US with extended field of view: phantom-tested accuracy of distance measurements

To evaluate the accuracy of distance measurements obtained with the extended-field-of-view (FOV) software of a commercially available ultrasonographic scanner, two custom-designed phantoms that allowed scanning of flat and curved surfaces were used. Five hundred forty measurements of various known distances in the phantoms were made by three examiners using various transducers. Although minor differences were observed between operators and transducers, 99.4% (537 of 540) of the distance measurements were accurate within plus or minus 4%. This extended-FOV technology provides accurate measurements of large objects in vitro.

ENT open access clinic: an audit of a new service

Ear, nose and throat emergencies constitute a heavy but unpredictable workload for the junior otolaryngologist. Patients are often seen in the treatment room on the ward or in the casualty department. Many patients referred as emergencies can in fact be seen the following day without detriment. This audit examined the change in treatment room workload when an open access ENT clinic was set up each weekday morning. The results demonstrate that around 75 per cent of the patients seen were suitable for waiting until the next day. The clinic was considered a success as it provided benefits for GP access, routine clinics, junior doctor teaching and concentration of aural toilet cases under expert nurse care.

Influence of low HDL on progression of coronary artery disease and response to fluvastatin therapy

BACKGROUND--Patients with coronary artery disease (CAD) commonly have low HDL cholesterol (HDL-C) and mildly elevated LDL cholesterol (LDL-C), leading to uncertainty as to whether the appropriate goal of therapy should be lowering LDL-C or raising HDL-C. METHODS AND RESULTS--Patients in the Lipoprotein and Coronary Atherosclerosis Study (LCAS) had mildly to moderately elevated LDL-C; many also had low HDL-C, providing an opportunity to compare angiographic progression and the benefits of the HMG-CoA reductase inhibitor fluvastatin in patients with low versus patients with higher HDL-C. Of the 339 patients with biochemical and angiographic data, 68 had baseline HDL-C <0.91 mmol/L (35 mg/dL), mean 0.82+/-0.06 mmol/L (31. 7+/-2.2 mg/dL), versus 1.23+/-0.29 mmol/L (47.4+/-11.2 mg/dL) in patients with baseline HDL-C >/=0.91 mmol/L. Among patients on placebo, those with low HDL-C had significantly more angiographic progression than those with higher HDL-C. Fluvastatin significantly reduced progression among low-HDL-C patients: 0.065+/-0.036 mm versus 0.274+/-0.045 mm in placebo patients (P=0.0004); respective minimum lumen diameter decreases among higher-HDL-C patients were 0. 036+/-0.021 mm and 0.083+/-0.019 mm (P=0.09). The treatment effect of fluvastatin on minimum lumen diameter change was significantly greater among low-HDL-C patients than among higher-HDL-C patients (P=0.01); among low-HDL-C patients, fluvastatin patients had improved event-free survival compared with placebo patients. CONCLUSIONS--Although the predominant lipid-modifying effect of fluvastatin is to decrease LDL-C, patients with low HDL-C received the greatest angiographic and clinical benefit.

Future of lipid-lowering trials: what else do we need to know?

Convincing clinical trial evidence shows that lipid-lowering therapy can be effective in primary and secondary prevention of coronary artery disease events. At least 2 studies indicate that this benefit extends to persons with only mild or moderate hypercholesterolemia. The benefits of lipid-lowering therapy in certain subpopulations, however, remains to be elucidated. The effects in women, African Americans, the elderly, and patients with concomitant coronary artery disease risk factors such as diabetes and hypertension are only recently being studied in large, well-designed trials. Other trials, described herein, are studying the benefits of therapy in persons with coronary artery disease and low levels of high-density lipoprotein (HDL) cholesterol (but normal or only mildly elevated total or low-density lipoprotein [LDL] cholesterol). Future trials are needed to assess prospectively the value of aggressive lipid-lowering therapy on coronary artery disease events in diabetic patients with and without coronary artery disease. New drug therapies and innovative uses for existing therapies are being developed that may have an important impact on the prevention of coronary artery disease.

