Age-associated rapid and Stat6-independent IL-4 production by NK1-CD4+8- thymus T lymphocytes

The source of IL-4 required for priming naive T cells into IL-4-secreting effectors has not been clearly identified. Here we show that upon TCR stimulation, thymus NK1-CD4+8- T cells produced IL-4, the magnitude of which was inversely correlated with age. This IL-4 production response by Th2-prone BALB/c mice was approximately 9-fold that of Th1-prone C57BL/10 mice. More than 90% of activated NK1-CD4+8- thymocytes did not use the invariant V alpha 14-J alpha 281 chain characteristic of typical CD1-restricted NK1+CD4+ T cells. Stat6-null NK1-CD4+8- thymocytes produced bioactive IL-4, with induction of IL-4 mRNA expression within 1 h of stimulation. Our results support the possibility that TCR repertoire-diverse conventional NK1-CD4+ T cells are a potential IL-4 source for directing naive T cells toward Th2/type 2 CD8+ T cell (Tc2) effector development.

Identification of Cancer Antigens in Breast Cancer by the SEREX Expression Cloning Method

Enormous strides in cancer immunology have been made during the past decade. This is largely due to the development of methodologies capable of defining the antigenic targets on cancer cells that elicit a host immune response. The molecular cloning of antigens recognized by cytotoxic T cells by Boon and his colleagues has provided a growing list of tumor antigens, particularly for melanoma, that allows detailed monitoring of T cell responses to these antigens and offers promising targets for cancer vaccine development. An alternative new method, SEREX, for the serological identification of cancer antigens has been developed by Pfreundschuh and his colleagues. SEREX can be applied to all types of cancer including breast cancer that have been unapproachable by using cytotoxic T cells and thus offers an opportunity to define a vast range of cancer antigens. Toward thedevelopment of a vaccine for breast cancer, we have begun using SEREX to study breast cancer and have identified a few promising cancer antigens. Each antigen is now being critically evaluated as a possible vaccine target.

Humoral immune responses of cancer patients against "Cancer-Testis" antigen NY-ESO-1: correlation with clinical events

Humoral immune responses against the "Cancer-Testis" (CT) antigen NY-ESO-1 are frequently observed in patients with NY-ESO-1 expressing tumors. This is in contrast to other known tumor antigens (TA) defined by antibody or cytotoxic T cell (CTL) reactivity, i.e., MAGE-1, MAGE-3, SSX2, Melan A, and tyrosinase. No NY-ESO-1 antibody has been detected in healthy controls and patients with NY-ESO-1 negative tumors. In this study, we have assessed the NY-ESO-1 serum antibody response in patients with NY-ESO-1 positive tumors of different histological types and stages using Western blotting and an ELISA. Of the 12 patients analyzed, 10 had demonstrable NY-ESO-1 antibodies at the start of the study. All patients were followed for changes in NY-ESO-1 antibody titers during the course of tumor treatment and clinical evolution. In 4 patients, an increase of NY-ESO-1 antibody titer was observed with progression of disease or extensive tumor necrosis under treatment. One patient showed a stable NY-ESO-1 antibody titer over 3 years along with gradual regression of a large tumor mass. In 5 patients, a decrease of NY-ESO-1 antibody was detected: in 1 patient after curative tumor resection, in 3 patients with partial regression of metastatic disease under chemo- and immunotherapy, and in another patient with a NY-ESO-1 negative tumor relapse. Our results indicate that the induction and maintenance of NY-ESO-1 antibody is dependent on the presence of NY-ESO-1 expressing tumors. Furthermore, changes in NY-ESO-1 antibody titers correlate with the evolution of NY-ESO-1 positive disease.

Humoral immune responses of cancer patients against "Cancer-Testis" antigen NY-ESO-1: correlation with clinical events

