variability than the other species. An punctulatus and An. koliensis tended to occur together in time and space (index of association, I = 0.85). Weaker associations were seen between An. farauti s.l. and An. longirostris (I = 0.44) and An. koliensis and An. karwari (I = 0.34). The most frequently collected species occurred together and were concentrated near the Amugu river; the remaining species tended to occur together but in different parts of the Wosera area. The importance of understanding ecological requirements of the different Anopheles vectors and their association with key household and landscape features are discussed in relation to malaria transmission and control.

Animals↗
PubMed1996

Short and long range functions of amino acids in the transmembrane region of the sarcoplasmic reticulum ATPase. A mutational study.

Mutational analysis of several amino acids in the transmembrane region of the sarcoplasmic reticulum ATPase was performed by expressing wild type ATPase and 32 site-directed mutants in COS-1 cells followed by functional characterization of the microsomal fraction. Four different phenotype characteristics were observed in the mutants: (a) functions similar to those sustained by the wild type ATPase; (b) Ca2+ transport inhibited to a greater extent than ATPase hydrolytic activity; (c) inhibition of transport and hydrolytic activity in the presence of high levels of phosphorylated enzyme intermediate; and (d) total inhibition of ATP utilization by the enzyme while retaining the ability to form phosphoenzyme by utilization of P(i). Analysis of experimental observations and molecular models revealed short and long range functions of several amino acids within the transmembrane region. Short range functions include: (a) direct involvement of five amino acids in Ca2+ binding within a channel formed by clustered transmembrane helices M4, M5, M6, and M8; (b) roles of several amino acids in structural stabilization of the helical cluster for optimal channel function; and (c) a specific role of Lys297 in sealing the distal end of the channel, suggesting that the M4 helix rotates to allow vectorial flux of Ca2+ upon enzyme phosphorylation. Long range functions are related to the influence of several transmembrane amino acids on phosphorylation reactions with ATP or P(i), transmitted to the extramembranous region of the ATPase in the presence or in the absence of Ca2+.

Amino Acid Sequence↗
PubMed1996

A randomized study of VAD therapy with either concurrent or maintenance interferon in patients with newly diagnosed multiple myeloma.

This randomized study was designed to determine whether response to VAD chemotherapy could be prolonged by using rh alpha-2b-interferon (IFN) at a dose of 3 mU three times per week, either concurrently with VAD (VIC) or as maintenance after completion of VAD (VIF). Maintenance IFN was given for 9 months in order for the duration of IFN therapy to be similar in both groups. 72 patients were randomized between December 1988 and August 1993. The majority of patients had poor prognostic features. The objective response rate was similar in each arm, 78% in VIF and 77% in VIC. Of the 56 responders, 33 have relapsed, three died in remission, and 18 proceeded to high-dose therapy, withdrew for other reasons or were lost to follow-up and were censored from analysis at the relevant time point. Only two patients remain in remission (both in partial remission). Median PFS was 15 months for both VIF and VIC, compared with 16.5 months for a historic control group treated with VAD alone (n.s.). The estimated median survival in VIF was 43 months and in VIC 22 months, compared with 45 months in the historic controls (n.s.). These findings indicate that neither maintenance nor concurrent IFN prolongs response to VAD.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

Fetal cocaine exposure: analysis of vernix caseosa.

Preliminary data regarding the use of vernix caseosa (VC) as an alternative to other biological specimens for the determination of fetal cocaine exposure are presented. Advantages of VC analysis include its presence on all newborn babies, historical record of drug exposure, and ease of collection and storage. Fifteen samples of vernix caseosa-five from babies known to be cocaine-exposed because of a positive benzoylecgonine result from the urine and umbilical cord blood and ten from nonexposed neonates-were analyzed for the presence of cocaine and metabolites. VC samples from three of the five neonates known to be cocaine-exposed were positive for cocaine or its metabolites, the other two had little or no remaining specimen. The remaining ten were negative.

Chromatography, Gas↗
PubMed1996

Hepatitis C virus reinfection in orthotopic liver transplant patients with or without concomitant hepatitis B infection.

