Case finding for chronic obstructive pulmonary disease in people attending long-term condition clinics in primary care.

Despite increased interest and awareness of chronic obstructive pulmonary disease (COPD), nearly half of the people with COPD remain undiagnosed. Inviting people at risk for screening is unlikely to be effective as many will not attend. Co-morbidities are common in people with COPD but COPD is also a comorbidity of other long-term conditions and people with these conditions are under regular review in primary care clinics. This study aimed to develop a pilot programme to case find people with COPD among patients attending other long-term clinics in primary care. Twenty-three general practices were recruited to participate in South West England. All current or ex-smokers aged ≥35 attending a long-term condition clinic who were not known to have COPD were asked to complete a questionnaire designed to help identify people with COPD and to perform microspirometry. Practices were asked to collect data on up to 100 patients. One thousand three hundred and thirty-three patients were assessed. Four hundred and ten people (31%) were current smokers. Six hundred and thirteen (46%) had high questionnaire scores and 287 (22%) of these also had a forced expiratory volume in 1 second (FEV1) below the lower limit of normal (LLN). The mean FEV1 in these patients was 59.0% of predicted (range 22-79.0%). Two hundred and twenty-four had an FEV1 between 50% and 80% of predicted, 50 had an FEV1 between 30% and 50% of predicted. One hundred and sixteen (40%) of the people with an FEV1 below the LLN were still smoking and 55 accepted referral to cessation services. A total of 56% of the other smokers assessed but not thought to have COPD also accepted referral. Assessing symptoms and performing microspirometry in people attending long-term condition clinics in primary care is feasible and has a high yield of identifying people likely to have previously undiagnosed COPD.

Rapid assessment breast clinics--evolution through audit.

This observational, cohort study aimed to examine the potential utility of Rapid Assessment Breast Clinics (RABC) beyond cancer detection at presentation. One thousand four hundred and twenty nine women were studied over an 18 month period. 154 (10.7%) had breast cancer - 87.7% of whom were seen expediently with 92.9% being diagnosed at one attendance. One hundred and forty three (10%) of those with a benign diagnosis were found by routine questioning to have significant familial risk separate to their reason for referral. Despite careful triage, considerable contamination of appointment allotment occurred with many who were correctly triaged as non-urgent being seen 'urgently'. One hundred and seventy six attendees (12.3%) had neither the symptom that triggered referral, nor breast lump, nipple discharge nor family history of breast cancer, while 283 (19.8%) had no objective clinical or radiological abnormality. Although RABC reliably categorise malignant versus non-malignant diagnoses despite cluttering by low risk women, a significant proportion of non-cancer patients still require address of future risk rather than reassurance of their present status alone.

A mathematical formulation for the cell-cycle model in somitogenesis: analysis, parameter constraints and numerical solutions.

In this work we present an analysis, supported by numerical simulations, of the formulation of the cell-cycle model for somitogenesis proposed in Collier et al. (J. Theor Biol. 207 (2000), 305-316). The analysis indicates that by introducing appropriate parameter constraints on model parameters the cell-cycle mechanism can indeed give rise to the periodic pattern of somites observed in normal embryos. The analysis also provides a greater understanding of the signalling process controlling somite formation and allows us to understand which parameters influence somite length.

Stability of atmospheric CO2 levels across the Triassic/Jurassic boundary.

The Triassic/Jurassic boundary, 208 million years ago, is associated with widespread extinctions in both the marine and terrestrial biota. The cause of these extinctions has been widely attributed to the eruption of flood basalts of the Central Atlantic Magmatic Province. This volcanic event is thought to have released significant amounts of CO2 into the atmosphere, which could have led to catastrophic greenhouse warming, but the evidence for CO2-induced extinction remains equivocal. Here we present the carbon isotope compositions of pedogenic calcite from palaeosol formations, spanning a 20-Myr period across the Triassic/Jurassic boundary. Using a standard diffusion model, we interpret these isotopic data to represent a rise in atmospheric CO2 concentrations of about 250 p.p.m. across the boundary, as compared with previous estimates of a 2,000-4,000 p.p.m. increase. The relative stability of atmospheric CO2 across this boundary suggests that environmental degradation and extinctions during the Early Jurassic were not caused by volcanic outgassing of CO2. Other volcanic effects-such as the release of atmospheric aerosols or tectonically driven sea-level change-may have been responsible for this event.

Ultrasound features of blunt testicular injury.