Humoral immune responses against the "Cancer-Testis" (CT) antigen NY-ESO-1 are frequently observed in patients with NY-ESO-1 expressing tumors. This is in contrast to other known tumor antigens (TA) defined by antibody or cytotoxic T cell (CTL) reactivity, i.e., MAGE-1, MAGE-3, SSX2, Melan A, and tyrosinase. No NY-ESO-1 antibody has been detected in healthy controls and patients with NY-ESO-1 negative tumors. In this study, we have assessed the NY-ESO-1 serum antibody response in patients with NY-ESO-1 positive tumors of different histological types and stages using Western blotting and an ELISA. Of the 12 patients analyzed, 10 had demonstrable NY-ESO-1 antibodies at the start of the study. All patients were followed for changes in NY-ESO-1 antibody titers during the course of tumor treatment and clinical evolution. In 4 patients, an increase of NY-ESO-1 antibody titer was observed with progression of disease or extensive tumor necrosis under treatment. One patient showed a stable NY-ESO-1 antibody titer over 3 years along with gradual regression of a large tumor mass. In 5 patients, a decrease of NY-ESO-1 antibody was detected: in 1 patient after curative tumor resection, in 3 patients with partial regression of metastatic disease under chemo- and immunotherapy, and in another patient with a NY-ESO-1 negative tumor relapse. Our results indicate that the induction and maintenance of NY-ESO-1 antibody is dependent on the presence of NY-ESO-1 expressing tumors. Furthermore, changes in NY-ESO-1 antibody titers correlate with the evolution of NY-ESO-1 positive disease.

Nutritional deficiencies in a patient with glycogen storage disease type Ib

The current mainstay of treatment in glycogen storage disease type I (GSD I) is dietary management that includes providing a frequent source of glucose to prevent hypoglycaemia. To ensure compliance, routine follow-up by a health care team, including a dietitian, experienced in the treatment of GSD is necessary. We describe an adolescent patient with GSD Ib in good metabolic control who was admitted with a 3-month history of weakness, depression, vomiting, decreased appetite and a 11.4-kg weight loss. He had a recent onset of unsteady gait, inability to write, and sore mouth. After an extensive work-up, the patient was found to have vitamin B12, folate, iron and other nutritional deficiencies, which explained his symptoms. The patient improved within 72 h of initiation of total parenteral nutrition and therapeutic doses of deficient micronutrients, with a complete recovery in 2 months. Dietary restrictions, dependence on non-food products (e.g. cornstarch in GSD I), and social and developmental issues place individuals with metabolic disorders at a high risk for developing an array of nutritional deficiencies. This case highlights the importance of both close follow-up of the metabolic control and close monitoring of growth and nutritional intake in individuals with inborn errors of metabolism. This case also illustrates the importance of daily supplementation with appropriate multivitamins, calcium and other minerals needed to meet the Recommended Dietary Allowances (RDAs) in these patients.

Differences in cervical cancer mortality among black and white women

OBJECTIVE

To determine whether stage of disease and treatment patterns account for mortality differences between black and white women with cervical cancer.

METHODS

Using data obtained from the Surveillance, Epidemiology, and End Results (SEER) Program for 1988-1994, we determined the associations between race and stage, and race and treatment. Racial differences in survival for up to 7 years of follow-up were adjusted for age, marital status, SEER location, International Federation of Gynecology and Obstetrics (FIGO) stage of disease, lymph node status, grade, histology, and treatment.

RESULTS

Cumulative mortality was 36% (366 deaths in 1029 women) for black women and 24% (1215 deaths in 5021 women) for white women; unadjusted hazard ratio was 1.60 (95% confidence interval [CI] 1.43, 1.80). Black women were more likely to present with advanced disease than white women (43.8% compared with 34.8%). In a model adjusting for demographics and FIGO stage, the hazard ratio for black women compared with white women decreased to 1.35 (95% CI 1.19, 1.54). Treatment varied by race, with black women receiving surgery less often (33.5% compared with 48.2%, respectively) and radiation therapy more often (35.3% and 25.2%, respectively) than white women. In a comprehensive model including demographic factors, FIGO stage, other tumor characteristics, and treatment, the adjusted hazard ratio for mortality remained high for black women at 1.30 (95% CI 1.14, 1.48).

CONCLUSION

Race remains an independent predictor of cervical cancer survival after accounting for age, stage of disease, treatment patterns, and other factors. Future studies should assess racial differences in clinical severity of disease, comorbidity, and socioeconomic status.

