302. Characterisation of lipopolysaccharide (LPS) receptor expression and the inflammatory response of the rat testis

Inflammation in the testis is disastrous for the developing spermatogenic cells, leading to temporary and sometimes permanent sterility. The majority of testicular macrophages display a unique protective phenotype whereby production of some key inflammatory mediators, specifically interleukin-1β (IL-1β), tumour necrosis factor-α (TNFα) and NO, in response to stimulation with LPS is relatively poor. Leydig cells and Sertoli cells also respond to high doses of LPS, producing the inflammatory cytokines, particularly IL-1α and IL-6. Although these data suggest that the LPS receptor (toll-like receptor 4, TLR4) and its associated binding proteins, CD14 and MD2, are expressed on several testicular cell types, expression of these proteins in the testis has not been described previously. Using real-time PCR and Western blotting, we established that TLR4, CD14 and MD2 are all expressed by testicular macrophages, Leydig cells, Sertoli cells, spermatocytes and round spermatids. Unexpectedly, the spermatogenic cells displayed the highest level of TLR4 surface expression as determined by flow cytometry. There was no response of the spermatogenic cells to LPS stimulation in vitro, at least in terms of mRNA expression for the inflammatory cytokines, IL-1α, IL-1β, TNFα, IL-6, activin A and the chemoattractants, CXCL-1 and CXCL-2. Although production of several cytokines was relatively diminished, testicular macrophages responded to LPS with a significant increase in mRNA expression for all of these inflammatory regulators. These data indicate that the protective phenotype of the testicular macrophages is not due to insensitivity to LPS or absence of the receptor, but may involve downstream regulation of specific inflammatory responses. The data also suggest that spermatogenic cells are capable of responding to TLR4 ligands, although not by producing inflammatory mediators. The actual function of the LPS receptor on the spermatogenic cells remains to be discovered.

Asthma severity and adequacy of management in accident and emergency departments in France: a prospective study

BACKGROUND

Recent guidelines have enabled doctors to establish accident and emergency department management strategies for acute asthma on the basis of severity of exacerbations at presentation. However, there is no available information on acute asthma patients classified according to severity of disease. Our aim was to describe the severity of such exacerbations at presentation, and the adequacy of treatment and management.

METHODS

We did a 12-month multicentre cross-sectional observational cohort study in adult patients with acute asthma who attended one of 37 accident and emergency departments in France. The doctors who examined the patients obtained information using a formatted chart. We classified exacerbations according to severity (life-threatening, severe, or mild to moderate), on the basis of clinical findings and peak expiratory flow value, as defined by currently used guidelines.

FINDINGS

Of 3772 patients with acute asthma, 975 (26%) had life-threatening attacks, 1834 (49%) had severe exacerbations without life-threatening features, and 963 (26%) had mild to moderate exacerbations. Initial treatment included nebulised b2 agonists, anticholinergics, and systemic corticosteroids in 3492 (93%), 1841 (49%), and 2252 (60%), respectively. According to severity classification, anticholinergics were used in 494 (51%), 913 (50%), and 434 (45%) of patients in life-threatening, severe, and mild to moderate exacerbations groups, respectively; corticosteroids were given in 666 (68%), 1117 (61%), and 468 (49%), respectively. The overall admission rate was 54.2%, and mean stay was 6.1 (SD 6.0) days. Patients were admitted in 747 (77%), 1018 (55%), and 278 (29%) of cases in life-threatening, severe, and mild to moderate groups, respectively. Three patients died in hospital.

INTERPRETATION

Acute asthma exacerbations are often life-threatening in patients who attend accident and emergency departments, and management of patients is not ideal, mainly because of underuse of corticosteroids and inappropriate admission rates according to severity.

Nail staining from hydroquinone cream

Topical hydroquinone is used in the treatment of a number of skin conditions. A 33-year-old male presented with brown discolouration of the fingernails following the application of 4% hydroquinone in sorbolene cream and 0.1% tretinoin cream to the face intermittently for 9 months. The discolouration resolved when the creams were ceased.

Risk factors for coronary heart disease and persistent infection with Chlamydia pneumoniae or cytomegalovirus: a population-based study

BACKGROUND

A large number of epidemiological and pathological studies have reported on associations between coronary heart disease and persistent infection with Chlamydia pneumoniae or cytomegalovirus, but relatively few have reported on possible relations between these infections and vascular risk factors.

OBJECTIVE

To determine whether serum concentrations of immunoglobulin G antibodies to C. pneumoniae or cytomegalovirus are correlated to standard vascular risk factors, markers of inflammation and indicators of socioeconomic status.

METHODS

We performed a cross-sectional sero-epidemiological study nested within a randomized trial involving five general practices in Bedfordshire, UK. We made measurements of a number of standard vascular risk factors, serum markers of systemic inflammation and other relevant characteristics in 704 individuals.

