Abstract S2-01: The PRIME II trial: Wide local excision and adjuvant hormonal therapy ± postoperative whole breast irradiation in women ≥ 65 years with early breast cancer managed by breast conservation

Background. Local Recurrence rates after breast conserving surgery (BCS) are falling because of increasing use of effective systemic therapy. The question of whether whole breast radiotherapy (WBRT) can be omitted in carefully defined groups of older patients receiving appropriate systemic therapy has not been addressed. PRIME II is an International phase III RCT addressing this question.

Methods. Between April 2003 and December 2009, 1326 patients were randomised to receive (n = 658) or nor receive (n = 668) radiotherapy (RT). Eligiblity criteria were ≥65 years, T1-2 (up to 3cm), N0, M0, hormone receptor positive, clear excision margins (≥ 1mm), axillary node negative women in receipt of adjuvant hormone therapy. Patients could have Grade 3 tumours or lympho-vascular invasion but not both. An accrual of 1300 was planned to detect a difference based on estimates of local recurrence of 2% in RT group and 5% in no RT arm at 5 years, with 80% power and 5% significance. The primary endpoint was ipsilateral breast tumour recurrence (IBTR). Secondary endpoints were regional recurrence, contralateral breast cancer, distant metastases and overall survival (OS). Median follow up is 5.0 years.

Results

IBTR at 5 years was 4.1% (95% CI 2.4, 5.7%) without RT, 1.3% (95% CI 0.2, 2.3%) with RT. The hazard ratio for IBTR in those IBTR receiving radiotherapy was 4.34 (1.79, 10.55) (p = 0.001).

Overall actuarial survival at 5 years was 93.8% (95% CI 91.6, 95.9%) without RT and 94.2% (95% CI 92.2, 96.3%) with RT, (p = 0.24). No significant differences in regional recurrence (1.4% no RT vs 0.5% RT), contralateral breast cancer (0.9% no RT vs 1.5% RT), nor distant metastases (1.0% vs 0.3%) were seen. Breast cancer-free survival was 94.6% (95% CI 92.7, 96.5%)for no RT and 97.3% (95% CI 95.9, 98.8%) for those receiving RT (p = 0.003): this difference was due to the greater IBTR in no RT group. The majority of deaths were not linked to breast cancer (35 no RT vs 29 RT from a total of 87 deaths), with no influence of omission of RT (p = 0.27).

Conclusions

The randomised International Trial has shown that

• Omission of RT in women ≥65 year of age with N0, ER positive breast cancer receiving endocrine therapy results in only a 4.1% 5 year IBTR

• Although RT reduces IBTR significantly, the absolute reduction in this study is very small.

• RT does not reduce the rate of regional recurrence, distant metastases or affect overall survival.

• Omission of postoperative WBRT in this population based on the 5 year rate of IBTR appears safe, especially in the presence of comorbidities.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S2-01.

Skin testing and food challenges for the evaluation of food allergy

Skin testing by prick technique has an excellent safety record in the evaluation of food hypersensitivity. Skin prick tests for the common food allergens are excellent tools for identifying those at very low risk of reaction on eating the food but are of variable value in identifying patients who will be positive on challenge. Intradermal skin tests to foods are less safe and appear to add no predictive information. Skin tests to less common food allergens, especially fruits, are less well characterized and may require use of the food item itself as the source of allergen rather than a commercial extract. For a few foods, the CAP system fluorescent enzyme immunoassay (Pharmacia, Peapack, NJ) recently has been shown to have good ability to identify patients at very high probability of reaction on oral challenge. Oral challenge remains the definitive method of demonstrating sensitivity or tolerance to a food. The double-blind, placebo-controlled food challenge is the gold standard of diagnosis, but in many situations, simpler open or single-blind challenge procedures may be substituted. With careful, incremental dosing and a low starting dose, oral challenges for food hypersensitivity have an excellent safety record. Skin prick tests are of little value in the evaluation of adverse food reactions not mediated by IgE. Oral challenge is relied upon in this situation for definitive diagnosis, but challenges may be cumbersome if the time course of the presumed reaction is not rapid.

Health and economic benefits of increased beta-blocker use following myocardial infarction

CONTEXT

beta-blockers are underused in patients who have myocardial infarction (MI), despite the proven efficacy of these agents. New evidence indicates that beta-blockers can have benefit in patients with conditions that have been considered relative contraindications. Understanding the consequences of underuse of beta-blockers is important because of the implications for current policy debates over quality-of-care measures and Medicare prescription drug coverage.

OBJECTIVE

To examine the potential health and economic impact of increased use of beta-blockers in patients who have had MI.

DESIGN AND SETTING

We used the Coronary Heart Disease (CHD) Policy Model, a computer-simulation Markov model of CHD in the US population, to estimate the epidemiological impact and cost-effectiveness of increased beta-blocker use from current to target levels among survivors of MI aged 35 to 84 years. Simulations included 1 cohort of MI survivors in 2000 followed up for 20 years and 20 successive annual cohorts of all first-MI survivors in 2000-2020. Mortality and morbidity from CHD were derived from published meta-analyses and recent studies. This analysis used a societal perspective.

MAIN OUTCOME MEASURES

Prevented MIs, CHD mortality, life-years gained, and cost per quality-adjusted life-year (QALY) gained in 2000-2020.

RESULTS

Initiating beta-blocker use for all MI survivors except those with absolute contraindications in 2000 and continuing treatment for 20 years would result in 4300 fewer CHD deaths, 3500 MIs prevented, and 45,000 life-years gained compared with current use. The incremental cost per QALY gained would be $4500. If this increase in beta-blocker use were implemented in all first-MI survivors annually over 20 years, beta-blockers would save $18 million and result in 72,000 fewer CHD deaths, 62,000 MIs prevented, and 447,000 life-years gained. Sensitivity analyses demonstrated that the cost-effectiveness of beta-blocker therapy would always be less than $11,000 per QALY gained, even under unfavorable assumptions, and may even be cost saving. Restricting beta-blockers only to ideal patients (those without absolute or relative contraindications) would reduce the epidemiological impact of beta-blocker therapy by about 60%.

CONCLUSIONS

Our simulation indicates that increased use of beta-blockers after MI would lead to impressive gains in health and would be potentially cost saving. JAMA. 2000;284:2748-2754.

Cost-effectiveness of cholesterol-lowering therapies according to selected patient characteristics

BACKGROUND

The National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel II) recommends treatment guidelines based on cholesterol level and number of risk factors.