Coronary artery aneurysms: A 25-patient study

Coronary artery aneurysm is a rare disorder, characterized by abnormal dilatation of a localized portion or diffuse segments of the coronary artery. We studied clinical demographics, catheterization findings, and clinical outcomes in an Asian patient cohort with documented coronary artery aneurysms. Compared to a Caucasian adult population, our patient cohort had a lower incidence of coronary artery aneurysm (0.25% vs. 2.6%), and more patients with nonobstructive coronary artery aneurysms (70%); age, gender, and coronary distribution were comparable. The initial presentation of myocardial infarction occurred in five patients (5/17, 30%) with nonobstructive coronary artery aneurysms; however, none who were receiving preventive medications consisting of anticoagulant and antiplatelet agents subsequently developed myocardial infarction. We conclude that the incidence of coronary artery aneurysms with or without associated significant coronary stenosis seems to be lower in the Asian population. In contrast, the incidence of nonobstructive coronary artery aneurysms is considerably high and should not be thought of as a relatively benign disease entity if not treated with preventive medications. Rheumatoid arthritis-related vasculitis might be a cause of coronary artery aneurysm. Surgical intervention is based on the severity of coronary artery stenosis. The result of medical treatment has been compatible with long-term survival. Cathet. Cardiovasc. Intervent. 48:31-38, 1999.

Trp64Arg polymorphism of the beta 3-adrenergic receptor gene is associated with increased plasma leptin levels in obese Chinese women

BACKGROUND

beta 3-Adrenergic receptors are predominantly expressed in the fat cells of visceral adipose tissue in humans. They mediate catecholamine-induced lipolysis and thermogenesis of adipose tissue, which are important for the regulation of energy expenditure and, therefore, body weight. Recently, a Trp64Arg polymorphism of the beta 3-adrenergic receptor gene was reported to be associated with obesity and obesity-related metabolic complications in some ethnic populations. Leptin, a protein secreted by adipocytes, is proposed as a signal linkage between the central nervous system and peripheral fat storage. It has been shown in rodents that leptin may activate the sympathetic nervous system and, thus, beta 3-adrenergic receptors in adipose tissue. However, little is known about the relationship between the Trp64Arg polymorphism and plasma leptin in humans.

METHODS

To determine the effects of the beta 3-adrenergic receptor gene Trp64Arg mutation on anthropometric measures, metabolic parameters and plasma leptin levels, 188 premenopausal Chinese women (mean age +/- standard deviation, 32 +/- 10 years) with body mass index (BMI) between 16.1 and 59.8 kg/m2 were investigated. Trp64Arg polymorphism was determined by DNA analysis, body fat mass by bioelectric impedance analysis and plasma leptin by radioimmunoassay.

RESULTS

Trp64Arg allele frequency was 15% in this population and there was no homozygous Arg64Arg mutant. When the subjects were divided into three groups based on BMI values (BMI < 22.2, n = 60; 22.2 < or = BMI < or = 29.5, n = 63; BMI > 29.5 kg/m2, n = 65), there was no difference in Trp64Arg allele frequency (16% vs 11% vs 18%, p = 0.149). Across the three groups, plasma leptin correlated positively with BMI (r = 0.843, p < 0.0001) and total fat mass (r = 0.824, p < 0.0001). Within each BMI tertile, the waist to hip ratio, fat mass, plasma lipids, glucose and insulin were relatively similar between Trp64Trp homozygotes and Trp64Arg heterozygotes. However, Trp64Arg heterozygotes had higher plasma leptin levels than Trp64Trp homozygotes (35.9 +/- 11.0 vs 30.0 +/- 12.8 ng/ml, p = 0.0023) in those with BMI above 29.5 kg/m2, a difference which remained after adjustment for body fat mass (p = 0.024).

CONCLUSIONS

Trp64Arg polymorphism of the beta 3-adrenergic receptor gene is not associated with obesity in Chinese women. Plasma leptin concentrations correlate well with BMI and total fat mass. For obese Chinese women, the Trp64Arg genotype of the beta 3-adrenergic receptor gene may contribute to an increased plasma leptin level.

The putative glucose 6-phosphate translocase gene is mutated in essentially all cases of glycogen storage disease type I non-a

The purpose of this work was to test the hypothesis that mutations in the putative glucose 6-phosphate translocase gene would account for most of the cases of GSD I that are not explained by mutations in the phosphohydrolase gene, ie that are not type Ia. Twenty-three additional families diagnosed as having GSD I non-a (GSDIb, Ic or Id) have now been analysed. The 9exons of the gene were amplified by PCR and mutations searched both by SSCP and heteroduplex analysis. Except for one family in which only one mutation was found, all patients had two allelic mutations in the gene encoding the putative glucose 6-phosphate translocase. Sixteen of the mutations are new and they are all predicted to lead to non-functional proteins. All investigated patients had some degree of neutropenia or neutrophil dysfunction and the clinical phenotype of the four new patients who had been diagnosed as GSD Ic and the one diagnosed as GSD Id was no different from the GSD Ib patients. Since these patients, and the four type Ic patients from two families previously studied, shared several mutations with GSD Ib patients, we conclude that their basic defect is in the putative glucose 6-phosphate translocase and that they should be reclassified as GSD Ib. Isolated defects in microsomal Pi transporter or in microsomal glucose transporter must be very rare or have phenotypes that are not recognised as GSD I, so that in practice there are only two subtypes of GSD I (GSD Ia and GSD Ib).