RESULTS

There were significant associations between C. pneumoniae immunoglobulin G levels and male sex and cigarette smoking (2P < 0.01 for each) and between cytomegalovirus immunoglobulin G levels and age (2P < 0.001). Other factors were not significantly associated with serum antibodies to either persistent infection.

CONCLUSIONS

Serological evidence of persistent infection with C. pneumoniae or cytomegalovirus in this population was not strongly associated with most standard vascular risk factors and other characteristics. The main implication is that such risk factors are not likely to be important confounders or mediators of the reported associations between coronary heart disease and these agents.

Dietary questions as determinants of mortality: the OXCHECK experience

OBJECTIVE

To determine whether responses to simple dietary questions are associated with specific causes of death.

DESIGN

Self-reported frequency intakes of various classes of foods and data on confounding factors were collected at the baseline survey. Death notifications up to 31 December 1997 were ascertained from the Office for National Statistics. Relative risk (RR) of death and 95% confidence intervals (CI) associated with baseline dietary factors were calculated by Cox regression.

SETTING

Prospective follow-up study based on five UK general practices.

SUBJECTS

Data were used from 11,090 men and women aged 35-64 years (81% of the eligible patient population) who responded to a postal questionnaire in 1989.

RESULTS

After 9 years of follow-up, 598 deaths were recorded, 514 of these among the 10,522 subjects with no previous history of angina. All-cause mortality was positively associated with age, smoking and low social class, as expected. Among the dietary variables, all-cause mortality was significantly reduced in participants who reported relatively high consumption of vegetables, puddings, cakes, biscuits and sweets, fresh or frozen red meat (but not processed meat), among those who reported using polyunsaturated spreads and among moderate alcohol drinkers. These associations were broadly similar for deaths from ischaemic heart disease (IHD), cancer and all other causes combined, and were not greatly attenuated by adjusting for potential confounding factors including social class.

CONCLUSIONS

Responses to simple questions about nutrition were associated with mortality. These findings must be interpreted with caution since residual confounding by dietary and lifestyle factors may underlie the associations.

PCP in the freshwater and marine environment of the European Union

This study collates monitoring data principally from 1991 to 1996, relating levels of pentachlorophenol (PCP) in the freshwater and marine environments of the European Union (EU) Member States of Belgium, France, Germany, the Netherlands and the UK. In general, PCP levels in the open freshwater and marine environments displayed a downward trend in these countries, and where increased PCP concentrations were observed, these were tentatively linked to specific point discharges. The monitoring data were compared against the relevant predicted no-effect concentration (PNEC) for PCP in a particular environmental medium. On this basis, the study suggests that PCP does not pose a risk to the coastal, estuarine, marine waters or marine sediments of the above countries, and that any risks posed by PCP to the freshwater environment can largely be attributed to sediments contaminated with PCP from historic usage, or due to the continued use of small quantities of sodium pentachlorophenyl laurate in northern France. Further analysis of the data was not possible owing to the lack of systematic reporting by Member States, the lack of information on usage quantities and patterns, and inconsistent environmental surveillance and reporting of environmental data. This is particularly relevant for south-west France, Portugal and north-east Spain, the region which accounts for almost 90% of the EU's consumption of NaPCP. These issues need to be addressed at a pan-European level to better inform the selection of risk management measures and to improve the effectiveness of such measures.

Risk factors for coronary heart disease and acute-phase proteins. A population-based study

AIMS

Circulating levels of C-reactive protein and serum amyloid A protein increase markedly, and albumin levels fall, during the acute-phase response to tissue injury, infection and inflammation. Some acute-phase proteins have been associated with increased risks of coronary heart disease in long-term prospective studies. The aim of the present study was to determine whether circulating concentrations of C-reactive protein, albumin and serum amyloid A protein are correlated with one another, standard vascular risk factors, markers of persistent infection, or indicators of socio-economic status.

METHODS AND RESULTS

We report a cross-sectional study of 704 individuals without a history of coronary heart disease from five general practices in Bedfordshire, U.K. Plasma levels of C-reactive protein and serum amyloid A protein were strongly associated with each other (2 P<0.00001) and inversely related to levels of serum albumin (2 P<0.00001). There were highly significant associations of plasma C-reactive protein concentrations with cigarette smoking and obesity (2 P<0.00001 for each). Serum albumin levels were strongly associated with blood pressure (2 P<0.0001) and plasma lipids (2 P<0.001), and concentrations of serum amyloid A protein were strongly correlated with obesity (2 P<0.0001).

CONCLUSION

Previously reported long-term prospective studies have found an increased risk of coronary heart disease of about 50% in people with raised baseline levels of plasma C-reactive protein or low albumin. The strong cross-sectional associations we have found between levels of these proteins with each other and with concentrations of serum amyloid A protein suggest that some underlying process related to inflammation is likely to be of relevance to the causation of disease. Further studies are needed to determine if the strong associations of plasma levels of C-reactive protein with cigarette smoking and obesity indicate that this particular protein can mediate some of the effects of those risk factors on coronary heart disease.