Clinical diagnosis of lipid disorders

Atherosclerotic cardiovascular disease is a major health problem in the United States. In particular, coronary heart disease (CHD) is the leading cause of death in men and women in the United States, as well as in other industrialized countries. Extensive observational epidemiologic data within and between populations have strongly linked such various factors as untreated hypertension, diabetes, cigarette smoking, and lipid abnormalities to the development of CHD. With respect to lipoprotein parameters, elevated total and low-density lipoprotein cholesterol (LDL-C) and low levels of high-density lipoprotein cholesterol (HDL-C) have been strongly associated with CHD risk. Emerging evidence suggests that other lipoprotein abnormalities also are associated with premature CHD, including elevated levels of lipoprotein(a), triglyceride-rich lipoproteins such as small very-low-density lipoproteins and intermediate-density lipoproteins, small and dense LDL particles, and the magnitude of postprandial lipemia. Extensive primary and secondary clinical trial evidence has established that favorably altering dyslipidemias through diet and a variety of pharmacologic agents produces clear improvements in CHD end points. The extent of this benefit depends on the presence or absence of clinical atherosclerotic disease, as well as other CHD risk factors, and the severity of one or more lipoprotein abnormalities. CHD patients and individuals with multiple risk factors, but free of clinical CHD, derive the greatest absolute benefit from lipid treatment directed at reducing LDL-C. The dyslipidemias that impart high risk are severely elevated LDL-C (> 200 mg/dL), combined high LDL-C and low HDL-C (< 35 mg/dL), and combined hyperlipidemias (non-HDL-C > 200 mg/dL with low HDL). The purpose of this review is to aid the primary care physician in identifying these important dyslipidemias and to critically analyze the relative importance of various lipoproteins on atherosclerotic risk.

A Multicenter, Placebo-Controlled, Dose-Ranging Study of Atorvastatin

BACKGROUND: Coronary heart disease (CHD) is the number one cause of death in Western societies. Elevated levels of plasma low-density lipoprotein (LDL) cholesterol and triglycerides (TG) increase the risk for CHD. 3-Hydroxy-3-methylglutaryl conenzyme A (HMG-CoA) reductase inhibitors effectively reduce plasma cholesterol levels in patients with hypercholesterolemia. This study assesses the safety and dose-related effects of atorvastatin calcium on lipoprotein fractions in patients with LDL cholesterol levels between 160 mg/dL (4.1 mM) and 250 mg/dL (6.5 mM) or less and TG levels of 400 mg/dL (4.5 mM) or less. METHODS AND RESULTS: Sixty-five patients were enrolled in a 6-week, randomized, placebo-controlled, parallel-group study. Patients received placebo or atorvastatin 10, 20, 40, 60, or 80 mg once daily. Adjusted mean decreases in LDL cholesterol for patients receiving atorvastatin 10, 20, 40, 60, and 80 mg were 37%, 42%, 50%, 52%, and 59%, respectively, compared with a mean increase of 0.3% for patients receiving placebo; the differences between each of the atorvastatin dose groups and placebo were statistically significant (P =.0001). Total cholesterol, triglycerides, and apolipoprotein B were significantly reduced in atorvastatin groups (P =.0001). Adverse events were similar in the placebo and atorvastatin treatment groups. No patient had a serious adverse event or withdrew because of an adverse event during this study. CONCLUSIONS: Atorvastatin effectively lowered plasma LDL cholesterol, triglycerides, and apoB levels in a dose-related manner. Atorvastatin was well tolerated in hyperlipidemic patients over a 6-week period.

Long-term effects of low-density lipoprotein apheresis using an automated dextran sulfate cellulose adsorption system. Liposorber Study Group