Prenatal diagnosis of glycogen storage disease type IV using PCR-based DNA mutation analysis

Deficiency of glycogen branching enzyme activity causes glycogen storage disease type IV (GSD-IV). Clinically, GSD-IV has variable clinical presentations ranging from a fatal neonatal neuromuscular disease, to a progressive liver cirrhosis form, and to a milder liver disease without progression. Current methods for prenatal and postnatal diagnosis are based on an indirect method of measuring the enzyme activity, which has a limited sensitivity and cannot be used to distinguish patients with these variable clinical phenotypes. In this study, a GSD-IV family with a non-progressive hepatic form of the disease requested prenatal diagnosis. Determination of the branching enzyme activity in cultivated amniocytes showed 20 per cent residual activity overlapping with the level detected in the heterozygotes. Mutation analysis revealed that the fetus carried two mutant alleles, L224P and Y329S, the same as the proband of this family. The fetus was predicted to be affected and postnatally his clinical presentation is consistent with the diagnosis. We conclude that DNA mutation analysis should be used in the prenatal diagnosis of GSD-IV, especially in the situation of high residual enzyme activity.

High plasma leptin concentrations in hypertensive men but not in hypertensive women

OBJECTIVE

Previous studies on humans have reported higher leptin levels in women than in men, independent of body fat, and leptin has been correlated with insulin resistance in men but not in women. Since insulin resistance is thought to play a role in raising blood pressure, we investigated sex differences in leptin concentrations between hypertensive and normotensive individuals.

METHODS

Ninety-two nondiabetic hypertensive patients (48 men and 44 women) and 92 age, body mass index (BMI)-matched normotensive control individuals were studied. Fasting plasma glucose, insulin, leptin and lipoprotein concentrations, glucose and insulin responses to 75 g oral glucose tolerance test (OGTT) and insulin suppression tests were determined.

RESULTS

Fasting plasma leptin concentrations were higher in hypertensive men than in normotensive men (5.1 +/- 0.5 versus 3.9 +/- 0.4 ng/ml, P = 0.015). However, fasting plasma leptin concentrations were not significantly different between hypertensive and normotensive women (11.8 +/- 1.0 versus 10.9 +/- 1.0 ng/ml, P = 0.440). Fasting plasma leptin concentrations showed good correlation with BMI, body fat, fasting plasma insulin concentrations, and insulin area to OGTT in both men and women (all P < 0.001). However, fasting plasma leptin concentrations were related to steady-state plasma glucose (SSPG) concentrations, a measure of insulin sensitivity by insulin suppression test, in men only (P < 0.001). After adjustment for body fat amount, age and duration of hypertension, fasting plasma leptin levels still correlated significantly with SSPG concentrations in men. These four variables together accounted for a 67.9% variation in fasting plasma leptin levels in men. In women, body fat amount was the only significant determinant for plasma leptin levels. These four variables accounted for a 78.2% variation in plasma leptin levels in women.

CONCLUSIONS

Our study confirmed a sex difference in leptin levels both in hypertensive and normotensive subjects. Higher plasma leptin concentrations in hypertensive men but not in hypertensive women when compared with normotensive control individuals was also demonstrated. These observations are consistent with the findings that plasma leptin is correlated with insulin sensitivity in men but not in women. Further studies are needed to understand the causes and consequences of sex effects on leptin in blood pressure regulation.

Evaluation of arterial compliance in patients with carotid arterial atherosclerosis

BACKGROUND

High-resolution peripheral vascular sonography has the capability to determine vessel compliance. A number of factors affect compliance in humans, including age, hypertension and atherosclerosis. However, compliance in patients with coronary artery disease (CAD) combined with carotid artery lesions has not been well studied. The objectives of this study were: 1) to determine whether carotid artery compliance is reduced in patients with CAD and carotid artery lesions, and 2) to determine whether decreased arterial compliance is related to an abnormality in vascular wall structure.