Effects of cigarette smoking and its cessation on body weight and plasma leptin levels

Smokers weigh less than age-matched nonsmokers, and most smokers gain weight after smoking cessation due to an increase in food intake and a decrease in energy expenditure. Leptin is an endocrine signal thought to regulate body fat stores through hypothalamic control of energy intake and expenditure. To determine whether the "weight-reducing" effects of smoking may be mediated by leptin, we measured plasma leptin concentrations in 22 middle-aged and older male smokers (body mass index [BMI], 28 +/- 1 kg/m2, mean +/- SEM) and 22 nonsmokers matched to the smokers for age (64 +/- 1 years) and BMI (28 +/- 1 kg/m2). The body weight and leptin concentration were remeasured at 3 and 6 months in 13 of the smokers who successfully stopped smoking. The leptin concentration correlated positively with the BMI in both smokers (r = .74, P < .001) and nonsmokers (r = .76, P < .001). However, the intercept of the regression line was higher for smokers versus nonsmokers (P < .05), with no difference in the slope. Thus, male smokers have a higher leptin level for a given BMI than nonsmokers. Following 6 months of smoking cessation, body weight increased by 7% (6.0 +/- 0.1 kg, n = 13, P < .01). Despite this weight gain, the mean leptin concentration did not increase with smoking cessation. On average, leptin levels were 25% lower than would be expected for the amount of weight gained after smoking cessation. These findings suggest that cigarette smoking directly elevates circulating plasma leptin concentrations, and this increase may be one mechanism for the lower body weight of smokers compared with nonsmokers.

Chronic infection with Helicobacter pylori, Chlamydia pneumoniae, or cytomegalovirus: population based study of coronary heart disease

OBJECTIVE

To study possible associations between coronary heart disease and serological evidence of persistent infection with Helicobacter pylori, Chlamydia pneumoniae, or cytomegalovirus.

DESIGN

Population based, case-control study, nested within a randomised trial.

SETTING

Five general practices in Bedfordshire, UK.

INDIVIDUALS

288 patients with incident or prevalent coronary heart disease and 704 age and sex matched controls.

RESULTS

High concentrations of serum IgG antibodies to H pylori were present in 54% of cases v 46% of controls, with corresponding results for C pneumoniae seropositivity (33% v 33%), and cytomegalovirus seropositivity (40% v 31%). After adjustments for age, sex, smoking, indicators of socioeconomic status, and standard risk factors, the odds ratios (95% confidence intervals) for coronary heart disease of seropositivity to these agents were: 1.28 (0.93 to 1.75) for H pylori, 0.95 (0.66 to 1.36) for C pneumoniae, and 1.40 (0.96 to 2. 05) for cytomegalovirus.

CONCLUSIONS

There is no good evidence of strong associations between coronary heart disease and serological markers of persistent infection with H pylori, C pneumoniae, or cytomegalovirus. To determine the existence of moderate associations between these agents and disease, however, larger scale studies will be needed that can keep residual confounders to a minimum.

Applying the Sheffield tables to data from general practice

Lowering cholesterol with drugs of the statin class reduces the risk of a coronary event. Recent guidelines recommend use of the 'Sheffield tables' to detect individuals who might be offered drug treatment in whom the annual absolute risk of a first coronary event is > or = 3%. Using these tables in a general practice cohort aged 35-68 years, we found that 3% of men and 0.05% of women were above the treatment threshold. Smokers aged over 50 accounted for 85% of people recommended for statin therapy. Almost all smokers would fall below the treatment threshold if they quit smoking.

Stress in the community: teaching relaxation

In this article, the author describes a project designed to offer an alternative to traditional treatment for stress. The author discusses the techniques taught to clients to help them cope with stress and the evaluation of the service for users.

The Tla protein of Porphyromonas gingivalis W50: a homolog of the RI protease precursor (PrpRI) is an outer membrane receptor required for growth on low levels of hemin

The prpR1 gene of Porphyromonas gingivalis W50 encodes the polyprotein precursor (PrpRI) of an extracellular arginine-specific protease. PrpRI is organized into four distinct domains (pro, alpha, beta, and gamma) and is processed to a heterodimeric protease (RI) which comprises the alpha and beta components in a noncovalent association. The alpha component contains the protease active site, whereas the beta component appears to have a role in adherence and hemagglutination processes. DNA sequences homologous to the coding region for the RI beta component are present at multiple loci on the P. gingivalis chromosome and may represent a family of related genes. In this report, we describe the cloning, sequence analysis, and characterization of one of these homologous loci isolated in plasmid pJM7. The 6,041-bp P. gingivalis DNA fragment in pJM7 contains a major open reading frame of 3,291 bp with coding potential for a protein with an Mr 118,700. An internal region of the deduced sequence (V304 to N768) shows 98% identity to the beta domain of PrpRI, and the recombinant product of pJM7 is immunoreactive with an antibody specific to the RI beta component. The N terminus of the deduced sequence has regional similarity to TonB-linked receptors which are frequently involved in periplasmic translocation of hemin, iron, colicins, or vitamin B12 in other bacteria. We have therefore designated this gene tla (TonB-linked adhesin). In contrast to the parent strain, an isogenic mutant of P. gingivalis W50 in which the tla was insertionally inactivated was unable to grow in medium containing low concentrations of hemin (<2.5 mg liter(-1)), and hemin-depleted cells of this mutant failed to respond to hemin in an agar diffusion plate assay. These data suggest a role for this gene product in hemin acquisition and utilization. Furthermore, the mutant produced significantly less arginine- and lysine-specific protease activities than the parent strain, indicating that there may be a regulatory relationship between tla and other members of this gene family.