The short-term effectiveness of low-density lipoprotein (LDL) apheresis using a dextran sulfate cellulose adsorption column technique was previously examined in a 9-center, 22-week controlled trial in 64 patients with familial hypercholesterolemia (FH) who did not adequately respond to diet and drug therapy. Forty-nine patients (40 treatment, 9 controls) subsequently received LDL apheresis procedures as part of an optional follow-up phase. This study reports on the long-term safety, lipid lowering, and clinical efficacy of LDL apheresis for the 5-year period that includes both the initial controlled study and follow-up phase. During this time, patients received a total of 3,902 treatments of which 3,314 treatments were given during the follow-up phase. Adverse events were infrequent, occurring in 142 procedures (3.6%). Immediate reduction in LDL cholesterol was 76% both in homozygotes and in heterozygotes. Patients with homozygous FH had a progressive decrease in pretreatment LDL cholesterol level along with an increase in high-density lipoprotein (HDL) cholesterol level. There was no appreciable change in pretreatment lipoprotein level over time in heterozygotes. The rate of cardiovascular events during therapy with LDL apheresis and lipid-lowering drugs was 3.5 events per 1,000 patient-months of treatment compared with 6.3 events per 1,000 patient-months for the 5 years before LDL apheresis therapy. These findings support the long-term safety and clinical efficacy of LDL apheresis in patients with heterozygous and homozygous FH who are inadequately controlled with drug therapy.

Effects of lipid lowering therapy on progression of coronary and carotid artery disease

Recent data have extended the benefit of lipid lowering therapy to patients with only mildly to moderately elevated LDL-cholesterol, which is typical of patients with coronary artery disease. Meta-analysis of clinical trials of statin therapy with similar sample sizes indicated that the LDL-cholesterol level on treatment was as good a predictor of angiographic benefit as was the percentage reduction in LDL-cholesterol. We review evidence that management of triglyceride-rich lipoproteins, HDL, fibrinogen, lipoprotein particle size, LDL-oxidation, and lipoprotein (a) may also favorably influence atherosclerotic progression. Angiographic and arterial ultrasound trials of lipid lowering therapy have demonstrated benefits on disease progression that are consistent with benefits on myocardial infarction, stroke, and death reported in larger, lengthier trials.

Epithelial stem cells

New molecular markers for epidermal stem cells have enabled their isolation both in vitro and from the epidermis lying between hair follicles. Micro-dissection experiments have localised a second population of stem cells within hair follicles. Epidermal stem cells have a patterned distribution in vivo. The patterning can be reconstituted in vitro, showing that it is generated by interactions between keratinocytes and that the differentiation of epidermal stem cells is regulated by signals from other keratinocytes. Recent evidence from transgenic mice suggests that stem cell behaviour in the gut may be regulated by similar cell-cell interactions in vivo. Candidate genes for mediating these interactions are the homologues of Drosophila cell fate patterning genes such as Notch and Wingless and the Cadherin family of cell-cell adhesion molecules. The roles of stem cells and of mutations of the Patched gene in epithelial carcinogenesis are discussed.

Effects of fluvastatin on coronary atherosclerosis in patients with mild to moderate cholesterol elevations (Lipoprotein and Coronary Atherosclerosis Study [LCAS])

Despite the potential for reduced morbidity and mortality, aggressive intervention against mild to moderate hypercholesterolemia in patients with coronary heart disease (CHD) remains controversial and infrequently practiced. Eligible patients in the 2.5-year Lipoprotein and Coronary Atherosclerosis Study were men and women aged 35 to 75 years with angiographic CHD and mean low-density lipoprotein (LDL) cholesterol of 115 to 190 mg/dl despite diet. Patients (n = 429; 19% women) were randomized to fluvastatin 20 mg twice daily or placebo. One fourth of patients were also assigned open-label adjunctive cholestyramine up to 12 g/day because prerandomization LDL cholesterol remained > or = 160 mg/dl. The primary end point, assessed by quantitative coronary angiography, was within-patient per-lesion change in minimum lumen diameter (MLD) of qualifying lesions. Across 2.5 years, mean LDL cholesterol was reduced by 23.9% in all fluvastatin patients (+/- cholestyramine) (146 to 111 mg/dl) and by 22.5% in the fluvastatin only subgroup (137 to 106 mg/dl). Primary end point analysis (340 patients) showed significantly less lesion progression in all fluvastatin versus all placebo patients, deltaMLD -0.028 versus -0.100 mm (p <0.01), and for fluvastatin alone versus placebo alone, deltaMLD -0.024 versus -0.094 mm (p <0.02). A consistent angiographic benefit with treatment was seen whether baseline LDL cholesterol was above or below 160 or 130 mg/dl. Beneficial trends with treatment were also consistently seen in clinical event rates but were not statistically significant. Thus, lipid lowering by fluvastatin in patients with mildly to moderately elevated LDL cholesterol significantly slowed CHD progression.