METHODS

The study participants included 12 patients with CAD and carotid artery disease (group III), 13 patients with CAD only (group II) and 13 age-matched normal subjects who served as controls (group I). High-resolution peripheral vascular ultrasonography was performed to directly visualize the common carotid artery and to measure its diameter and wall thickness. Carotid artery elastic properties were determined relative to arterial diameter and pressure generated within the heart.

RESULTS

Carotid artery walls were thicker in Group II and III patients than in normal subjects (1.49 +/- 0.03 mm, 1.98 +/- 0.04 mm, vs 1.22 +/- 0.03 mm, p < 0.05 and p < 0.01). There were significant differences in wall thickness between subgroups of CAD patients (p < 0.01). Carotid distensibility was lower (21.8 +/- 1.2 x 10(-6).N-1.m2, 14.8 +/- 1.7 x 10(-6).N-1.m2, vs 25.6 +/- 1.5 x 10(-6).N-1.m2; p < 0.05 and p < 0.01) and Young's modulus of elasticity was higher (3.12 +/- 0.43 x 10(5).Nm-2, 4.18 +/- 0.30 x 10(5).Nm-2, vs 2.34 +/- 0.23 x 10(5).Nm-2; p < 0.05 and p < 0.01) in group II and III patients than in normal subjects. These two indices of carotid artery compliance also differed between subgroups of CAD (p < 0.01). Increased wall thickness may occur secondary to changes in the architectural structure of the vessel wall, and these atherosclerotic changes lead to decreased compliance of arteries.

CONCLUSION

The mechanical properties of the carotid arteries provide reliable information regarding changes caused by atherosclerosis.

Systemic correction of the muscle disorder glycogen storage disease type II after hepatic targeting of a modified adenovirus vector encoding human acid-alpha-glucosidase

This report demonstrates that a single intravenous administration of a gene therapy vector can potentially result in the correction of all affected muscles in a mouse model of a human genetic muscle disease. These results were achieved by capitalizing both on the positive attributes of modified adenovirus-based vectoring systems and receptor-mediated lysosomal targeting of enzymes. The muscle disease treated, glycogen storage disease type II, is a lysosomal storage disorder that manifests as a progressive myopathy, secondary to massive glycogen accumulations in the skeletal and/or cardiac muscles of affected individuals. We demonstrated that a single intravenous administration of a modified Ad vector encoding human acid alpha-glucosidase (GAA) resulted in efficient hepatic transduction and secretion of high levels of the precursor GAA proenzyme into the plasma of treated animals. Subsequently, systemic distribution and uptake of the proenzyme into the skeletal and cardiac muscles of the GAA-knockout mouse was confirmed. As a result, systemic decreases (and correction) of the glycogen accumulations in a variety of muscle tissues was demonstrated. This model can potentially be expanded to include the treatment of other lysosomal enzyme disorders. Lessons learned from systemic genetic therapy of muscle disorders also should have implications for other muscle diseases, such as the muscular dystrophies.

Seborrheic keratosis of conjunctiva simulating a malignant melanoma: an immunocytochemical study with impression cytology

OBJECTIVE

Seborrheic keratosis on the conjunctiva appears to have never been reported in the literature. The authors report here a well-documented case of seborrheic keratosis of conjunctiva clinically simulating a malignant melanoma.

DESIGN

Case report.

METHODS

A 66-year-old man presented with a juxtalimbal pigmented tumor involving the temporal conjunctiva of his left eye. Because of the rapid enlargement of the mass within a period of 5 months, a clinical diagnosis of malignant melanoma was made. Cytopathologic examinations were performed by impression cytology before the patient underwent a wide en-block excision of the tumor.

MAIN OUTCOME MEASURES

Cytologic features were studied by impression cytology with periodic acid-Schiff-Papanicolaou stain. Immunochemical characteristics of tumor cells were studied by immunochemical stain of cytokeratin and HMB-45. Tumor morphology was observed by histopathologic examination.

RESULTS

Impression cytology disclosed basaloid cells intermixing with squamoid cells, and these cells demonstrated positive immunoreactivity to cytokeratin and no reactivity to HMB-45. Histopathologic examination of the tumor specimen established the diagnosis of seborrheic keratosis, and the results of immunohistochemical staining were consistent with those of the impression cytology with immunocytochemical staining.