Although recurrence of hepatitis C virus (HCV) in orthotopic liver transplant (OLT) patients is frequent, the relationship between HCV recurrence and graft pathology, particularly in patients who also have a history of hepatitis B virus (HBV), is unclear. The recurrence of HCV after OLT was determined by reverse transcriptase-nested polymerase chain reaction (RT-PCR) in the sera and livers of 41 patients with OLT, 32 of whom underwent transplants for HCV or HBV-related disease. Results were compared with liver function tests, liver histology (including HBV immunohistochemistry), and antibody status. HCV PCR was more frequently positive in OLT patients with a history of HCV only (59%) than in those with a history of both HCV and HBV (41%) or no history of viral infection (2%). Recurrent HCV (60% overall) was associated with mild elevation of liver function tests and mild to moderate hepatitis. In patients who underwent transplants for both HCV and HBV disease, hepatitis on biopsy was more frequently associated with recurrent HBV than with recurrent HCV. We conclude that graft reinfection with HCV, which is frequent in OLT patients with or without HBV recurrence, is usually associated with only mild to moderate hepatitic changes compatible with graft survival.

Base Sequence↗
PubMed1996

Aetiological factors for oral manifestations of HIV.

OBJECTIVES: Describe the oral diseases in HIV-infected individuals in London, UK and identify social and medical factors related to the presence of specific oral diseases. DESIGN: Dental clinics. SUBJECTS: Consecutive sample of 456 patients with HIV infection. METHODS: Social and medical history and clinical examinations. Univariate and logistic regression analysis. OUTCOMES: Presence of HIV-associated oral disease. RESULTS: 80% of patients with AIDS and 50% of patients with HIV had a specific oral disease. The most common diseases were hairy leukoplakia (30%), erythematous candidiasis (24%), pseudomembranous candidiasis (14%), angular chielitis (6%), necrotising periodontal disease (8%) and non-recurrent ulceration (6%). CONCLUSIONS: The presence of erythematous candidiasis was not related to advanced HIV disease. Pseudo-membranous candidiasis, hairy leukoplakia and mucosal ulceration were significantly associated with advanced HIV disease. Smoking was also identified as a strong aetiological factor in oral diseases. Longitudinal studies are required to further explore the prognostic significance of oral diseases in HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Improvement in the polyneuropathy associated with familial amyloid polyneuropathy after liver transplantation.

OBJECTIVE: To study, following liver transplantation, the neurologic progression or regression of the polyneuropathy in a cohort of patients with familial amyloidotic polyneuropathy (FAP). BACKGROUND: FAP is characterized by the relentless progression of neurologic and cardiac impairment, leading to death within 7 to 15 years after disease onset. No effective treatment to slow or halt the progression of this disease has been found to date. DESIGN/METHODS: Over the past 3 years, our FAP patients were offered liver transplantation as treatment. We report on nine patients who were followed longitudinally with serial neurologic examinations since transplantation. RESULTS: Clinically, all patients evaluated for neurologic progression reported significant improvement in general well being. No patient showed any progression in neurologic disease since receiving a liver transplant. Improvements are documented in symptomatic, autonomic, and sensorimotor neurologic disease in all patients. CONCLUSION: Our experience suggests that liver transplantation may offer hope for arrest of progression and neurologic improvement in patients with FAP.

Adult↗
PubMed1996

A retreat: the benefits to nurse education.

The informality of an educational retreat can break down traditional barriers to learning and self-knowledge. A retreat can encourage autonomy, teamwork and reflection

Education, Nursing, Baccalaureate↗
PubMed1995

PCR analysis of HIV-seronegative, heterosexual partners of HIV-infected individuals.

A cohort of human immunodeficiency virus (HIV)-discordant couples was established to evaluate risk factors associated with heterosexual viral transmission. Polymerase chain reaction (PCR) was utilized to document the HIV-uninfected status among members of discordant heterosexual couples and to rule out immunosilent infection. HIV DNA PCR specific for a gag gene region was performed on peripheral blood mononuclear cell samples from 203 HIV antibody-negative adults who have long-term heterosexual relationships with HIV-infected partners. The results were negative for 200 but consistently positive in three individuals. More extensive evaluation of these three individuals with an additional primer pair specific for the envelope gene, quantitative DNA PCR, multiple additional time points, and variable nucleotide tandem repeat analyses revealed specimen processing problems in two cases but an apparent true positive PCR assay in the third case. This subject remains antibody and PCR negative for a 32-month follow-up period. These results confirm previous studies that document a negligible incidence of occult HIV infection as delineated by PCR in antibody negative heterosexual partners of HIV-infected individuals. Specimen processing errors occur at a low rate (1% in this study) and require careful evaluation. The possibility of transient, aborted infection versus successful infection with a long immunosilent period was observed in a single individual. Definitive resolution of infection status will require long-term evaluation.

Adult↗