Predictors of colon cancer screening among low-income urban minority residents: The Cancer Risk Assessment in Baltimore (CRAB) Study

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Background: Colorectal cancer mortality can be reduced through early detection, using recommended screening tests (fecal occult blood test (FOBT), sigmoidoscopy, or colonoscopy). However, screening is underutilized, especially among low-income and racial/ethnic minority groups. Few studies have examined determinants of screening in these groups. Methods: We analyzed data on predictors of colon cancer screening from a cross-sectional study of Baltimore City Residents (N = 534). Participants responded to a questionnaire administered by an interviewer, on screening practices, behavioral, social and demographic factors, including income level. Eligible respondents for this analysis were age = 50, aware of colorectal screening tests, but not diagnosed with colon polyps or cancer. Multivariate techniques were used to examine predictors of having undergone any recommended colon cancer screening test. Results: The eligible population for this analysis (N=202) was 49.0 % male and 51.0 % female. The median income fell within the $12,000-$24,999 bracket. The proportion of participants that had received colon cancer screening was 34.5 % among those in the highest income bracket (i.e. =$25,000) compared to 30.0 % in the lowest income bracket (i.e. =$11,999). This difference was statistically significant after adjusting for other sociodemographic factors (odds ratio (OR)=3.12, p=0.023). Multivariate analysis indicated that screening was associated with having one (OR: 3.56, p=0.016) or more than one (OR: 7.31, p=0.006) primary health care provider. Having health care coverage, a doctor who recommended exercise, and having at least some college education, were also associated with screening. Conclusions: Negative predictors of colorectal cancer screening include: extremely low income levels (= $11,999), lack of health care coverage, primary care providers, and college education level. Provider recommendations for healthy behaviors (e.g. exercise) are associated with patient adherence to recommended cancer screenings. The design of interventions to promote use of screening tests by low-income populations should be informed by the substantial heterogeneity in patient and provider characteristics within these populations.

No significant financial relationships to disclose.

Recruitment strategies in the Asthma Clinical Research Network

In any clinical trial, recruitment of trial participants usually requires an intense effort to reach the target sample size. The Asthma Clinical Research Network (ACRN) was keenly aware of this issue at its inception and therefore initiated and emphasized recruitment strategies for each of its clinical trials. This article describes the recruitment strategies for the ACRN's first four major clinical trials. Particular attention is given to the strategies for the recruitment of women and minorities. Finally, the specific strategies of each of the six ACRN clinical centers are presented.

Patterns and predictors of asthma-related emergency department use in Harlem

STUDY OBJECTIVES

To assess the roles of poor access to care, psychological risk factors, and asthma severity in frequent emergency department (ED) use.

DESIGN

A cross-sectional survey.

SETTING

Harlem Hospital Center ED and outpatient chest clinic.

PARTICIPANTS

Three hundred seventy-five adult residents of Harlem, a predominantly African-American community in New York City.

MEASUREMENTS

Asthma severity was assessed by self-reported symptoms using National Asthma Education and Prevention Program guidelines, health-care utilization, and psychometric scales.

RESULTS

Respondents with more severe asthma were more likely to have a primary asthma care provider, and to have had more scheduled office visits for asthma in the year prior to the interview (mean number of visits for patients with severe asthma, 3.6 visits; moderate asthma, 2.4 visits; and mild asthma, 1.7 visits). Despite having a regular source of care, 69% of respondents identified the ED as their preferred source of care; 82% visited the ED more than once in the year prior to interview (median, four visits). Persons with moderate or severe asthma were 3.8 times more likely to be frequent ED users compared to those with mild asthma (odds ratio [OR], 3.8; 95% confidence interval [CI], 2.2 to 6.6). This was the strongest predictor of frequent ED use. Other predictors of ED use were number of comorbid disorders (OR, 1.5; 95% CI, 1.1 to 2.1) and self-reported global health in the year prior to the ED visit (OR, 1.8; 95% CI, 1.2 to 2.7). Psychological characteristics were not predictive of frequent ED use when controlling for disease severity.

CONCLUSIONS

Frequent ED users present with serious medical conditions. They do not substitute physician care with ED care; they augment it to address serious health needs.