CONCLUSION

The authors describe the first case report of conjunctival seborrheic keratosis and present its immunocytochemical and immunohistochemical characteristics. Such a benign lesion can clinically mimic a malignant melanoma.

Gender differences in relation to leptin concentration and insulin sensitivity in nondiabetic Chinese subjects

OBJECTIVE

To investigate the relationship between fasting plasma leptin concentrations and insulin resistance in Chinese men and women.

DESIGN

Cross-sectional study design.

SUBJECTS

Ninety-six nondiabetic Chinese (51 men and 45 women) with body mass index (BMI) between 18.4-35.8 kg/m2 were studied.

MEASUREMENTS

Plasma glucose and insulin concentrations were measured every 30 min for 2 h after a 75 g oral glucose load. The degree of insulin resistance was assessed using a modified insulin suppression test. Plasma leptin values were determined by radioimmunoassay.

RESULTS

Fasting plasma glucose, glucose areas, fasting insulin, insulin areas, most of the lipoprotein concentrations and steady state plasma glucose (SSPG) concentrations were relatively similar between men and women. Despite the fact that men had higher BMI values (26.1 +/- 0.5 vs 24.7 +/- 0.5 kg/m2, P < 0.05), fasting plasma leptin concentrations were significantly lower in men than in women (4.9 +/- 0.5 vs 9.0 +/- 0.8 ng/ml, P < 0.001). Fasting leptin values were positively related to SSPG concentrations by simple correlation analysis in both sexes. However, this relationship persisted in men (r = 0.513, P < 0.01) but not in women (r = 0.119, P = NS) after adjustment for BMI. Multiple regression analysis showed that SSPG concentrations, BMI, glucose and insulin responses together accounted for 62.5% and 52.2% of the variation in plasma leptin concentrations in Chinese men and women respectively.

CONCLUSION

Fasting plasma leptin concentrations were lower in Chinese men than in Chinese women despite the higher BMI observed in men. After adjustment for BMI, plasma leptin values correlated with the degree of insulin resistance in men but not in women.

Comparing AMI mortality among hospitals in patients 65 years of age and older: evaluating methods of risk adjustment

BACKGROUND

Interest in the reporting of risk-adjusted outcomes for patients with acute myocardial infarction is growing. A useful risk-adjustment model must balance parsimony and ease of data collection with predictive ability.

METHODS AND RESULTS

From our analysis of 82 359 patients >/=65 years of age admitted with acute myocardial infarction to 2401 hospitals, we derived a parsimonious model that predicts 30-day mortality. The model was validated on a similar group of 78 699 patients from 2386 hospitals. Of the 73 candidate predictor variables examined, 7 variables describing patient characteristics on arrival were selected for inclusion in the final model: age, cardiac arrest, anterior or lateral location of myocardial infarction, systolic blood pressure, white blood cell count, serum creatinine, and congestive heart failure. The area under the receiver-operating characteristic curve for the final model was 0.77 in the derivation cohort and 0.77 in the validation cohort. The rankings of hospitals by performance (in deciles) with this model were most similar to a comprehensive 27-variable model based on medical chart review and least similar to models based on administrative billing codes.

CONCLUSIONS

A simple 7-variable risk model performs as well as more complex models in comparing hospital outcomes for acute myocardial infarction. Although there is a continuing need to improve methods of risk adjustment, our results provide a basis for hospitals to develop a simple approach to compare outcomes.

Quality of care for patients hospitalized with heart failure at academic medical centers

BACKGROUND

The purpose of this study was to determine the standard of care provided by academic medical centers for the management of congestive heart failure (CHF).

METHODS AND RESULTS

The standard of care was estimated by assessing adherence to the treatment guidelines published by the US Agency for Health Care Policy and Research among 522 patients hospitalized at 7 university hospitals with a diagnosis of CHF. Data were abstracted by retrospective chart review. Of the 522 patients analyzed, 435 (83%) had a left ventricular ejection fraction (LVEF) measured or documented. Among these patients, 192 were considered "ideal" candidates for angiotensin-converting enzyme (ACE) inhibitor therapy (ie, with systolic dysfunction [LVEF <40%] and no contraindications to ACE inhibitors). In this cohort of "ideal" candidates, 138 (72%) were receiving ACE inhibitors at hospital discharge, including 60 (44%) who were prescribed doses recommended in large clinical trials. Compliance with patient education guidelines was assessed in all 487 patients who were alive at the time of discharge. Of these patients, 365 (75%) received dietary counseling, 404 (83%) were educated about exercise, 54 (11%) were instructed to follow daily weights, and 468 (96%) were counseled regarding medication compliance. Among the 87 smokers who were alive at time of discharge, 8 (9%) had documented advice to quit smoking.