The Eating Behavior Scale. A simple method of assessing functional ability in patients with Alzheimer's disease

Health care providers and family members need practical methods of assessing functional skills of individuals with Alzheimer's Disease (AD). There are neuropsychological tests that identify areas of function and dysfunction in the brain, but discrepancies have been noted between test scores and functional behaviors in activities of daily living (ADLs). The Eating Behavior Scale (EBS) was developed to measure functional ability during meals. A sample of 30 patients with probable AD were observed using the EBS during two meals on two different days. There was a strong negative correlation between meal duration and the EBS score. That is, the lower the EBS score, the longer the time required to complete the meol. Mini-Mental Status Exam (MMSE) scores were positively correlated with EBS scores. Patients with higher MMSE scores and less time since diagnosis tended to have higher EBS scores, indicating greater independence in eating.

Educating the new community children's nurses: challenges and opportunities?

This paper aims to stimulate debate around the issue of educating nurses within the new Specialist Practitioner courses in areas where no Community Children's Nursing services currently exist. The United Kingdom Central Council (UKCC) (1994) have provided the impetus and the educational structure for the development of community services for children through the publication of learning outcomes for the new, long awaited, Community Children's Nursing qualification. In outlining learning outcomes for this and the other Specialist Community Nursing Practice courses, the UKCC is clearly communicating that the care of sick children in the community should be the province of Community Children's Nurses and not held to be within the remit of other community nurses. Consequently, areas which do not currently offer a Community Children's Nursing service to these children and their families are presented with several challenges: educating nurses for these new roles; developing a new service; and redefining the roles of practitioners currently caring for these children in the community. This paper addresses the first of these challenges and identifies three factors influencing the education of these new practitioners: funding, supervision and placements. A strategic model for the support of these new students in areas with no existing service is proposed.

Health profiles of current and former smokers and lifelong abstainers. OXCHECK Study Group. OXford and Collaborators HEalth ChecK

The aim of this study was to determine the extent to which smokers and smoking quitters differ in habits and risk factors from non-smokers. Subjects comprised 8,109 patients aged 35-67 years having health checks in British primary care. We compared lifestyle and measured cardiovascular risk factors in smokers, former smokers and lifelong abstainers in cross-sectional analyses, and in prospective data in quitters. Results were adjusted for confounding factors. Considering 25 aspects of lifestyle, smokers had significantly worse habits in 20 compared to abstainers, and in 17 compared to former smokers. These included eating more white bread, full cream milk, fried food and meat, and less fruit and vegetables, wholemeal bread and bran cereals. Smokers report drinking more alcohol and taking less exercise. Smokers' mean serum levels were higher for total and low density lipoprotein cholesterol and triglycerides and lower for high density lipoprotein cholesterol. Within five years ex-smokers' data became comparable to lifelong abstainers for most factors, with apparent attenuation over up to 20 years for triglyceride, body mass index and scores for fibre and polyunsaturated fat intake. Smokers who quit after initial examinations had better health profiles even before quitting (p = 0.016) and subsequently made more beneficial health changes (p = 0.039) than continuing smokers. Smoking is associated with relatively poor health choices and risk factor levels. Stopping smoking is associated with a wide range of improved health markers beyond avoidance of tobacco toxicity.

Implementing innovations in health care settings

Innovations in health care settings are occurring at an unprecedented rate. New methods and ideas include computerized pumps, computer systems for documentation and communication, and alternative approaches to patient care. To be successfully adopted by nurses, innovations require well-planned administrative, educational and clinical support. A multi-agency research study has revealed factors that should be considered when planning innovations in health care settings.

Methylprednisolone and cyclophosphamide, alone or in combination, in patients with lupus nephritis. A randomized, controlled trial

BACKGROUND

Uncertainty exists about the efficacy and toxicity of bolus therapy with methylprednisolone or of the combination of methylprednisolone and cyclophosphamide in the treatment of lupus nephritis.

OBJECTIVE

To determine 1) whether intensive bolus therapy with methylprednisolone is an adequate substitute for bolus therapy with cyclophosphamide and 2) whether the combination of methylprednisolone and cyclophosphamide is superior to bolus therapy with methylprednisolone or cyclophosphamide alone.

DESIGN

Randomized, controlled trial with at least 5 years of follow-up.