OBJECTIVE

To evaluate how the cost-effectiveness ratios of cholesterol-lowering therapies vary according to different risk factors.

DESIGN

Cost-effectiveness analysis.

DATA SOURCES

Published data.

TARGET POPULATION

Women and men 35 to 84 years of age with low-density lipoprotein cholesterol levels of 4.1 mmol/L or greater (> or =160 mg/dL), divided into 240 risk subgroups according to age, sex, and the presence or absence of four coronary heart disease risk factors (smoking status, blood pressure, low-density lipoprotein cholesterol level, and high-density lipoprotein cholesterol level).

TIME HORIZON

30 years.

PERSPECTIVE

Societal.

INTERVENTIONS

Step I diet, statin therapy, and no preventive treatment for primary and secondary prevention.

OUTCOME MEASURES

Incremental cost-effectiveness ratios.

RESULTS OF BASE-CASE ANALYSIS

Incremental cost-effectiveness ratios for primary prevention with step I diet ranged from $1900 per quality-adjusted life-year (QALY) gained to $500000 per QALY depending on risk subgroup characteristics. Primary prevention with a statin compared with diet therapy was $54000 per QALY to $1400000 per QALY. Secondary prevention with a statin cost less than $50000 per QALY for all risk subgroups.

RESULTS OF SENSITIVITY ANALYSIS

The inclusion of niacin as a primary prevention option resulted in much less favorable incremental cost-effectiveness ratios for primary prevention with a statin (>$500000 per QALY).

CONCLUSIONS

Cost-effectiveness of treatment strategies varies significantly when adjusted for age, sex, and the presence or absence of additional risk factors. Primary prevention with a step I diet seems to be cost-effective for most risk subgroups but may not be cost-effective for otherwise healthy young women. Primary prevention with a statin may not be cost-effective for younger men and women with few risk factors, given the option of secondary prevention and of primary prevention in older age ranges. Secondary prevention with a statin seems to be cost-effective for all risk subgroups and is cost-saving in some high-risk subgroups.

Skin testing and food challenges in allergy and immunology practice

Skin tests by prick technique offer considerable guidance in the diagnosis of food allergy. Negative prick skin tests are powerful evidence against food allergy. Positive food skin tests are slightly to moderately predictive of reaction to a food on DBPCFC. Oral food challenge is necessary for confirmation of food allergy, except where the history is overwhelmingly convincing. Open, incremental food challenge as described is diagnostic if negative, but only 50% of all positive open challenges are confirmed on blinded challenge. DBPCFC can be designed for any food with simple blinding techniques. The technique of DBPCFC can be modified for investigation of atypical symptoms.

Cost-effectiveness of donepezil in the treatment of mild or moderate Alzheimer's disease

OBJECTIVE

To demonstrate the use of cost-effectiveness analysis to assess the economic impact of donepezil in the treatment of mild or moderate AD.

BACKGROUND

Cost-effectiveness analyses show the relationship between resources used (costs) and health benefits achieved (effects) for an intervention compared with an alternative strategy.

METHODS

We developed a model to estimate the incremental cost-effectiveness of donepezil compared with no treatment. We determined costs per quality-adjusted life-years gained, a measurement that enhances the comparability of diverse studies. The model projects the progression of AD patients into more severe disease stages and into nursing homes. Data from a randomized clinical trial of donepezil were used to assess the drug's impact on the 6-week probabilities of progression. Data on the costs and health-related quality of life associated with different disease stages and settings were taken from published estimates and our companion cross-sectional study, respectively.

RESULTS

Donepezil costs are partially offset by a reduction in the costs of care due to enhancement in cognitive functioning and the delay to more costly disease stages and settings. The magnitude of this cost offset and of the effect of donepezil on health-related quality of life depends on the model's assumptions about the duration of the drug effect, where controlled data are lacking. If the drug effect exceeds 2 years, the model predicts that for mild AD the drug would pay for itself in terms of cost offsets.

CONCLUSIONS

The results of the cost-effectiveness model presented here suggest that donepezil may be cost-effective but additional controlled data on long-term drug efficacy are needed.

Hematopoietic stem-cell transplantation for the treatment of severe combined immunodeficiency

BACKGROUND

Since 1968 it has been known that bone marrow transplantation can ameliorate severe combined immunodeficiency, but data on the long-term efficacy of this treatment are limited. We prospectively studied immunologic function in 89 consecutive infants with severe combined immunodeficiency who received hematopoietic stem-cell transplants at Duke University Medical Center between May 1982 and September 1998.

METHODS

Serum immunoglobulin levels and lymphocyte phenotypes and function were assessed and genetic analyses performed according to standard methods. Bone marrow was depleted of T cells by agglutination with soybean lectin and by sheep-erythrocyte rosetting before transplantation.

RESULTS

Seventy-seven of the infants received T-cell-depleted, HLA-haploidentical parental marrow, and 12 received HLA-identical marrow from a related donor; 3 of the recipients of haploidentical marrow also received placental-blood transplants from unrelated donors. Except for two patients who received placental blood, none of the recipients received chemotherapy before transplantation or prophylaxis against graft-versus-host disease. Of the 89 infants, 72 (81 percent) were still alive 3 months to 16.5 years after transplantation, including all of the 12 who received HLA-identical marrow, 60 of the 77 (78 percent) who were given haploidentical marrow, and 2 of the 3 (67 percent) who received both haploidentical marrow and placental blood. T-cell function became normal within two weeks after transplantation in the patients who received unfractionated HLA-identical marrow but usually not until three to four months after transplantation in those who received T-cell-depleted marrow. At the time of the most recent evaluation, all but 4 of the 72 survivors had normal T-cell function, and all the T cells in their blood were of donor origin. B-cell function remained abnormal in many of the recipients of haploidentical marrow. In 26 children (5 recipients of HLA-identical marrow and 21 recipients of haploidentical marrow) between 2 percent and 100 percent of B cells were of donor origin. Forty-five of the 72 children were receiving intravenous immune globulin.

CONCLUSIONS

Transplantation of marrow from a related donor is a life-saving and life-sustaining treatment for patients with any type of severe combined immunodeficiency, even when there is no HLA-identical donor.

Congenital immunodeficiency syndromes

Cogenital abnormalities of innate or acquired immunity, although not common, produce multiple problems for which the surgeon may be consulted. Even if the diagnosis has not been previously made, patients with abnormal situs, congenital heart disease, failure to heal surgical wounds, pneumatoceles, lymphoproliferative disorders, recurrent severe infections, or autoimmune destruction of formed elements of the blood may have one of the disorders discussed above.