CONCLUSIONS

This study indicates that academic medical centers performed fairly well on the assessment of LVEF, the prescription of ACE inhibitors at discharge, and on education regarding diet, exercise, and compliance with medications. However, the results suggest opportunities for improvement in ACE inhibitor dosing and patient education regarding the importance of monitoring daily weights and smoking cessation.

Risk factors for heart failure in the elderly: a prospective community-based study

PURPOSE

The risk factors for the development of heart failure are not clearly defined, particularly for older adults. We undertook the current investigation to examine the associations of traditional cardiovascular risk factors, comorbidity, and psychosocial factors with the risk of heart failure during 10 years of follow-up in a community-based elderly population.

SUBJECTS AND METHODS

We evaluated 1,749 subjects, 65 years of age or older, free of heart failure, myocardial infarction, and angina at baseline, who were participating in the New Haven, Connecticut cohort of the Established Population for Epidemiologic Studies of the Elderly program. Cox proportional hazards regression models were used to determine risk ratios (RR) and 95% confidence intervals (CI).

RESULTS

During 13,811 person-years of follow-up, 173 subjects developed incident heart failure, as confirmed by chart review. Five factors were independent predictors of heart failure: male sex (RR = 1.7; CI, 1.3 to 2.4), older age (RR = 1.9; CI, 1.3 to 2.7 for age 75 to 84 years, RR = 3.0; CI, 1.7 to 5.5 for age 85 years and older, compared with < or = 74 years), diabetes (RR = 2.9; CI, 2.0 to 4.3), pulse pressure > or = 70 mm Hg (RR = 2.3; CI, 1.3 to 4.3, compared with <50 mm Hg), and body mass index > or = 28 kg/m2 (RR = 1.6; CI, 1.0 to 2.4, compared with <24 kg/ m2). Myocardial infarction occurred during follow-up in 8% of the cohort and was also an important predictor of heart failure (RR = 21; CI, 15 to 31).

CONCLUSIONS

Age and traditional cardiovascular risk factors are associated with the development of heart failure in the elderly. Preventive strategies should focus on the management of diabetes, blood pressure, and weight, in addition to the prevention and management of myocardial infarction.

Variations in and correlates of length of stay in academic hospitals among patients with heart failure resulting from systolic dysfunction

OBJECTIVE

Given the high cost of caring for patients with congestive heart failure, there are strong incentives to decrease hospital costs by shortening length of hospital stay. We sought to identify factors associated with length of stay among patients admitted for the treatment of heart failure resulting from systolic dysfunction.

STUDY DESIGN

Retrospective cohort study.

METHODS

We examined data from patients with a principal discharge diagnosis of congestive heart failure who had been admitted to 1 of the 49 academic hospitals across the United States that participated in the CHF Benchmark Project, a large collaborative quality improvement project coordinated by the University HealthSystem Consortium. Patients were discharged between January 1 and June 30, 1996. We obtained patient characteristics and hospitalization data by retrospectively reviewing medical records. We used linear regression models to identify major determinants of length of stay.

RESULTS

Among the 1046 patients eligible for the study, 59% were women, 55% were white, and 58% were aged 65 years or older. Adjusting for patient demographic and admission clinical characteristics, the mean length of stay was 4.9 +/- 0.9 days. Length of stay varied significantly among hospitals, even after adjusting for differences in patient characteristics. In multivariate regression models, factors that were independently associated with a significantly longer length of stay were prior renal failure, peripheral edema, atrial fibrillation, hyponatremia, urinary catheter on admission, initiation of an antiarrhythmic or warfarin, and major complications. Patient characteristics and hospital events combined explained 16% of the variation in the length of stay. Adjusting for the individual hospitals explained an additional 10% of the variation in the length of stay.

CONCLUSIONS

Although a number of patient and hospitalization factors were associated with length of stay in patients with congestive heart failure resulting from systolic dysfunction, much unexplained variation remained. Clinical factors alone explained about 50% more variation than did factors specific to the individual hospitals.