Effectiveness of atorvastatin for reducing low-density lipoprotein cholesterol to National Cholesterol Education Program treatment goals

Atorvastatin is a highly efficacious hydroxymethylglutaryl-coenzyme A reductase inhibitor that has been shown to reduce low-density lipoprotein cholesterol by 40% to 60%. Monotherapy with atorvastatin (10 to 80 mg/day) is well-tolerated, convenient, and appears to be effective for achieving National Cholesterol Education Program treatment goals in most patients, regardless of risk status.

Physician education in hyperlipidemia management: the impact on collaboration

Collaboration of health care professionals is likely beneficial in modifying patient behavior in the treatment of hyperlipidemia. The purpose of this study was to determine whether limited instruction and demonstration of collaborative management of hyperlipidemia in a continuing medical education (CME) would change physicians' office practices, as determined 1 year later by questionnaire. Collaborative practice was defined as physicians working with other allied health care professionals as a team to increase patients' medication compliance and other behavioral outcomes. A 19-credit hour CME Lipid Disorders Training Program (LDTP) was offered emphasizing the collaborative approach to hyperlipidemia patient management. Physicians (n = 196) were surveyed 1 year after LDTP. The response rate was 52.5%, nonrespondents were similar in locations. About 51% of respondents reported increased collaborative practice; of these respondents, 68% reported saving time, 78% reported improved patient outcomes, 76% improved office efficiency, and 90% increased patient satisfaction. According to self-reporting by these physicians, increased collaboration practices after attending the LDTP course led to improved patient outcomes.

Functional significance of CD9 association with beta 1 integrins in human epidermal keratinocytes

CD9 is a member of the tetraspan (TM4) family of proteins and is abundantly expressed in the epidermis. As CD9 forms complexes with beta 1 integrins and the integrins are known to regulate keratinocyte behaviour, we investigated CD9 expression and function in human epidermal keratinocytes. CD9 was present in all the living layers of the epidermis, whereas the beta 1 integrins were largely confined to the basal layer; the same relative distribution was found in stratified cultures of keratinocytes. There was extensive co-localisation of CD9 and beta 1 integrins on microvilli and at cell-cell borders of basal keratinocytes; however, in contrast to the integrins, CD9 was not found in focal adhesions. CD9 was detected in beta 1 integrin immunoprecipitates and also in immunoprecipitates of CD44 and syndecan, but not of cadherins. CD9 was associated with alpha 3 beta 1 but not alpha 5 beta 1; small amounts of CD9 also co-immunoprecipitated with antibodies to alpha 2 beta 1 and alpha 6 beta 4. Antibodies to CD9 did not affect the proportion of keratinocytes that adhered to laminin 1, type IV collagen and fibronectin, but did inhibit motility of keratinocytes on tissue culture plastic. Like antibodies to the beta 1 integrin subunit, anti-CD9 inhibited suspension-induced terminal differentiation. These results suggest that CD9 may play a role in regulating keartinocyte motility and differentiation.

Isolation and characterization of human epidermal stem cells

1. The keratinocytes in human epidermis are constantly turned over and replaced by a population of stem cells located in the basal epidermal layer. Until recently there were no markers allowing the isolation of viable epidermal stem cells. However, it has now been shown that epidermal stem cells can be isolated both in vitro and direct from the epidermis as they express high levels of functional beta 1 integrin family receptors for extracellular matrix proteins. 2. The evidence for integrins as stem cell markers and the insights that have been gained into stem cell behaviour are reviewed.