This is a retrospective study of ultrasound examination for patients with blunt scrotal trauma. Fifteen patients were examined over an 18-month period. The purpose of the study was to discover the ultrasonic features of blunt testicular trauma and to distinguish less severe from more severe injury with testicular rupture requiring surgery. Three had ultrasonic findings of acute testicular rupture and this was confirmed by surgery. The ultrasound features of testicular trauma with rupture are irregularity of testicular outline and inhomogeneity of testicular texture. The value of ultrasound in diagnosing patients with testicular rupture and, therefore, requiring urgent surgery is discussed. In our limited study, irregularity of testicular outline was the distinguishing feature of rupture.

Cross-cultural validation of the Inventory of School Motivation (ISM): Motivation Orientations of Navajo and Anglo students.

The Motivation Orientation scales of the Inventory of School Motivation (ISM) were validated across Navajo (n = 760) and Anglo (n = 1012) students in the U.S. Confirmatory factor analysis (CFA) supported the 8-factor structure of motivation orientations for the total sample and the Navajo and Anglo subsamples, although Navajo students did not distinguish well between the Effort and Task constructs. However, of 39 survey items, only 30 items were invariant across groups in factor loadings on respective a priori constructs. The findings show that even though the ISM Motivation Orientation scales are applicable to students of different cultural backgrounds, meaningful cross-cultural comparisons should use the 30 items that mean the same to both cultural groups; whereas studies that do not involve cross-cultural comparisons may use the complete version of the scales.

A cell cycle model for somitogenesis: mathematical formulation and numerical simulation.

After many years of research, the mechanisms that generate a periodic pattern of repeated elements (somites) along the length of the embryonic body axis is still one of the major unresolved problems in developmental biology. Here we present a mathematical formulation of the cell cycle model for somitogenesis proposed in Development105 (1989), 119-130. Somite precursor cells in the node are asynchronous, and therefore, as a population, generate continuously pre-somite cells which enter the segmental plate. The model makes the hypothesis that there exists a time window within the cell cycle, making up one-seventh of the cycle, which gates the pre-somite cells so that they make somites discretely, seven per cycle. We show that the model can indeed account for the spatiotemporal patterning of somite formation during normal development as well as the periodic abnormalities produced by heat shock treatment. We also relate the model to recent molecular data on the process of somite formation.

Diabetes and the Mediterranean diet: a beneficial effect of oleic acid on insulin sensitivity, adipocyte glucose transport and endothelium-dependent vasoreactivity.

Abnormalities in endothelial function may be associated with increased cardiovascular risk in diabetic patients. We examined the effect of an oleic-acid-rich diet on insulin resistance and endothelium-dependent vasoreactivity in type 2 diabetes. Eleven type 2 diabetic patients were changed from their usual linoleic-acid-rich diet and treated for 2 months with an oleic-acid-rich diet. Insulin-mediated glucose transport was measured in isolated adipocytes. Fatty acid composition of the adipocyte membranes was determined by gas-liquid chromatography and flow-mediated endothelium-dependent and -independent vasodilatation were measured in the superficial femoral artery at the end of each dietary period. There was a significant increase in oleic acid and a decrease in linoleic acid on the oleic-acid-rich diet (p<0.0001). Diabetic control was not different between the diets, but there was a small but significant decrease in fasting glucose/insulin on the oleic-acid-rich diet. Insulin-stimulated (1 ng/ml) glucose transport was significantly greater on the oleic- acid-rich diet (0.56+/-0.17 vs. 0.29+/-0.14 nmol/10(5) cells/3 min, p<0.0001). Endothelium-dependent flow-mediated vasodilatation (FMD) was significantly greater on the oleic-acid-rich diet (3.90+/-0.97% vs. 6.12+/-1.36% p<0.0001). There was a significant correlation between adipocyte membrane oleic/linoleic acid and insulin-mediated glucose transport (p<0.001) but no relationship between insulin-stimulated glucose transport and change in endothelium-dependent FMD. There was a significant positive correlation between adipocyte membrane oleic/linoleic acid and endothelium-dependent FMD (r=0.61, p<0.001). Change from polyunsaturated to monounsaturated diet in type 2 diabetes reduced insulin resistance and restored endothelium-dependent vasodilatation, suggesting an explanation for the anti-atherogenic benefits of a Mediterranean-type diet.

Digital fluoroscopic assessment of the scapulohumeral rhythm.