Lack of association between genetic variation in the beta3-adrenergic receptor gene and insulin resistance in patients with coronary heart disease

The beta-adrenergic system plays a critical role in regulating lipolysis and thermogenesis. Recent studies have suggested that a missense Trp64Arg mutation in the beta3-adrenergic receptor gene is involved in visceral obesity and insulin resistance. We investigated the effect of this mutation on insulin resistance in patients with angiographically documented coronary heart disease ([CHD]n = 137) and normal subjects (n = 188). Plasma glucose and insulin responses to a 75-g oral glucose tolerance test and insulin resistance measured by the insulin suppression test, were determined in 58 (42%) patients with CHD and 121 (64%) controls. The genotype and allele frequency of the beta3-adrenergic receptor did not differ between patients with CHD and controls. The blood pressure, body mass index (BMI), waist to hip ratio, fasting plasma glucose, insulin, and lipid, and plasma glucose and insulin responses to the glucose load were relatively similar in subjects with and without the mutation in CHD and normal groups. The degree of insulin sensitivity, ie, the steady-state plasma glucose concentration, was not significantly different between subjects with and without the mutation in the CHD group (11.3 +/- 1.2, n = 11 v 11.9 +/- 0.6 mmol/L, n = 47, P = NS) and control group (8.4 +/- 0.7, n = 30 v 8.2 +/- 0.4 mmol/L, n = 91, P = NS). We conclude that Trp64Arg polymorphism of the beta3-adrenergic receptor gene does not likely play a major role in the development of CHD in the Chinese population. In addition, it appears to have no association with the insulin resistance syndrome in either CHD or non-CHD subjects.

Expression of melanocyte-associated markers gp-100 and Melan-A/MART-1 in angiomyolipomas. An immunohistochemical and rt-PCR analysis

Angiomyolipomas are tumours of uncertain histogenesis, most often occurring in association with the kidney. A characteristic finding is their reactivity with HMB-45, a monoclonal antibody to the melanocyte-associated antigen gp-100. We tested 18 angiomyolipomas for their reactivity with A103, a monoclonal antibody to Melan-A (MART-1), another melanocyte-associated marker, and compared it with HMB-45. All cases were positive with both antibodies, yet most cases showed a more homogeneous staining pattern with A103. Normal kidney was immunohistochemically negative for both antibodies. We also performed RT-PCR assays for gp-100 and Melan-A in 4 of the 18 angiomyolipoma samples and in three normal kidney samples. All 4 angiomyolipoma specimens revealed mRNA for both melanocyte differentiation markers. gp-100 mRNA was found in the samples of normal kidney, but Melan-A mRNA was not. Our study shows that angiomyolipomas express the melanocyte-associated antigens Melan-A and gp-100 at the protein and at the mRNA level, suggesting a true expression of these antigens rather than cross-reacting epitopes. Based on the mRNA expression pattern, immunohistochemical analysis is the preferred method for the detection of gp-100, while Melan-A can be used at the protein and mRNA levels. Our study demonstrates that A103 is a useful marker for the diagnosis of angiomyolipomas.

Isoforms of the human PDZ-73 protein exhibit differential tissue expression

Patients with renal and colon cancer frequently develop IgG autoantibodies toward the NY-CO-38/PDZ-73 antigen, a protein of 652 amino acids (73 kDa) which contains three copies of the PDZ protein-protein interaction domain. The gene encoding PDZ-73 mapped to chromosome 11p15.4-p15.1. Additional tissue-specific isoforms were identified: PDZ-45, which lacks the third PDZ domain and the putative PEST protein degradation motif, is expressed in kidney, colon, small intestine, brain and testis; PDZ-54 and PDZ-59, which also lack the third PDZ domains, have unique carboxyl terminal amino acids and are expressed in brain, kidney, bladder, colon cancer and renal cancer; and a putative PDZ-37 isoform, containing only the third PDZ domain, that is expressed in the central nervous system. Immunohistochemical staining with anti-PDZ 73 monoclonal antibodies showed strong cytoplasmic reactivity in epithelial cells of the small intestine, colon and kidney tubules, with a prominent apical staining pattern in cells of the small intestine. The reactivity pattern of the antibodies with various tissues correlated with the mRNA expression pattern of the PDZ-45 isoform. The existence of multiple PDZ-73 isoforms with variations in tissue distribution, PDZ domains, protein degradation sequences and carboxyl terminal structure indicate that these isoforms have distinct tissue-specific functions.