SETTING

Government referral-based research hospital.

PATIENTS

82 patients with lupus nephritis who had 10 or more erythrocytes per high-power field, cellular casts, proteinuria (> 1 g of protein per day), and a renal biopsy specimen that showed proliferative nephritis.

INTERVENTIONS

Bolus therapy with methylprednisolone (1 g/m2 body surface area), given monthly for at least 1 year; bolus therapy with cyclophosphamide (0.5 to 1.0 g/m2 body surface area), given monthly for 6 months and then quarterly; or bolus therapy with both methylprednisolone and cyclophosphamide.

MEASUREMENTS

1) Renal remission (defined as < 10 dysmorphic erythrocytes per high-power field, the absence of cellular casts, and excretion of < 1 g of protein per day without doubling of the serum creatinine level), 2) prevention of doubling of the serum creatinine level, and 3) prevention of renal failure requiring dialysis.

RESULTS

Renal remission occurred in 17 of 20 patients in the combination therapy group (85%), 13 of 21 patients in the cyclophosphamide group (62%), and 7 of 24 patients in the methylprednisolone group (29%) (P < 0.001). Twenty-eight patients (43%) did not achieve renal remission. By life-table analysis, the likelihood of remission during the study period was greater in the combination therapy group than in the methylprednisolone group (P = 0.028). Combination therapy and cyclophosphamide therapy were not statistically different. Adverse events were amenorrhea (seen in 41% of the cyclophosphamide group, 43% of the combination therapy group, and 7.4% of the methylprednisolone group), cervical dysplasia (seen in 11% of the cyclophosphamide group. 7.1% of the combination therapy group, and 0% of the methylprednisolone group), avascular necrosis (seen in 11% of the cyclophosphamide group, 18% of the combination therapy group, and 22% of the methylprednisolone group), herpes zoster (seen in 15% of the cyclophosphamide group, 21% of the combination therapy group, and 3.7% of the methylprednisolone group) and at least one infection (seen in 26% of the cyclophosphamide group. 32% of the combination therapy group, and 7.4% of the methylprednisolone group).

CONCLUSIONS

Monthly bolus therapy with methylprednisolone was less effective than monthly bolus therapy with cyclophosphamide. A trend toward greater efficacy with combination therapy was seen.

Selective immunolesioning of the basal forebrain cholinergic system disrupts short-term memory in rats

Selective depletion of nerve growth factor receptor-bearing neurons in the basal forebrain cholinergic system nuclei by the immunotoxin 192 IgG-saporin offers a new and highly useful tool for the study of the role of the forebrain cholinergic system in cognitive functions. In the present study, we have tested the effects of 192 IpG-saporin in an operant delayed matching-to-position task which has previously been used to discriminate between delay-dependent learning impairments and delay-independent disturbances of non-mnemonic processes. Rats were first trained to criterion performance and then received intraventricular injections of 5 microg of 192 IgG-saporin 4 weeks prior to a second testing session. Rats with 192 IgG-saporin lesions displayed a significant delay-dependent decline in performance compared to normal controls, indicating a deficit in short-term memory. Administration of the muscarinic blocker scopolamine (0.5 mg/kg, i.p.) produced more pronounced impairment in the performance of the normal control rats across all delays, and induced further impairment also in animals with 192 IgG-saporin lesions. These effects were not observed following control injections of methyl scopolamine, suggesting that the impairment induced by scopolamine was due to the blockade of central muscarinic receptors. No improvement in performance was observed in either group following systemic treatment with the muscarinic cholinergic agonist arecoline (1.00 mg/kg). Biochemical and morphological analyses confirmed the selective and severe (>90-95%) depletion of cholinergic neurons throughout the septal-diagonal band area and the nucleus basalis region by the intraventricular 192 IgG-saporin treatment. Although the immunotoxin was observed to produce additional damage to the cerebellar Purkinje cells, no gross motor abnormalities were observed that could contribute to the effects on accuracy in the task used here. In conclusion, the results show that selective combined lesions of the basal forebrain cholinergic neurons in the septal-diagonal band area and nucleus basalis produce long-lasting impairments in short-term memory, thus providing further support for a role of this system in cognitive functions.

Costs and cost effectiveness of health checks conducted by nurses in primary care: the Oxcheck study

OBJECTIVE

To measure the costs and cost effectiveness of the Oxcheck cardiovascular risk factor screening and intervention programme.

DESIGN

Cost effectiveness analysis of a randomised controlled trial using clinical and economic data taken from the trial.

SETTING

Five general practices in Luton and Dunstable, England.

SUBJECTS

2205 patients who attended a health check in 1989-90 and were scheduled for re-examination in 1992-3 (intervention group); 1916 patients who attended their initial health check in 1992-3 (control group). Participants were men and women aged 35-64 years.

INTERVENTION

Health check conducted by nurse, with health education and follow up according to degree of risk.

MAIN OUTCOME MEASURES

Cost of health check programme; cost per 1% reduction in coronary risk.