Characteristics and correlates of asthma knowledge among emergency department users in Harlem

We constructed a questionnaire to assess asthma knowledge, assessed its psychometric properties, and examined its association with demographic characteristics, psychosocial factors, and disease severity and management in 375 adults following an asthma-related emergency department visit. Overall knowledge was poor but varied widely among respondents. Better knowledge was related to younger age, higher education, and less severe disease. Chance-orientated health locus of control and low self-esteem were associated with lower asthma knowledge. Better knowledge was associated with better disease management. We conclude that asthma education can lead to improved disease outcomes, and psychosocial factors need to be considered when designing interventions for asthma education.

Prenatal exposure, maternal sensitization, and sensitization in utero to indoor allergens in an inner-city cohort

Primary sensitization to antigens may occur prenatally. We hypothesized that high prenatal exposure to indoor antigens increases the risk for sensitization in newborns in New York City populations with increased risk for asthma. We also investigated whether maternal sensitization is required for in utero sensitization to occur. One hundred sixty-seven pregnant African American or Dominican women residing in northern Manhattan were recruited and antigen was measured from home dust. After delivery, newborn cord and maternal blood were assayed for IgE and mononuclear cell proliferation and cytokine production in response to antigen. Cockroach, mouse, but not dust mite antigens, were commonly elevated in the kitchens and pregnant mothers' beds. Increased mononuclear cell proliferation occurred in 54% of newborns in response to cockroach, 25% in response to dust mite Dermatophagoides pteronyssinus, 40% in response to dust mite D. farinae, and 34% in response to mouse protein extracts. Antigen-induced mononuclear cell proliferation occurred in cord blood even in the absence of antigen-induced mononuclear cell proliferation in the mother. Proliferation in response to antigens did not correlate with IgE levels, but proliferation in response to dust mite extracts correlated with interluekin-5 (IL-5) production in cord blood. These results suggest that (1) high prenatal exposures to cockroach and mouse antigens are prevalent; (2) in utero sensitization to multiple indoor antigens is common, occurs to a different degree than maternal sensitization, and may involve IL-5 upregulation.

Catalytic asymmetric ring-opening metathesis/cross metathesis (AROM/CM) reactions. Mechanism and application to enantioselective synthesis of functionalized cyclopentanes

Studies regarding the first examples of catalytic asymmetric ring-opening metathesis (AROM) reactions are detailed. This enantioselective cleavage of norbornyl alkenes is followed by an intermolecular cross metathesis with a terminal olefin partner; judicious selection of olefin is required so that oligomerization and dimerization side products are avoided. Results outlined herein suggest that the presence of suitably positioned heteroatom substituents may be critical to reaction efficiency. Mo-catalyzed tandem AROM/CM affords functionalized cyclopentyl dienes in >98% ee and >98% trans olefin selectivity; both secondary and tertiary ether products can be obtained. The examples provided include the catalytic synthesis of an optically pure cyclopentyl epoxide and dimethyl acetal. Mechanistic studies suggest that it is the more substituted benzylidene or silylated alkylidenes that are involved in the catalytic process (vs the corresponding Mo-methylidenes). Although electron rich benzylidenes react more efficiently, the derived electron poor Mo complexes promote AROM/CM transformations as well; alkylidenes that bear a boron substituent are unreactive.

Il-13 and IFN-gamma: interactions in lung inflammation

Chronic inflammatory diseases of the lungs, such as asthma, are frequently associated with mixed (Th2 and Th1) T cell responses. We examined the impact of critical Th1 and Th2 cytokines, IFN-gamma and IL-13, on the responses in the lungs. In a mouse model of airway inflammation induced by mixed T cell responses, the number of Th1 (IFN-gamma-positive) cells was found to be negatively correlated with airway hyperreactivity. In these mice, blockade of IL-13 partially inhibited airway hyperreactivity and goblet cell hyperplasia but not inflammation. In contrast, in mice that responded with a polarized Th2 response to the same Ag, blockade of IL-13 inhibited airway hyperreactivity, goblet cell hyperplasia, and airway inflammation. These results indicated that the presence of IFN-gamma would modulate the effects of IL-13 in the lungs. To test this hypothesis, wild-type mice were given recombinant cytokines intranasally. IFN-gamma inhibited IL-13-induced goblet cell hyperplasia and airway eosinophilia. At the same time, IFN-gamma and IL-13 potentiated each other's effects. In the airways of mice given IL-13 and IFN-gamma, levels of IL-6 were increased as well as numbers of NK cells and of CD11c-positive cells expressing MHC class II and high levels of CD86. In conclusion, IFN-gamma has double-sided effects (inhibiting some, potentiating others) on IL-13-induced changes in the lungs. This may be the reason for the ambiguous role of Th1 responses on Th2 response-induced lung injury.