Pneumatosis intestinale in children with primary combined immunodeficiency

We report six episodes of pneumatosis intestinale (PI) in children with primary combined immunodeficiency. PI was generally benign and responded to conservative therapy. Increased risk of infection or disruption of gastrointestinal mucosa are probable predisposing factors. A diagnosis of PI should be considered in children with primary combined immunodeficiency who experience otherwise unexplained gastrointestinal symptoms, particularly in the early post-transplant period.

Complete DiGeorge syndrome: persistence of profound immunodeficiency

OBJECTIVE

DiGeorge syndrome is characterized by developmental defects of the heart, parathyroid glands, and thymus. The objective of this study was to determine whether T-cell function spontaneously improves in patients with DiGeorge syndrome who have profoundly depressed T-cell proliferative responses to mitogens at presentation, regardless of the T-cell count.

STUDY DESIGN

We conducted a retrospective chart review of eight patients with DiGeorge syndrome who had no proliferative responses to mitogens on presentation.

RESULTS

Despite lack of responsiveness of the patients' peripheral blood lymphocytes to mitogens, T cells were occasionally detected, and the patients' cells often responded to IL-2 and in mixed lymphocyte reactions. Unresponsiveness to mitogens and clinical immunodeficiency persisted without immune-based therapy. One patient is alive and well after immunoreconstitution from thymic transplantation. The others either died early of complications of their disease such as gastroesophageal reflux with aspiration (2 patients) or infection (2 patients) or died after attempts at immunorestorative therapy with IL-2, thymus transplantation, or bone marrow transplantation (3 patients).

CONCLUSION

Eight patients with DiGeorge syndrome who were first seen with no mitogen responsiveness did not improve spontaneously. We recommend HLA-identical bone marrow transplantation or thymic transplantation for these patients as soon as the diagnosis is confirmed.

Human severe combined immunodeficiency: genetic, phenotypic, and functional diversity in one hundred eight infants

OBJECTIVE

To determine the relative frequencies of the different genetic forms of severe combined immunodeficiency (SCID) and whether there are distinctive characteristics of the particular genotypes.

STUDY DESIGN

The demographic, genetic, and immunologic features of 108 infants with SCID who were treated consecutively at Duke University Medical Center were analyzed.

RESULTS

Eighty-nine subjects were boys and 19 were girls; there were 84 white infants, 16 black infants, and 8 Hispanic infants. Forty-nine had X-linked SCID with mutations of common cytokine receptor gamma chain (gamma c), 16 had adenosine deaminase (ADA) deficiency, 8 had Janus kinase 3 (Jak3) deficiency, 21 had unknown autosomal recessive mutations, 1 had reticular dysgenesis, 1 had cartilage hair hypoplasia, and 12 (all boys) had SCID of undetermined type. Deficiency of ADA caused the most profound lymphopenia; gamma c or Jak3 deficiency resulted in the most B cells and fewest natural killer (NK) cells; NK cells and function were highest in autosomal recessive and unknown types of SCID.

CONCLUSIONS

Different SCID genotypes are associated with distinctive lymphocyte characteristics. The presence of NK function in ADA-deficient, autosomal recessive, and unknown type SCIDs, and low NK function in a majority of gamma c and Jak3 SCIDs indicates that some molecular lesions affect T, B, and NK cells (gamma c and Jak3), others primarily T cells (ADA deficiency), and others just T and B cells.

The recent decline in mortality from coronary heart disease, 1980-1990. The effect of secular trends in risk factors and treatment

OBJECTIVE

To examine whether secular trends in risk factor levels and improvements in treatment can account for the observed decline in coronary heart disease mortality in the United States from 1980 to 1990 and to analyze the proportional contribution of these changes.

DATA SOURCES

Literature review, US statistics, health surveys, and ongoing clinical trials.

STUDY SELECTION

Data representative of the US situation nationwide reported in adequate detail.

DATA EXTRACTION

A computer-simulation state-transition model of the US population between the ages of 35 and 84 years was developed to forecast coronary mortality. The input variables were estimated such that the combination of values led to an adequate agreement with reported coronary mortality figures. Subsequently, secular trends were modeled.

DATA SYNTHESIS

Actual coronary mortality in 1990 was 34% (127,000 deaths) lower than would be predicted if risk factor levels, case-fatality rates, and event rates in those with and without coronary disease remained the same as in 1980. When secular changes in these factors were included in the model, predicted coronary mortality in 1990 was within 3% (10,000 deaths) of the observed mortality and explained 92% of the decline; only 25% of the decline was explained by primary prevention, while 29% was explained by secondary reduction in risk factors in patients with coronary disease and 43% by other improvements in treatment in patients with coronary disease.

CONCLUSIONS

These results suggest that primary and secondary risk factor reductions explain about 50% of the striking decline in coronary mortality in the United States between 1980 and 1990 but that more than 70% of the overall decline in mortality has occurred among patients with coronary disease.

Cost-effectiveness of populationwide educational approaches to reduce serum cholesterol levels

BACKGROUND

The aim of the present study was to estimate the cost-effectiveness of populationwide approaches to reduce serum cholesterol levels in the US adult population.

METHODS AND RESULTS

This cost-effectiveness analysis was made from data from the literature and the Coronary Heart Disease Policy Model and was based on the US population age 35 to 84 years. Study interventions were populationwide programs to reduce serum cholesterol levels with costs and cholesterol-lowering effects similar to those reported from the Stanford Three-Community Study, the Stanford Five-City Project, and in North Karelia, Finland. The main outcome measures were cost-effectiveness ratios, defined as the change in projected cost divided by the change in projected life-years when the population receives the intervention compared with the population without the intervention. A populationwide program with the costs ($4.95 per person per year) and cholesterol-lowering effects (an average 2% reduction in serum cholesterol levels) of the Stanford Five-City Project would prolong life at an estimated cost of only $3200 per year of life saved. Under a wide variety of assumptions, a populationwide program would achieve health benefits at a cost equivalent to that of many currently accepted medical interventions. Such programs would also lengthen life and save resources under many scenarios, especially if the program affected persons with preexisting heart disease or altered other coronary risk factors.

CONCLUSIONS

Populationwide programs should be part of any national health strategy to reduce coronary heart disease.