RESULTS

Health check and follow up cost 29.27 pounds per patient. Estimated programme cost per 1% reduction in coronary risk per participant was between 1.46 pounds and 2.25 pounds; it was nearly twice as much for men as women.

CONCLUSIONS

The cost to the practice of implementing Oxcheck-style health checks in an average sized practice of 7500 patients would be 47,000 pounds, a proportion of which could be paid for through staff pay reimbursements and Band Three health promotion target payments. This study highlights the considerable difficulties faced when calculating the costs and benefits of a health promotion programme. Economic evaluations should be integrated into the protocols of randomised controlled trials to enable judgments to be made on the relative cost effectiveness of different prevention strategies.

Resistant starch lowers fecal concentrations of ammonia and phenols in humans

We investigated the effect of resistant starch (RS) on markers of colonic protein metabolism. Eleven subjects participated in a randomized crossover study in which they consumed either high-RS (39 +/- 3 g/d, -chi +/- SEM) or low-RS (5 +/- 0.4 g/d) diets for 3 wk. All other macronutrients were kept constant. During the high-RS diet daily excretion of fecal nitrogen increased from 1.84 +/- 0.15 to 2.86 +/- 0.42 g/d (P < 0.01) and excretion of fecal phenols fell from 9.2 +/- 1.4 to 5.3 +/- 0.8 mg/d (P < 0.01). Fecal concentrations of ammonia decreased from 397 +/- 33 to 278 +/- 49 microgram/g (P < 0.01) and phenols decreased from 69 +/- 8 to 39 +/- 10 microgram/g (P < 0.001). Daily output of urinary ammonia, urea, phenols, and total nitrogen did not change significantly, but pH decreased from 6.4 +/- 0.1 to 6.2 +/- 0.1 (P < 0.05) during the high-RS period. These results suggest that RS significantly attenuates the accumulation of potentially harmful byproducts of protein fermentation in the human colon.

Characterization, genetic analysis, and expression of a protease antigen (PrpRI) of Porphyromonas gingivalis W50

Previous studies of the serum immunoglobulin G antibody response of periodontal patients have demonstrated significant reactivity to a cell surface or extracellular arginine-specific protease of Porphyromonas gingivalis which migrates as an approximately 50-kDa band on sodium dodecyl sulfate-polyacrylamide gels. In the present report, two forms of the enzyme (ArgI and ArgIA) with this electrophoretic behavior were isolated. ArgI is a heterodimer of alpha and beta subunits, and ArgIA is a monomer composed of the catalytically active alpha component alone. The gene encoding ArgI (prpR1 encoding protease polyprotein ArgI) was cloned from Sau3AI digests of P. gingivalis W50 DNA into pUC18. Sequence analysis demonstrated that the alpha and beta components are contiguous on the initial translation product and are flanked by large N- and C-terminal extensions. prpR1 is 97.5% identical to the rgp-1 gene from P. gingivalis H66. prpR1 expression in Escherichia coli demonstrated the presence of an internal transcription-translation initiation site which could permit independent expression of different regions of the polyprotein. Immunochemical analysis of P. gingivalis mid-logarithmic-phase cultures suggested that the processing of PrpRI may be closely coupled to its synthesis, with only the final stages taking place at the cell surface. Southern hybridization studies demonstrated that the prpR1 gene is widely distributed in other P. gingivalis strains and that a second homologous locus to the alpha component and at least two other homologous loci to the beta component are present on the P. gingivalis chromosome. These data indicate that the ArgI protease of P. gingivalis is a member of a family of sequence-related gene products which may share both functional and antigenic properties.

Strategies for reducing coronary risk factors in primary care: which is most cost effective?

OBJECTIVE

To examine the relative cost effectiveness of a range of screening and intervention strategies for preventing coronary heart disease in primary care.

SUBJECTS

7840 patients aged 35-64 years who were participants in a trial of modifying coronary heart disease risk factors in primary care.

DESIGN

Effectiveness of interventions assumed and the potential years of life gained estimated from a risk equation calculated from Framingham study data.

MAIN OUTCOME MEASURE

The cost per year of life gained.

RESULTS

The most cost effective strategy was minimal screening of blood pressure and personal history of vascular disease, which cost 310 pounds-930 pounds per year of life gained for men and 1100 pounds-3460 pounds for women excluding treatment of raised blood pressure. The extra cost per life year gained by adding smoking history to the screening was 400 pounds-6300 pounds in men. All strategies were more cost effective in men than in women and more cost effective in older age groups. Lipid lowering drugs accounted for at least 70% of the estimated costs of all strategies. Cost effectiveness was greatest when drug treatment was limited to those with cholesterol concentrations above 9.5 mmol/l.

CONCLUSIONS

Universal screening and intervention strategies are an inefficient approach to reducing the coronary heart disease burden. A basic strategy for screening and intervention, targeted at older men with raised blood pressure and limiting the use of cholesterol lowering drugs to those with very high cholesterol concentrations would be most cost effective.