Safety and reproducibility of sputum induction in asthmatic subjects in a multicenter study

The safety of sputum induction and the reproducibility of measurements in induced sputum in multicenter studies is unknown. We examined the safety of sputum induction in a two-visit, six-center study in 79 subjects with moderate to severe asthma (mean +/- SD FEV(1) 71 +/- 12% predicted, 67% taking inhaled corticosteroids). In addition, we compared the reproducibility of markers of inflammation in induced sputum with the reproducibility of the FEV(1) and the methacholine PC(20). The FEV(1) decreased > or = 20% from the postbronchodilator baseline in 14% of all subjects and in 25% of subjects whose initial prebronchodilator baseline was 40 to 60% of predicted. All subjects responded promptly to additional albuterol treatment, and no subject developed refractory bronchoconstriction requiring treatment other than reversal of bronchospasm in the study laboratory. The reproducibility of measurements of the eosinophil percentage, eosinophil cationic protein, tryptase, and methacholine PC(20) were similar (concordance correlation coefficients of 0.74, 0.81, 0.79, and 0.74, respectively), without any significant among-center effect. We conclude that sputum induction can be performed safely in subjects with moderate to severe asthma in multicenter clinical trials when carried out under carefully monitored conditions. Importantly, we demonstrate that measurement of markers of inflammation in induced sputum is as reproducible as methacholine PC(20) and should prove useful in the assessment of airway inflammation in multicenter clinical trials.

Standards for assessment of lung function and respiratory health in minority populations: some challenges linger into the new millennium

Results of pulmonary function tests (as an indicator of respiratory health) are from 11 to 13 percent lower in African Americans and other racial ethnic populations than in Caucasians when controlled for gender, age, and height. Environmental factors influencing these indices are circadian variation, altitude, air pollutants, technology, state of nutrition, smoking history, and other indicators of lifestyle. A combination of subtle, genetically determined anthropometric variants may also be operative, the extent of which is controversial. Population-based, population-specific standards are required to avoid erroneous diagnosis of cardiorespiratory disease, erroneous assessment of operative risk, unfair hiring practices when lung function tests are used for preemployment evaluation in dusty occupations, and unfair labeling when workers apply for disability compensation. Tailoring of statistical prediction standards from simple linear to more complex polynomial regression models will increase the accuracy of population prediction standards for pulmonary function variables into the 21st century.

Inhaled corticosteroid reduction and elimination in patients with persistent asthma receiving salmeterol: a randomized controlled trial

CONTEXT

Inhaled long-acting beta(2)-agonists improve asthma control when added to inhaled corticosteroid (ICS) therapy.

OBJECTIVE

To determine whether ICS therapy can be reduced or eliminated in patients with persistent asthma after adding a long-acting beta(2)-agonist to their treatment regimen.

DESIGN AND SETTING

A 24-week randomized, controlled, blinded, double-dummy, parallel-group trial conducted at 6 National Institutes of Health-sponsored, university-based ambulatory care centers from February 1997 through January 1999.

PARTICIPANTS

One hundred seventy-five patients aged 12 through 65 years with persistent asthma that was suboptimally controlled during a 6-week run-in period of treatment with inhaled triamcinolone acetonide (400 microg twice per day).