Multicenter crossover comparison of the safety and efficacy of Intraglobin-F with Gamimune-N, Sandoglobulin, and Gammagard in patients with primary immunodeficiency diseases

The safety and clinical efficacy of a liquid, beta-propiolactone-stabilized intravenous gamma-globulin, Intraglobin-F, was evaluated in a multicenter, double-blind study comparing Intraglobin-F to Gamimune-N, Sandoglobulin, or Gammagard. beta-Propiolactone stabilizes the IgG molecule to decrease aggregate formation and is a potent virucidal agent that reduces the risk of viral transmission by intravenous gamma-globulin (IVIG) preparations. Twenty-seven patients with primary immunodeficiency diseases were enrolled at three centers. Each patient received 6 months of therapy with either Intraglobin-F or the IVIG preparation that they had received during the preceding 3 months, then crossed over to the other preparation. Twenty-three patients completed the study. One patient withdrew because of an adverse event, generalized urticaria. A second patient withdrew because of fatigue and perceived decreased efficacy. Adverse reactions were comparable and occurred in 8.7% of the infusions of Intraglobin-F and 6% of the infusions with Sandoglobulin. None were severe or life-threatening. There was no discernible difference in efficacy between any of the products. The number of days when patients noted symptoms in their diaries was similar for Intraglobin-F and the comparison preparations, 4158 vs 4143. Similarly, there were no differences in the number of physician visits (33 vs 22), days missed from work or school (405 vs 404), days with fever (41 vs 47), or days of prophylactic antibiotics (675 vs 642). There was an increase in the number of days when antibiotics were given therapeutically (578 vs 451); most of the difference was attributable to one patient. There also was a difference in the number of days of hospitalization (21 vs 0), but 19 of the days were accounted for by two patients. When the patients were asked to score their feeling of well-being on a scale of 1 to 5, with 1 being entirely well, the mean score for the patients on Intraglobin-F was 1.86 (range, 1.0 to 3.0), compared to 1.85 (range, 1.0 to 3.2) for patients while on the comparison preparations. Trough IgG levels were slightly lower during the period when patients were treated with Intraglobin-F compared to the other products. There were no abnormalities in blood chemistries or hematologic parameters. Thus, Intraglobin-F is comparable to three of the marketed IVIG preparations in efficacy and safety, as well as patient acceptability, and offers the additional benefit of an extra virucidal step to reduce further the risk of transmitting viral infections.

Prospective oral food challenge study of two soybean protein isolates in patients with possible milk or soy protein enterocolitis

The soybean protein isolate used in powdered soybean formula is hydrolyzed more extensively than the isolate which is used in liquid soybean formula in most commercial soybean formulas. Previous in vitro studies have shown differences in human antibody response to these soybean protein isolates. Therefore, a prospective clinical study was undertaken to determine if there were differences in adverse reaction rates to these soybean protein isolates. Forty-three patients with possible milk- and/or soy-protein enterocolitis were enrolled in this study. Patients had 3 separate oral food challenges; using milk formula, soybean powder formula and soybean liquid formula. Ten (23%) patients challenged with milk had positive challenges. Fourteen (33%) patients challenged with powdered soy formula had positive challenges while thirteen (30%) challenged with liquid soy formula had positive challenges. In the 10 patients with positive milk challenges, 6 (60%) had a positive soy challenge. In the group with positive soy challenges, 5 reacted to the powdered soy challenge done first, but not the second challenge with the liquid soy formula, and 4 patients reacted to the liquid soy formula challenge done first, but not the second challenge with the powdered soy formula. These results indicate that a significant number of patients with milk protein enterocolitis have soy protein enterocolitis. In addition, an order effect can be demonstrated in the soy challenges because of the tendency to react to the first soy challenge regardless of the type of isolate. These results suggest that a local immune effect caused by the protein may be present.

The production of interferon-gamma in response to a major peanut allergy, Ara h II correlates with serum levels of IgE anti-Ara h II

The current study was undertaken to examine the potential role of T cells in the pathogenesis of peanut allergy. Peripheral blood mononuclear cells (PBMCs) from patients with peanut allergy, patients with asthma, and nonatopic normal control subjects were assessed for proliferation after stimulation with a 17 kd major peanut allergen (Ara h II), ovalbumin, casein, soy, and Candida albicans. We found that Ara h II and C. albicans induced significantly higher levels of proliferation than ovalbumin, casein, and soy. Because interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) play critical roles in IgE regulation, we assessed the production of these cytokines after stimulation with C. albicans and Ara h II. C. albicans stimulated similar levels of IFN-gamma in all three study groups. In contrast, after stimulation with Ara h II, culture supernatants from PBMCs of subjects with peanut allergy contained significantly lower levels of IFN-gamma than did the PBMCs of the two control groups (p = 0.02). More important, there was a significant (p = 0.05) inverse correlation between the serum IgE anti-Ara h II levels and IFN-gamma production by PBMCs from the respective peanut-allergic patients. IL-4 protein was not detected in culture supernatants of PBMCs stimulated with Ara h II. However, amplification of cytokine gene transcripts by polymerase chain reaction did demonstrate IL-4 expression in Ara h II-stimulated PBMCs from both patients with peanut allergy and control subjects. These data suggest that the level of IFN-gamma production in response to Ara h II may be an important factor in determining the development of peanut-specific IgE responses.

Isolation of the 36-kD German (Blattella germanica) cockroach allergen using fast protein liquid chromatography

Cockroach allergens have been established as important sensitizing agents in the induction of asthma. In the present investigation, we identified a 36-kD allergen from German cockroach (Blattella germanica) using fast protein liquid chromatography that reacted in the Bla g II monoclonal assay developed by Pollart et al. Defatted whole body German cockroaches were extracted in phosphate-buffered saline and fractionated using gel filtration (Superdex 75) and anion exchange (MonoQ) chromatography. The 36-kD allergen was isolated from this enriched allergen preparation by excision from modified preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gels, electroelution, dialysis and lyophilization. SDS-PAGE/Western immunoblot analysis using a serum pool of cockroach-sensitive individuals revealed a single band. The lyophilized 36-kD allergen was then analyzed for amino acid composition and digested for peptide amino acid sequencing.