Effect of gemfibrozil on levels of lipoprotein[a] in type II hyperlipoproteinemic subjects

Plasma lipoprotein[a] (Lp[a]) levels are highly correlated with angiographically demonstrable coronary heart disease, and elevated Lp[a] is an independent risk factor for atherosclerosis. Previous studies have provided evidence that the levels of Lp[a] and triglyceride are related, suggesting that Lp[a] might be altered by gemfibrozil, a drug well known for its efficacy in reducing plasma triglycerides. Accordingly, 18 type IIa and 16 type IIb hyperlipoproteinemic males aged 35-58 were treated for 3 months with 600 mg of gemfibrozil twice daily. The efficacy of the drug in altering lipid and lipoprotein levels was different in the two type groups. In type IIa and IIb subjects the respective changes in median levels were: total cholesterol, -7.5 and -8.5% triglycerides, -35.6 and -54.4%; HDL-cholesterol, +9.0 and +11.0%; and Lp[a], -17.2 and +6.1%. Before and after gemfibrozil treatment, 7 type IIa and 10 type IIB subjects were given a 100 g/2 m2 oral-fat load; triglycerides and Lp[a] were measured post-prandially at 0, 2, 4, 6, 8, and 10 h. The differences between before- and after-gemfibrozil post-prandial curve integrated areas (PPCIA) were compared for triglycerides and Lp[a]. The changes in median PPCIA for triglycerides in types IIa and IIB were -54% and -53%, and for Lp[a] were -8% and +8%, respectively. These results indicate i) that the levels of Lp[a] are about 2 times higher in type IIa than IIb subjects, and ii) that although gemfibrozil elicits a rather uniform decrease in fasting and post-prandial triglyceride levels in type IIa and IIb patients, the drug causes heterogeneous changes in Lp[a], suggesting that different metabolic mechanisms may be dominant in subjects showing opposing effects.

Comparison of a microtitration plate ELISA with a standard cultural procedure for the detection of Salmonella spp. in chicken

A rapid antibody-capture enzyme-linked immunosorbent assay (ELISA) detecting a wide range of Salmonella serotypes and employing only one culture stage was used to analyze the giblets and body cavity rinsings from frozen chickens. The results from the ELISA were compared with those obtained using a standard cultural procedure in current use in two laboratories, Norwich (N) and Ipswich (I), of the Public Health Laboratory Service (PHLS) in the UK. ELISAs were carried out on the same samples at each of two PHLS laboratories and at the Institute of Food Research with good agreement (94% and 90%). When compared with the cultural method there was 80% and 70% agreement with the ELISA with the PHLS(N) and PHLS(I) samples. The ELISA appeared to have a false-positive rate of 17% (samples from PHLS(N)) but on reculture of the "negative" samples this rate fell to 7%. The false-negative rate for the ELISA was 26% (samples from PHLS(N)) which appeared to be due to insufficient growth of the Salmonella spp. in the single cultural step employed in the ELISA rather than lack of recognition by the antibodies. The problem of false negatives with the cultural method is also discussed. These results are comparable to previously published studies relating immunoassays and the conventional procedure for Salmonella detection when analyzing similar samples. Suggestions are made as to how further increases in ELISA efficiency might be brought about.

Treatment of Dyslipidemias

OBJECTIVE

To summarize recommended treatment strategies for various dyslipidemias.

METHODS

The basic pathways of lipoprotein metabolism are reviewed, and the potential for interventional alterations to correct specific dyslipidemias is outlined. Guidelines for treatment based on published clinical trials, including the consensus report of the National Cholesterol Education Program, are discussed.

RESULTS

The nonpharmacologic options of diet and exercise are important elements in the treatment of dyslipidemias. In most patients, a reduced dietary intake of fat (particularly saturated fat) should be maintained for 3 months before drug therapy is initiated. The various mechanisms of action of the bile acid resins, niacin, hydroxy-methylglutaryl-coenzyme A reductase inhibitors, and fibric acid derivatives are described, and their roles in monotherapy or combination therapy for hypercholesterolemia, combined hyperlipidemia, and hypertriglyceridemia are examined.

CONCLUSION

With an understanding of the metabolic pathways responsible for the production and removal of lipoproteins and an overview of results of previous pharmacologic interventions, clinicians can optimize lipid-lowering treatment in individual patients with dyslipidemia.

Trials of lipid-lowering therapy in primary prevention of coronary heart disease

The effectiveness of lipid-regulating therapy in the primary prevention of coronary heart disease requires further investigation. The only data available are from trials conducted before the advent of more potent lipid-regulating agents, but several large trials currently in progress are expected to provide valuable evidence about the role of lipid-regulating intervention in primary prevention.