INTERVENTION

Patients continued triamcinolone therapy and were randomly assigned to receive add-on therapy with either placebo (placebo-minus group, n = 21) or salmeterol xinafoate, 42 microg twice per day (n = 154) for 2 weeks. The entire placebo-minus group was assigned and half of the salmeterol group (salmeterol-minus group) was randomly assigned to reduce by 50% (for 8 weeks) then eliminate (for 8 weeks) triamcinolone treatment. The other half of the salmeterol group (salmeterol-plus group) was randomly assigned to continue both salmeterol and triamcinolone for the remaining 16 weeks (active control group).

MAIN OUTCOME MEASURE

Time to asthma treatment failure in patients receiving salmeterol.

RESULTS

Treatment failure occurred in 8.3% (95% confidence interval [CI], 2%-15%) of the salmeterol-minus group 8 weeks after triamcinolone treatment was reduced compared with 2.8% (95% CI, 0%-7%) of the salmeterol-plus group during the same period. Treatment failure occurred in 46.3% (95% CI, 34%-59%) of the salmeterol-minus group 8 weeks after triamcinolone therapy was eliminated compared with 13.7% (95% CI, 5%-22%) of the salmeterol-plus group. The relative risk (95% CI) of treatment failure at the end of the triamcinolone elimination phase in the salmeterol-minus group was 4.3 (2.0-9.2) compared with the salmeterol-plus group (P<.001).

CONCLUSIONS

Our results indicate that in patients with persistent asthma suboptimally controlled by triamcinolone therapy alone but whose asthma symptoms improve after addition of salmeterol, a substantial reduction (50%) in triamcinolone dose can occur without a significant loss of asthma control. However, total elimination of triamcinolone therapy results in a significant deterioration in asthma control and, therefore, cannot be recommended.

Long-acting beta2-agonist monotherapy vs continued therapy with inhaled corticosteroids in patients with persistent asthma: a randomized controlled trial

CONTEXT

Long-acting beta(2)-agonists are prescribed for patients with persistent asthma and are sometimes used without inhaled corticosteroids (ICSs). No evidence exists, however, to support their use as monotherapy in adults with persistent asthma.

OBJECTIVE

To examine the effectiveness of salmeterol xinafoate, a long-acting beta(2)-agonist, as replacement therapy in patients whose asthma is well controlled by low-dose triamcinolone acetonide, an ICS.

DESIGN AND SETTING

A 28-week, randomized, blinded, placebo-controlled, parallel group trial conducted at 6 National Institutes of Health-sponsored, university-based ambulatory care centers from February 1997 to January 1999.

PARTICIPANTS

One hundred sixty-four patients aged 12 through 65 years with persistent asthma that was well controlled during a 6-week run-in period of treatment with inhaled triamcinolone (400 microg twice per day).

INTERVENTIONS

Patients were randomly assigned to continue triamcinolone therapy (400 microg twice per day; n = 54) or switch to salmeterol (42 microg twice per day; n = 54) or to placebo (n = 56) for 16 weeks, after which all patients received placebo for an additional 6-week run-out period.

MAIN OUTCOME MEASURES

Change in morning and evening peak expiratory flow (PEF), forced expiratory volume in 1 second (FEV(1)), self-assessed asthma symptom scores, rescue albuterol use, asthma-specific quality-of-life scores, treatment failure, asthma exacerbation, bronchial reactivity, and markers of airway inflammation, compared among the 3 treatment groups.

RESULTS

During the 16-week randomized treatment period, no significant differences between the salmeterol and triamcinolone groups were observed for conventional outcomes of clinical studies of asthma therapy-morning PEF, evening PEF, asthma symptom scores, rescue albuterol sulfate use, or quality of life. Both active treatments were superior to placebo. However, the salmeterol group had more treatment failures than the triamcinolone group (13/54 [24%] vs 3/54 [6%]; P =.004), as well as more asthma exacerbations (11/54 [20%] vs 4/54 [7%]; P =.04), greater increases in median (interquartile range) sputum eosinophils (2.4% [0.0% to 10.6%] vs -0.1% [-0.7% to 0.3%]; P<.001), eosinophil cationic protein (71 [-2 to 430] U/L vs -4 [-31 to 56] U/L; P =.005), and tryptase (3.1 [2.1 to 7.6] ng/mL vs 0.0 [0.0 to 0.7] ng/mL; P<.001). The duration of benefit when patients were switched from active treatment to placebo after 22 weeks of randomized treatment was not significantly longer in the triamcinolone group than in the salmeterol group.