Haploidentical bone marrow stem cell transplantation in human severe combined immunodeficiency

From May 1992 to March 1993, 50 infants with severe combined immunodeficiency (SCID) were given bone marrow transplants at Duke University Medical Center. None received chemotherapy for conditioning or for graft-versus-host disease (GVHD) prophylaxis. Forty-one received haploidentical parental marrow depleted of T cells by soybean lectin and sheep red blood cell resetting, and nine received HLA-identical marrow. Forty (80%) survived from 1 week to almost 11 years posttransplantation, including nine of nine (100%) HLA-identical marrow recipients and 31 of 41 haploidentical recipients. T-cell function was present within 2 weeks after transplantation of unfractionated HLA-identical marrow, but not until 3 to 4 months after T-cell-depleted haploidentical marrow stem cells. All 37 patients who are more than 4 months posttransplantation have good T-cell function, and all but one have 100% donor T cells. B-cell function developed slowly or not at all in some recipients of haploidentical marrow. Fourteen (four HLA-identical and 10 haploidentical recipients) have some donor B cells; 19 patients are receiving intravenous immune globulin (IVIG) therapy.

Cost-effectiveness considerations in the treatment of heterozygous familial hypercholesterolemia with medications

When used for the primary prevention of coronary heart disease in persons with heterozygous familial hypercholesterolemia (hFH), a hydroxymethylglutaryl coenzyme A (HMG CoA) reductase inhibitor is projected to be effective and to have very favorable cost-effectiveness ratios at low-to-medium doses. For example, 20 mg of lovastatin per day is estimated to save lives and save money in all men ages 35-44 years with hFH and in women ages 35-44 years with hFH and any other risk factor. The estimated incremental cost effectiveness of 40 mg compared with 20 mg of lovastatin for individuals with hFH ages 35-44 years was less than $45,000 per year of life saved in men with > or = 1 other risk factors and women with > or = 2 other risk factors. The estimated incremental cost-effectiveness ratio of 80 mg compared with 40 mg/day was substantially higher ($100,000 or more per year of life saved) even in the highest risk persons. The estimated cost-effectiveness ratios for primary prevention in hFH were reasonably similar to the favorable ratios for secondary prevention in the general population but substantially better than the estimated ratios for primary prevention in other adults with high cholesterol levels. Any national recommendations regarding the use of medications for individuals with hFH must include cost considerations. Our analyses support the use of low-to-moderate doses of high-cost medications for primary prevention in these patients.

Identification of cockroach aeroallergens from living cultures of German or American cockroaches

The Air Sentinel and polytetrafluoroethylene (PTFE) membranes were used to capture airborne particles over living colonies of German or American cockroaches. Silver-stained SDS-PAGE gels revealed protein bands at 80, 55, 36, and several bands below the 33-kD marker. SDS-PAGE/immunoblots of PTFE eluates from German cockroach colonies incubated with serum from cockroach-sensitive individuals revealed IgE-binding bands with apparent molecular weights of 36 and 80 kD. Only the 36-kD allergen and allergens below the 33-kD marker were evident in the American PTFE eluate. ELISA analysis with a monoclonal antibody assay identified the presence of both Bla g I and Bla g II in the German PTFE eluate. No Bla g I or Bla g II could be identified in the American PTFE eluate. These studies demonstrate that in addition to Bla g I and Bla g II, several other aerosolized allergens become airborne over cockroach colonies and may be important in the environment where cockroaches are abundant.

Allergenicity of peanut and soybean extracts altered by chemical or thermal denaturation in patients with atopic dermatitis and positive food challenges

Peanuts and soybeans are two of the six most common foods to cause food hypersensitivity reactions in children. We used the serum of 10 patients with atopic dermatitis and positive double-blind, placebo-controlled, food challenges to peanut and two patients with atopic dermatitis and positive double-blind, placebo-controlled, food challenges to soybean to investigate the change in IgE-specific and IgG-specific binding to these proteins altered by either chemical or thermal denaturation. We used IgE- and IgG-specific ELISA-inhibition analyses to compare these effects on the crude peanut and crude soy extracts, as well as on the major allergenic fractions of both proteins. Heating the soy proteins at various temperatures and time intervals did not significantly change the IgE- or IgG-specific binding of the soy positive pooled serum. When the peanut proteins were subjected to similar heating experiments, the IgE- and IgG-specific binding did not change. When these same proteins were treated with enzymes in the immobilized digestive enzyme assay system used to mimic human digestion, the binding of IgE to the crude peanut and crude soy extracts was reduced; 100-fold for peanut and 10-fold for soybean. Therefore it appears that thermal denaturation of peanut and soybean protein extracts does not enhance or reduce IgE- and IgG-specific binding activity. Chemical denaturation appears to minimally reduce the binding of these proteins.

Identification and characterization of a second major peanut allergen, Ara h II, with use of the sera of patients with atopic dermatitis and positive peanut challenge

Peanuts are frequently a cause of food hypersensitivity reactions in children. Serum from nine patients with atopic dermatitis and a positive double-blind, placebo-controlled, food challenge to peanut were used in the process of identification and purification of the peanut allergens. Identification of a second major peanut allergen was accomplished with use of various biochemical and molecular techniques. Anion exchange chromatography of the crude peanut extract produced several fractions that bound IgE from the serum of the patient pool with positive challenges. By measuring antipeanut specific IgE and by IgE-specific immunoblotting we have identified an allergic component that has two closely migrating bands with a mean molecular weight of 17 kd. Two-dimensional gel electrophoresis of this fraction revealed it to have a mean isoelectric point of 5.2. According to allergen nomenclature of the IUIS Subcommittee for Allergen Nomenclature this allergen is designated, Ara h II (Arachis hypogaea).

Egg hypersensitivity and measles-mumps-rubella vaccine administration

Because reports have described egg-sensitive individuals in whom anaphylaxis developed after measles vaccination, current recommendations include delaying administration of egg-derived vaccines until skin testing can be performed. Specifically, the 1988 Red Book recommends skin testing via scratch, prick, or puncture with 1:10 dilution of the vaccine and, if the result is negative, intradermal testing is suggested. The purpose of this study was to evaluate the likelihood of reaction to measles-mumps-rubella (MMR) vaccine in patients with documented egg sensitivity and to delineate the efficacy of skin-prick testing (SPT) to MMR as a predictor of hypersensitivity to the vaccine. Egg sensitivity was documented by initial SPT to egg and then, if possible, double-blind placebo-controlled food challenge (DBPCFC). Patients with a positive DBPCFC to egg or a history of anaphylactic egg sensitivity had a SPT with the MMR vaccine and then were given the MMR vaccine. Additionally, children with atopic dermatitis who had been previously proven egg sensitive via DBPCFCs were evaluated retrospectively for sensitivity to the MMR vaccine. Sixteen children with a history of egg sensitivity underwent SPT to egg, with a positive result 3 mm greater than the negative control found in 12 patients. Eight of these children had a positive DBPCFC to egg. The SPT to MMR vaccine was negative in all 16 children; vaccine administration followed with no resultant systemic problems. Three children had a local reaction at the site of injection. Twelve additional children with atopic dermatitis and egg sensitivity were reviewed. Each child had a positive SPT and DBPCFC to egg.(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of a major peanut allergen, Ara h I, in patients with atopic dermatitis and positive peanut challenges