Previous studies have shown that abnormal rotation of the scapula is associated with shoulder pathology. Among the methods which have been proposed, planar x-ray measurements are probably the only methods, which enable clinicians to assess accurately and objectively the scapulohumeral function in vivo. The aim of this study was to develop a method for the assessment of scapulohumeral kinematics using digital fluoroscopy. Anteroposterior images of the right glenohumeral joint were taken, in thirty-four healthy males, with the arm at rest, 30 degrees, 60 degrees, 90 degrees, 120 degrees, 150 degrees and maximum abduction, in the scapular plane. High inter- and intra-examiner reliability was observed regarding the arm and scapular angle measurements (ICC = 0.92-0.99). The positioning of the arm at the proposed angles was also highly accurate (< 2.3 degrees misplacement) and reproducible (CV% < 5.3%). The mean radiation dose was 0.075 mSv (+/- 0.027 mSv). At the resting position the scapula was in slight downward rotation (-2.4 degrees +/- 4.3 degrees) and the arm in slight abduction (1.5 degrees +/- 6.6 degrees). The mean maximum scapular rotation and the mean maximum arm abduction was 61.4 degrees (+/- 5.2 degrees) and 162.4 degrees (+/- 6.6 degrees) respectively. A curvilinear relationship was found between the arm angle (AA) and the scapular angle (SA) (p < 0.0001). The AA:SA ratio for the entire range of abduction was 2.5:1. The greatest contribution of the scapula (1.7:1) achieved at 30 degrees-60 degrees of arm. The high accuracy and reliability of our method and the low radiation recordings suggests that digital fluoroscopy may be considered for further investigation of the scapulohumeral kinematics in both healthy and pathological shoulders.

Autoantibodies to oxidized low density lipoprotein: the relationship to low density lipoprotein fatty acid composition in diabetes.

Autoantibodies to oxidized low density lipoprotein have been shown to be an independent predictor of the progression of carotid atherosclerosis. This study examines the relationship between low density lipoprotein fatty acid composition and autoantibodies to both malondialdehyde-modified and copper-oxidized low density lipoprotein in non-diabetic patients with (n = 17), and without (n = 18), definite evidence of previous myocardial infarction. The third group were non-insulin-dependent diabetic patients with no evidence of atherosclerosis (n = 15) and the fourth group were patients with non-insulin-dependent diabetes (n = 17) who had definite evidence of previous myocardial infarction. Fatty acids were measured by gas-liquid chromatography. Antibodies to malondialdehyde-modified low density lipoprotein and copper-oxidized low density lipoprotein were determined by an ELISA method. Autoantibodies to copper-oxidized low density lipoprotein were significantly higher in the non-diabetic patients with heart disease when compared to any other group (p < 0.05). Autoantibodies to malondialdehyde-modified low density lipoprotein were significantly higher in the non-diabetic subjects with heart disease and in both diabetic groups compared to non-diabetic subjects without coronary heart disease (p < 0.05). Linoleic acid (%) in low density lipoprotein did not differ between groups groups but arachidonic acid (%) was significantly lower in both diabetic and non-diabetic patients with coronary heart disease (p < 0.05). The diabetic patients with low antibodies had 39.6 +/- 2.2% polyunsaturated fatty acids in their low density lipoprotein while diabetic patients with high antibodies had 46.7 +/- 1.2% polyunsaturates in their low density lipoprotein (p < 0.01). This study confirms the association between antibodies to oxidized low density lipoprotein and coronary heart disease and shows raised low density lipoprotein antibody levels in diabetic patients with and without demonstrable atherosclerosis. In the diabetic patients, those with high antibody levels had high polyunsaturated fatty acid levels in their LDL suggesting a possible role for dietary intervention.

Aspiration arthrography of the hip joint. Its uses and limitations in revision hip surgery.

Seventy-one patients undergoing revision hip surgery over a 5-year period from 1988 to 1993 had aspiration arthrography of the hip as a preoperative investigation. Sixteen hips were found to be infected at operation. Preoperative aspiration yielded positive cultures in 11 of these 16 hips. There was identical correlation between the organisms isolated on aspiration and during surgery. There were 5 false positive cultures from the aspirates of the remaining 55 noninfected hips. All of the hips from which a true positive culture was obtained had either clinical or radiologic evidence suggestive of infection. Aspiration arthrography does not have a major role to play as a routine investigation prior to all revision hip surgery. It is recommended that its use be reserved for those hips in which there is either clinical, hematologic, or radiologic evidence of infection.

The planovalgus rheumatoid foot--is tibialis posterior tendon rupture a factor?