Transdermal clonidine compared to placebo in painful diabetic neuropathy using a two-stage 'enriched enrollment' design

Because a variety of mechanisms may generate pain in neuropathic pain syndromes, conventional clinical trial methods may fail to identify some potentially useful drugs; a drug affecting just a single mechanism may work in too few patients to yield a statistically significant result for the trial. To test a previous clinical observation that approximately one-quarter of patients with painful diabetic neuropathy appear responsive to clonidine, we conducted a formal clinical trial of transdermal clonidine in painful diabetic neuropathy patients using a 2-stage enriched enrollment design. In the first stage (study 1), 41 patients with painful diabetic neuropathy completed a randomized, 3-period crossover comparison of transdermal clonidine (titrated from 0.1 to 0.3 mg/day) to placebo patches. Twelve apparent responders from study I were entered into the 'enriched enrollment' second stage (study II), consisting of an additional 4 double-blind, randomized, 1-week treatment periods with transdermal clonidine and placebo. Study I showed that in the overall group of 41 patients, pain intensity differed little during clonidine and placebo treatment. In study II, however, the 12 apparent responders from study I had 20% less pain with clonidine than placebo (95% confidence interval (CI): 4-35% pain reduction; P = 0.015), confirming that their pain was responsive to clonidine. None of the 3 consistent clonidine responders who were tested with the alpha-adrenergic blocker phentolamine had relief of pain, suggesting that clonidine's pain relief is not mediated by a decrease in sympathetic outflow. A post-hoc analysis of many variables suggested that patients who described their pain as sharp and shooting may have a greater likelihood of responding to clonidine.(ABSTRACT TRUNCATED AT 250 WORDS)

Modelling different strategies to prevent coronary heart disease in primary care

Strategies for prevention of coronary heart disease (CHD) in primary care need to take into account the number of people who require screening, further assessment, intervention and follow-up (i.e. the patient workload generated for the general practitioner) as well as the anticipated reductions in morbidity and mortality. Risks of CHD for various risk profiles were estimated from equations produced by the Framingham study. This enabled an estimate of the number of avertable CHD events to be compared against the patient workload implications for the general practitioner when different screening and intervention strategies were used. The Framingham equations were applied to a population of 5727 men and women aged 35-64 years of age registered with general practices in the south of England. Adopting an unselective approach to screening resulted in 14.1% (n = 73) of the 517 CHD events predicted over a 10 year period being averted. A limited screening strategy, involving 25% (n = 1436) of the patients would avert 5.6% (n = 29) of the predicted CHD events, whilst more extended strategies involving between 37% (n = 2131) and 46% (n = 2660) of the practice population respectively would result in between 6.9% (n = 36) and 9.3% (n = 48) of events being averted. The marginal benefit in averting CHD events decreased as more screening criteria were included. Almost all (99%) of the people identified by the selective screening strategies would require some form of intervention, predominantly lifestyle advice. Lowering the systolic blood pressure by 15 mmHg instead of 10 mmHg was equally effective as a 5% improvement in the overall rate of smoking cessation.(ABSTRACT TRUNCATED AT 250 WORDS)

The Effects of Coffee on Serum Lipids and Blood Pressure in a UK Population

Data on coffee consumption were collected for 1074 adults attending for health checks in the OXCHECK study, to assess associations with serum lipids and blood pressure. Of the sample, 70.5% drank coffee, largely instant. Coffee had no significant effects on total or high-density lipoprotein (HDL) cholesterol or blood pressure, and was negatively correlated with serum triglycerides. The type of coffee drunk in the UK does not adversely effect these cardiovascular risk factors.

The role of PDGF-BB on the development of the collateral circulation after acute arterial occlusion

The survival of tissues in the presence of arterial occlusion is critically dependent on the development of collateral blood vessels. Identification of the biochemical mediators and their mechanism of action is fundamental to an understanding of the evolution of the collateral circulation. The ability of PDGF-BB to promote this was evaluated in an animal model of hind limb ischaemia. In order to obtain significant quantities of this mitogen for use in our animal model, human recombinant PDGF-BB was expressed in a Chinese Hamster Ovary (CHO) cell line. The transfected CHO cells produced 544 micrograms/l of PDGF-BB in serum free medium (SFM). The 30 kDa form of PDGF-BB was purified to homogeneity as judged by silver staining and amino-acid sequencing. Purified PDGF-BB was shown to be bioactive by a cell proliferation assay. The exogenous administration of PDGF-BB enhanced the recovery of blood flow after acute arterial occlusion. The results suggest that PDGF-BB may have therapeutic value in promoting collateral development following arterial occlusion.

Cardiovascular risk and attitudes to lifestyle: what do patients think?

OBJECTIVE

To examine the relation between subjects' level of cardiovascular risk and their beliefs about the harmfulness of their smoking habit, current diet, and level of exercise, together with their stated desire to modify such behaviour.