Peanuts are among the most common causes of immediate hypersensitivity reactions to foods. Serum from nine patients with atopic dermatitis and a positive double-blind, placebo-controlled, food challenge to peanut were used to begin the process of identification and purification of the major peanut allergens. Identification of a major peanut allergen was accomplished by use of anion-exchange column chromatography, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, ELISA, thin-layer isoelectric focusing, and IgE-specific immunoblotting. Anion-exchange chromatography revealed several fractions that bound IgE from the serum of the challenge-positive patient pool. By measuring antipeanut-specific IgE in the ELISA and in IgE-specific immunoblotting, we identified an allergenic component with two Coomassie brilliant blue staining bands by sodium dodecyl sulfate-polyacrylamide gel electrophoresis with a mean molecular weight of 63.5 kd. Examination of this fraction by the IgE antipeanut ELISA with individual serum and by the ELISA-inhibition assay with pooled serum, we identified this fraction as a major allergen. Thin-layer isoelectric focusing and immunoblotting of this 63.5 kd fraction revealed it to have an isoelectric point of 4.55. Based on allergen nomenclature of the IUIS Subcommittee for Allergen Nomenclature, this allergen is designated, Ara h I (Arachis hypogaea).

Expected gains in life expectancy from various coronary heart disease risk factor modifications

BACKGROUND

Despite much evidence that modifying risk factors for coronary heart disease can decrease morbidity and mortality, little is known about the impact of risk-factor modification on life expectancy.

METHODS AND RESULTS

We used the Coronary Heart Disease Policy Model, a state-transition computer simulation of the US population, to forecast potential gains in life expectancy from risk-factor modification for the cohort of Americans turning age 35 in 1990. Among 35-year-old men, we projected that the population-wide increase in life expectancy would be about 1.1 years from strict blood pressure control, 0.8 years from smoking cessation, 0.7 years from reduction of serum cholesterol to 200 mg/dl, and about 0.6 years from weight loss to ideal body weight. For women, reducing cholesterol to 200 mg/dl would have the greatest estimated impact-a gain of 0.8 years-whereas smoking cessation, blood pressure control, or weight loss would yield population-wide gains of 0.7, 0.4, and 0.4 years, respectively. Gains for 35-year-old individuals having a given risk factor are greater. We estimate that, on average, male smokers would gain 2.3 years from quitting smoking; males with hypertension would gain 1.1-5.3 years from reducing their diastolic blood pressure to 88 mm Hg; men with serum cholesterol levels exceeding 200 mg/dl would gain 0.5-4.2 years from lowering their serum cholesterol level to 200 mg/dl; and overweight men would gain an average of 0.7-1.7 years from achieving ideal body weight. Corresponding projected gains for at-risk women are 2.8 years from quitting smoking, 0.9-5.7 years from lowering blood pressure, 0.4-6.3 years from decreasing serum cholesterol, and 0.5-1.1 years from losing weight. Eliminating coronary heart disease mortality is estimated to extend the average life expectancy of a 35-year-old man by 3.1 years and a 35-year-old woman by 3.3 years.

CONCLUSIONS

Population-wide gains in life expectancy from single risk-factor modifications are modest, but gains to individuals at risk can be more substantial.

Cost-effectiveness of HMG-CoA reductase inhibition for primary and secondary prevention of coronary heart disease

To determine the cost-effectiveness of HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase inhibitors (such as lovastatin) for the primary and secondary prevention of coronary heart disease, we used the Coronary Heart Disease Policy Model, a computer-stimulated model that estimates the risk factor-specific annual incidence of coronary heart disease and the risk of recurrent coronary events in persons with prevalent coronary heart disease. When used for secondary prevention, 20 mg/d of lovastatin was estimated to save lives and save costs in younger men with cholesterol levels above 250 mg/dL (6.47 mmol/L) and to have a favorable cost-effectiveness ratio regardless of the cholesterol level except in young women with cholesterol levels below 250 mg/dL (6.47 mmol/L). Doses of 40 mg/d of lovastatin had favorable incremental cost-effectiveness ratios in men with cholesterol levels above 250 mg/dL (6.47 mmol/L). By comparison, primary prevention had favorable cost-effectiveness ratios only in selected subgroups based on cholesterol levels and other established risk factors. We conclude that current national recommendations regarding medication for secondary prevention are not as aggressive as our projections would suggest, while recommendations regarding the use of medications for primary prevention should consider the cost of medication as well as the risk factor profile of the individual patient.

Long-term impact of smoking cessation on the incidence of coronary heart disease

Using a simulation model of the US male population, we estimated the long-term impact that future smoking cessation programs would have on the distribution and occurrence of coronary heart disease in males ages 35-84. For interventions that reduce the number of smokers by 25 percent in 1990, the number of men free of coronary heart disease is projected to increase by 416,787 (0.7 percent) in 2015, and the age-standardized absolute incidence to decline by 2.3 percent. Incidence rates and absolute incidences are projected to fall in men under age 65, but absolute incidence would rise in men over age 65, in large part because of the increased number of men who were at risk for coronary heart disease because of a reduction in non-coronary smoking-related mortality. These trends were more marked for greater smoking reductions and were generally unaffected in a variety of analyses using alternative assumptions, which considered smoking as a risk factor in the elderly, a lag-time before benefits from smoking cessation were realized and secular declines in smoking prevalence. Subject to the assumptions of our model, we conclude that smoking reductions will markedly reduce coronary heart disease, especially in younger age groups, and that this benefit will be slightly offset by a small increase in absolute incidence in elderly men.