The purpose of this study was to assess gross tibialis posterior tendon (TPT) integrity in a series of patients with a planovalgus foot deformity secondary to rheumatoid arthritis. This was done by means of contrast tenography. Our findings of an intact tendon in all of the seventeen patients studied suggest that complete rupture of the TPT is not the primary aetiology in the planovalgus rheumatoid foot.

The Patient Self-Determination Act. Advance directives available to Minnesota patients.

The Patient Self-Determination Act requires most health care institutions to inform patients of their right to refuse medical care and their right to provide advance direction regarding their wishes should they become incompetent. Although the PSDA does not apply to physicians, it will probably increase the demand for communication with patients on such matters. Patients will undoubtedly ask how to formulate advance directives. While physicians should make it clear that they are not providing legal advice to patients on such issues, they may wish to indicate that a guardianship and a living will are options available under Minnesota law. Additionally, as indicated above, a number of arguments exist that durable powers of attorney for health care are valid in Minnesota, as well. Physicians should familiarize themselves with living will forms and may wish to make them available to patients upon request. (Living will forms can be obtained by contacting the Minnesota Medical Association at 612/378-1875.) Patients with questions regarding durable powers of attorney should be advised to seek legal counsel.

Getting the best price from health plans. Legal pitfalls of physician cooperation.

Antitrust laws place significant limits on collective action among independent practicing physicians. The lawful options most likely to appeal to physicians include the complete merger of physician practices or the significant involvement of a physician or group in a partially integrated legitimate joint venture, such as a provider-sponsored PPO. Neither activity should be undertaken without the assistance of legal counsel. Change in the overall thrust of antitrust law is unlikely, and physicians must protect themselves from liability through careful business planning and the use of competent legal counsel.

Epithelial component of host-tumor interactions in the orthotopic site preference of a mouse mammary tumor.

Mouse mammary tumors grow preferentially upon transplantation into intact mammary glands compared to cleared mammary fat-pads. Both sites provide stroma of the orthotopic site, but the latter lacks epithelial elements. If epithelium from enzymatically dissociated normal mammary glands is added to the tumor cells prior to injection into cleared fat-pads, tumor growth is comparable to that seen in intact mammary fat-pads. The growth-enhancing effects of normal mammary cells are not duplicated by normal kidney or liver cells. These results demonstrate that epithelial-epithelial interactions, as well as stromal-epithelial interactions, are associated with the enhanced growth of mammary tumor cells transplanted into orthotopic sites. The results also suggest that enhancement of tumor growth does not require intact tissue architecture.

Spontaneous fusion between metastatic mammary tumor subpopulations.

This study describes a differential frequency of spontaneous fusion between metastatic and nonmetastatic subpopulations derived from a single mouse mammary tumor. Subpopulations 66, 66c14 (a variant of 66 which is resistant to both thioguanine and ouabain), 410.4, and 44FTO (a thioguanine-resistant, ouabain-resistant derivative of 410.4) spontaneously metastasize from subcutaneous and mammary fatpad sites. Subpopulations 168, 168FARO (a diaminopurine-resistant, ouabain-resistant derivative of 168), 67, 68H, and 410 do not. The ability of these subpopulation lines to fuse spontaneously in vitro was determined after coculturing a drug-resistant line with a wild-type line in nonselective media. After 16-20 h of coculture, cells were plated in the appropriate media to select for fusion products--either HAT (hypoxanthine, aminopterin, thymidine) plus ouabain or AA (alanosine, adenine) plus ouabain--to determine the number of colony-forming cells (fusion products) present per 10(4) cells plated. When both subpopulations of the pair in the fusion mixture were metastatic, a significantly greater number of fusion products was recovered than if one or both of the subpopulations in the fusion mixture was nonmetastatic, with one exception: line 410 readily fused with both 66c14 and 44FTO. Subline 410 was highly metastatic when originally isolated but lost its metastatic competence after a brief time in tissue culture.

Evaluation of the processing functions of a digital subtraction angiography image processor.

A large number of imaging systems for digital subtraction angiography (DSA) are now commercially available. Numerous evaluations of the performance of these systems have been reported in the literature. However systematic evaluations of the processing functions of DSA image processors have not been widely reported. Such an evaluation for one commercial system is presented in this paper. Functions evaluated include linear transformation, logarithmic transformation, integration, subtraction and temporal filtration. The observations indicate that image processing results are frequently achieved by indirect routes which compromise the fidelity of the image data.