DESIGN

Self administered postal health and life-style questionnaire followed by a structured health check conducted by a nurse.

SETTING

Five general practices in Luton and Dunstable, Bedfordshire.

SUBJECTS

5803 people aged 35-64 years enrolled in the OXCHECK trial who attended for a health check before 1 March 1992.

MAIN OUTCOME MEASURES

Perceived risk to health of lifestyle behaviours, desire to modify behaviour, and a reported serious attempt to modify behaviour in the preceding year.

RESULTS

A high proportion of smokers and those who were physically inactive perceived their behaviour to be harmful (1020; (76%; 95% confidence interval 74% to 79%) and 350 (74%; 70% to 78%) respectively) and wished to modify it (1212 (79%; 77% to 81%) and 375 (74%; 71% to 78%) respectively). In contrast, only 289 (45%; 41% to 48%) of obese people and 188 (14%; 12% to 16%) of people with a high dietary fat intake perceived their current diet to be harmful. The more cardiovascular risk factors present, the more likely subjects were to perceive a health risk attached to their diet and lack of exercise (p < 0.01 in both cases) and to want to improve their diet.

CONCLUSION

Awareness of the health risk from smoking and motivation to stop is high. Further efforts are required, however, to educate the public about the risks associated with a high dietary fat intake. Although the health risks of inactivity were widely recognised, motivation to take more exercise needs to be increased.

Factors affecting response to an invitation to attend for a health check

OBJECTIVE

To describe the characteristics of general practice patients who fail to respond to an invitation to attend for a health check, in relation to demographic variables, risk factor status, health status, and attitudes to behaviour modification.

DESIGN

Postal questionnaire before invitation to attend a health check and subsequent record of attendance.

SETTING

Five urban general practices in Bedfordshire, UK.

SUBJECTS

A total of 2678 patients aged 35-64 years were invited for a health check in 1989-90.

RESULTS

The number of patients who did not attend was low overall but was higher among men than women (21 v 15%, p < 0.001), and in unmarried than married patients (24 v 16%, p < 0.001). Failure to attend was also higher among people in manual than in non-manual occupations (21 v 15%, p < 0.001), in people living in rented accommodation than in homeowners (29 v 16%, p < 0.001), and in those without access to a car than in car users (27 v 16%, p < 0.001). There was no difference in non-attendance rate according to age at completion of full time education. After adjustment for age, sex, marital state, and social class, the odds ratio for non-attendance was 1.74 (95% confidence interval (CI) 1.41, 2.14) for smokers; 1.07 (95% CI 0.76, 1.51) for heavy drinkers; 1.91 (95% CI 1.41, 2.58) for those with a less healthy diet; and 1.50 (95% CI 1.09, 2.07) for those who were obese. Patients who had visited their general practice more frequently and those who indicated a willingness to change their behaviour were significantly more likely to attend the health check.

CONCLUSIONS

Health check attendance was lowest among patients who rarely attended the surgery and those who reported higher risk behaviour. Attendance was not, however, confined to the 'worried well'. Equal numbers of those with and without chest pain attended, as did at least three quarters of those in each risk group. This high rate of attendance reflects the time and effort invested in systematic recruitment. The development of a robust recruiting strategy is essential if substantial numbers, and particularly those at highest risk, are to be reached.

Carbohydrate fermentation decreases hepatic glucose output in healthy subjects

Fermentation of undigested carbohydrate produces short-chain fatty acids (SCFA), some of which have been shown to reduce hepatic glucose production (HGP) in animals. The aim of this study was to examine whether carbohydrate fermentation decreases HGP in man. Ten healthy subjects consumed 90-g carbohydrate portions of either brown rice or barley for dinner in random order 1 week apart. The following morning, glucose kinetics were measured basally and during an oral glucose tolerance test (OGTT). HGP was calculated as the difference between the total rate of glucose appearance (calculated from % enrichment of 6,6 dideuterated glucose [6,6 D2 glucose]) and the rate of appearance of gut-derived glucose (calculated from 6-3H glucose in the glucose drink). To detect fermentation, breath H2 content was measured by end-expiratory sampling of alveolar air. Significantly more breath H2 was produced after barley consumption (24 +/- 4 v 4 +/- 1 ppm, P < .001), indicating that barley contains more fermentable carbohydrate than rice. Glucose tolerance improved after the barley meal, with the peak OGTT plasma glucose concentration being 0.7 mmol/L lower than that after the rice meal (7.7 +/- 0.4 v 8.4 +/- 0.3 mmol/L, P < .05). This was primarily due to a 30% reduction in HGP (area under the curve, 909 +/- 116 v 1,295 +/- 157 mumol/kg; P < .01). No difference in the rates of glucose disappearance or gut glucose absorption was observed. However, serum free fatty acid (FFA) concentrations were significantly reduced the morning after the barley meal. In summary, carbohydrate fermentation enhances the suppression of HGP and FFA levels by oral glucose in man.(ABSTRACT TRUNCATED AT 250 WORDS)