Antibody response to milk proteins in patients with milk-protein intolerance documented by challenge

To evaluate the role of specific antibody response to milk proteins in patients with milk-protein intolerance, allergen-specific IGE, IgG, and IgG4 to these proteins were measured by ELISA. Bovine casein, gamma globulin (GG), beta-lactoglobulin, and lactalbumin were the milk proteins used. Antibody production to these proteins were analyzed in 18 patients who underwent milk-protein challenges (eight positive and 10 negative) and in five normal children used in the analysis. ELISA results for specific IgE, IgG, and IgG4 to these specific proteins demonstrated no statistically different response to the four milk proteins among the three patient groups by multivariate analysis. When the specific antibody results from the positive challenge group, the negative challenge group, and the normal group were combined, the IgE and IgG4 to GG and the IgG to casein were significantly higher (p less than 0.01) than the corresponding specific antibody to the other proteins tested. The IgG or IgG4 to GG would differentiate the positive from the negative challenge group (p less than 0.05) but were not significantly different from the normal control group. Contrary to previously published studies, these results indicate IgG specific for the milk proteins are not increased in patients with milk-protein intolerance. The data also support the concept that IgE and IgG4 are not elevated in these patients. Therefore, there appears to be no pathogenic role for these specific immunoglobulins in milk-protein intolerance.

Relative impact of targeted versus populationwide cholesterol interventions on the incidence of coronary heart disease. Projections of the Coronary Heart Disease Policy Model

We used the Coronary Heart Disease Policy Model, a state-transition computer simulation, to assess the absolute and relative effects of two different national cholesterol interventions: a targeted program to identify and treat all individuals with elevated serum cholesterol levels (greater than or equal to 250 mg/dl) versus a populationwide program to reduce everyone's serum cholesterol level. Based on the assumptions inherent in our model, which uses the Framingham Heart Study coefficients, we estimate the targeted program would reduce projected coronary heart disease absolute incidence by 8-10% in men ages 35-54 years and by 1-4% in men ages 55-74 years. Our model suggests that similar reductions in coronary heart disease incidence could be achieved by a 10 mg/dl populationwide reduction in serum cholesterol levels. In women, the targeted program would yield greater relative and absolute benefits and would be equivalent to a approximately 23 mg/dl populationwide reduction in serum cholesterol. We conclude that it would be inadvisable to rely solely on targeted cholesterol reduction programs to reduce national coronary heart disease.

Peanut protein as a major cause of adverse food reactions in patients with atopic dermatitis

Peanuts, along with milk and eggs, have been documented to account for approximately 80% of adverse reactions to foods in patients with atopic dermatitis. Over the past 3 years, we have evaluated 71 patients with atopic dermatitis, ranging from mild to severe in nature. These patients were initially evaluated by allergy prick skin testing and when appropriate had double-blind placebo-controlled food challenges done. Thirty-nine (55%) patients had a positive prick skin test to one of the foods tested. There were 80 food challenges performed with peanut, accounting for 12 (32%) of the 38 positive challenges in 23 (31%) patients. As in earlier studies, patients developed skin (97%), respiratory (55%), and gastrointestinal (32%) symptoms during the challenge. Of the five patients with histories of prior anaphylactic reactions four (80%) were to peanut. These studies indicate that children with all degrees of atopic dermatitis may benefit from evaluation for food hypersensitivity. They also show that peanut is a major food protein responsible for these reactions.

Enzyme-linked immunosorbent assay and immunoblotting determination of antibody response to major component proteins of soybeans in patients with soy protein intolerance

To evaluate the role of food-specific antibody response to soy protein and its fractions in patients with soy protein intolerance, allergen-specific IgG and IgE to these proteins were measured by enzyme-linked immunosorbent assays (ELISAS) and immunoblotting. A crude soy extract and the 7S, 11S, and whey fractions were isolated from commercial defatted soy flakes. Of 23 patients who underwent standardized soy challenges, seven were positive. The ELISA results showed no statistically different responses between the challenge-positive and challenge-negative groups in IgG or IgE specific to either the crude soy extract or the 7S, 11S, and whey fractions (p greater than .3 for all variables). In comparing the soy-positive patients, the level of IgE specific for 7S and 11S was significantly different compared with whey; the level of IgE specific for crude soy extract and 7S was significantly different compared with whey. The immunoblots reveal that IgG and IgE are present in varying amounts to multiple fractions of the soy protein. The study does not provide evidence for a pathogenic role of serum food-specific antibodies in soy protein intolerance.

Atopic dermatitis: clinical relevance of food hypersensitivity reactions

Forty-six patients with atopic dermatitis ranging from mild to severe were evaluated for food hypersensitivity with double-blind placebo-controlled food challenges. Twenty-eight (61%) patients had a positive prick skin reaction to one of the foods tested. Sixty-five food challenges were performed; 27 (42%) were interpreted as positive in 15 (33%) patients. Egg, milk, and peanut accounted for 78% of the positive reactions. As in previous studies, patients developed skin (96%), respiratory (52%), or gastrointestinal (30%) symptoms during the challenge. These studies indicate that children who have atopic dermatitis unresponsive to routine therapy or who continue to need daily treatment after several months would benefit from evaluation for food hypersensitivity.

Complement: function and clinical relevance

There is a remarkable array of proteins participating in the complement cascade, regulating the activation of the system, or recognizing a fragment of a component as a biologic signal. The classical pathway of complement activation depends on antigen-antibody interaction and is important as an effector arm of acquired humoral immunity to microorganisms. The alternative pathway functions as a form of innate humoral immunity by attacking membranes not having the characteristics of self-membrane. In addition, the alternative path provides amplification after triggering by either path. Absence or dysfunction of many of the components is associated with autoimmune or immunodeficiency disease. Absence of the inhibitor C1INH is associated with the unique syndrome of hereditary angioedema.

Intravenous immunoglobulin: new clinical applications

At the present time there are three commercially available intravenous immunoglobulin (IVIG) preparations. There is no distinct therapeutic advantage for any one product over any other. Intravenous immunoglobulin is currently approved for the treatment of antibody deficiency syndromes and for acute and chronic idiopathic thrombocytopenic purpura. In addition, controlled clinical trials have demonstrated efficacy for the treatment of Kawasaki disease and for the prevention of the following infections: sepsis in preterm neonates, sepsis in infants with AIDS, and cytomegalovirus infection in the immune-compromised host. Open (uncontrolled) studies have suggested benefit in the treatment of neonatal sepsis, chronic Epstein-Barr virus infection, and a number of autoimmune diseases. Additional carefully designed studies must be completed before IVIG therapy can be recommended for these latter categories. In published reports, dosage of IVIG and intervals between infusions have varied considerably. For all current indications, the physician must therefore individualize treatment and thoroughly review any recent literature that may clarify guidelines to IVIG therapy. Significant adverse reactions are rare but high cost remains the main obstacle to more routine implementation.

Forecasting coronary heart disease incidence, mortality, and cost: the Coronary Heart Disease Policy Model

A computer simulation model was developed to project the future mortality, morbidity, and cost of coronary heart disease (CHD) in the United States population. The model contains a demographic-epidemiologic (DE) submodel, which stimulates the distribution of coronary risk factors and the conditional incidence of CHD in a demographically evolving population; a "bridge" submodel, which determines the outcome of the initial CHD event; and a disease history (DH) submodel, which simulates subsequent events in persons with a previous CHD event. The user of the model may simulate the effects of interventions, either preventive (i.e., risk factor modification) or therapeutic, upon mortality, morbidity, and cost for up to a 30-year period. If there were no future changes in risk factors or the efficacy of therapies after 1980, baseline projections indicate that the aging of the population, and especially the maturation of the post-World War II baby-boom generation, would increase CHD prevalence and annual incidence, mortality, and costs by about 40-50 per cent by the year 2010. Unprecedented reductions in risk factors would be required to offset these demographic effects on the absolute incidence of CHD. The specific forecasts could be inaccurate, however, as a consequence of erroneous assumptions or misestimated baseline data, and the model awaits validation based on actual future data.

Study of the feline and canine populations in the greater Las Vegas area

Analysis of household dogs and cats, based on age-distribution data and on age-specific birth and survival rates, as well as on pet source, indicated that the dog and cat populations are stable and not increasing in size (lambda congruent to 1). Roaming dogs and cats euthanatized at the pound represented about 5.7% and 8.1% of the estimated dog and cat populations, respectively. The death at the pound seems to be effective in checking pet population growth. Among pets acquired, 84% were less than 1 year of age for dogs as compared with 88% for cats. Breeders and pet shops supplied about 7% of cats and 17% of dogs. About 10% of cats and 10% of dogs were acquired at the pound, while 6.4% of dogs and 14% of cats were acquired as stray. About 45% of dogs and 41% of cats were acquired from pet owners. Some dogs (12.46%) and cats (12%) were imported from outside the Las Vegas area. Of dogs and cats below 2 months of age, 33% and 19.5%, respectively, came from breeders or pet shops or were imported from outside the area. Seventeen percent of unspayed female dogs and 16% of unspayed female cats reproduced. The percentages of spayed females were 77 for dogs and 86 for cats. Forty-five percent of the dogs and 48% of the cats were males. Among dogs at the shelter, 2% were neutered and 26% spayed. At the pound, 24% of dogs were small breeds, 24% medium size breeds, and 52% large breeds.(ABSTRACT TRUNCATED AT 250 WORDS)

Cataracts in Chesapeake Bay Retrievers

Cataracts developed in 13 of 27 related Chesapeake Bay Retrievers. The posterior pole, "Y" sutures, and equatorial cortices of the lens were predominantly affected. In one affected dog, the cataracts had progressed to hypermaturity, permitting restoration of vision. The trait was believed to be dominant, with incomplete penetrance.

Uveoscleral flow of aqueous humor in the normal dog

Fluorescein-labeled dextran and sodium fluorescein perfused in the posterior chamber of the normal dog eye egressed through the trabecular meshwork and intrascleral plexus, as well as posteriorly through the ciliary body into the suprachoroidal space and the sclera. Intraocular pressures of 20, 25, 30, and 60 mm of Hg did not produce detectable changes in the fluorescein-labeled dextran movement. Topical 1% atropine and 10% phenylephrine did not affect posterior passage of sodium fluorescein; 2% pilocarpine impeded posterior passage, causing an accumulation of sodium fluorescein and associated fluorescence in the anterior ciliary body.

Evaluation of a soluble sustained-release ophthalmic delivery unit in the dog

A 5-mg hydroxypropyl cellulose soluble ocular insert was evaluated by placement in the upper and the lower conjunctival and bulbar nictitating membrane fornices in normal dogs. The insert was easily placed in the conjunctival fornices, but was difficult to place in the bulbar nictitating membrane fornix. The conjunctival inserts did not produce irritation of the cornea and the conjunctiva. Placement of the inserts beneath the nictitating membrane produced local irritation and chemosis. The sites of highest to lowest retention for the insert were upper conjunctival fornix, bulbar nictitating membrane fornix, and lastly, lower conjunctival fornix. Dissolution was nearly complete in 8 hours.

Ocular hypotensive effects of carbonic anhydrase inhibitors in normotensive and glaucomatous Beagles

Four carbonic anhydrase inhibitors (acetazolamide, dichlorphenamide, ethoxzolamide, and methazolamide) cause ocular hypotony in normotensive and glaucomatous Beagles. Four dosages of acetazolamide and methazolamide and three dosages of dichlorphenamide and ethoxzolamide were evaluated. The extent of ocular hypotony after these carbonic anhydrase inhibitors was usually greater in glaucomatous Beagles than it was in normotensive Beagles.

Clinical manifestations of inherited glaucoma in the beagle

Inherited glaucoma was exhibited in 55 beagles. The glaucomatous process was divided into early (6 to 12 months of age), moderate (13 to 30 months of age), and advanced (31 months of age). In early glaucoma the tridocorneal angles, as judged by gonioscopy, were open and without anomalies, intraocular pressure was elevated, and the tonographic facility of aqueous outflow was decreased. With moderate glaucoma, the tridocorneal angles were typically open; intraocular pressure was elevated, facility of aqueous outflow was decreased; and variable optic disc cupping and focal disinsertion of the zonules from the lens were seen. Advanced glaucoma exhibited narrow to closed tridocorneal angles, decreased facility of aqueous outflow, elevated intraocular pressure, lens dislocation, optic disc atrophy, and finally phthisis bulbi. The beagle in the early and moderate stages of glaucoma, before angle closure and lens dislocation, is an animal model for studies in open-angle glaucoma.

The effect of topical pilocarpine on intraocular pressure and pupil size in the normotensive and glaucomatous beagle

Topical 1, 2, and 4 percent pilocarpine were evaluated in the normotensive and glaucomatous beagles, comparing intraocular pressure (IOP), pupillary size, and time. In normotensive beagles pilocarpine produced maximal decreases of 25 percent (5.5 mm. Hg) at 1 percent concentration; 34 percent (7.26 mm. Hg) at 2 percent concentration; and 25 percent (6.9 mm. Hg) at 4 percent concentration. The maximum reductions in IOP after pilocarpine instillation in the glaucomatous beagle were 30 percent (9.1 mm. Hg) at 1 percent concentration; 44 percent (14.92 mm. Hg) at 2 percent concentration; and 31 percent (10.89 mm. Hg) at 4 percent concentration. The glaucomatous beagles responded with a greater reduction of IOP than did the normotensive beagles.