CONCLUSIONS

Patients with persistent asthma well controlled by low doses of triamcinolone cannot be switched to salmeterol monotherapy without risk of clinically significant loss of asthma control.

Effect of polymorphism of the beta(2)-adrenergic receptor on response to regular use of albuterol in asthma

BACKGROUND

Regular use of inhaled beta-adrenergic agonists may have adverse effects in some asthma patients. Polymorphisms of the beta(2)-adrenergic receptor (beta(2)-AR) can affect its regulation; however, results of smaller studies of the effects of such polymorphisms on response to beta-agonist therapy have been inconsistent.

METHODS

We examined the possible effects of polymorphisms at codons 16 (beta(2)-AR-16) and 27 (beta(2)-AR-27) on response to albuterol by genotyping 190 asthmatics who had participated in a trial of regular versus as-needed albuterol use.

RESULTS

During the 16-week treatment period, patients homozygous for arginine (Arg/Arg) at beta(2)-AR-16 who used albuterol regularly had a small decline in morning peak expiratory flow (AM PEF). This effect was magnified during a 4-week run-out period, when all patients returned to as-needed albuterol only. By the end of the study, Arg/Arg subjects who had used albuterol regularly had an AM PEF 30.5 +/- 12.1 liters/min lower (p = 0.012) than Arg/Arg patients who had used albuterol as needed only. Subjects homozygous for glycine at beta(2)-AR-16 showed no such decline. Evening PEF also declined in the Arg/Arg regular but not in as-need albuterol users. No significant differences between regular and as-needed treatment were associated with polymorphisms at beta(2)-AR-27.

CONCLUSIONS

Polymorphisms of the beta(2)-AR may influence airway responses to regular inhaled beta-agonist treatment.

Dopamine and intraocular pressure in critically ill patients

BACKGROUND

A recently released dopamine-1 receptor agonist, fenoldopam, increases intraocular pressure (IOP) in both healthy volunteers and patients with chronic ocular hypertension. Dopamine, a potent agonist at both dopamine-1 and -2 receptors, is frequently infused in critically ill patients for its inotropic, renal vasodilatory, and natriuretic effects. The authors hypothesized that low doses of dopamine would significantly increase IOP.

METHODS

Patients in the intensive care unit who were currently receiving dopamine infusions of less than 5 microg x kg(-1) x min(-1) were studied After local ocular anesthesia was obtained, baseline IOP was measured in each eye with a hand-held tonometer. IOP was then determined after dopamine was discontinued.

RESULTS

Twenty-three patients received a mean dopamine infusion of 2.6 +/- 0.2 microg x kg(-1) x min(-1). Twelve of the 23 patients were receiving mechanical ventilation during the study. Mean IOPs in nonventilated patients (n = 11) off dopamine were 13.1 +/- 0.9 mmHg (left eye) and 12.6 +/- 0.9 mmHg (right eye). Mean IOPs for the same patients receiving dopamine were significantly higher at 16.1 +/- 0.9 mmHg (left eye) and 15.9 +/- 1.1 mmHg (right eye). Mean IOPs in intubated patients (n = 12) off dopamine were 12.3 +/- 0.7 mmHg (left eye) and 12.5 +/- 1.2 mmHg (right eye). Mean IOPs for the same patients while receiving dopamine were significantly higher in intubated patients at 17.8 +/- 1.3 mmHg (left eye) and 17.3 +/- 1.3 mmHg (right eye). The average mean elevation in IOP in patients while receiving dopamine was significantly higher in intubated patients as compared with nonintubated patients (5.2 +/- 0.9 mmHg vs. 3.1 +/- 0.6 mmHg).

CONCLUSIONS

Commonly used doses of dopamine are associated with increased IOP in critically ill patients. Although normal patients should be able to tolerate this elevation safely for several weeks, there may be a potential risk in patients with preexisting glaucomatous nerve damage or ocular hypertension, especially if they are sedated and mechanically ventilated.

5-Fluorouracil for the treatment of intraepithelial neoplasia of the conjunctiva and cornea

OBJECTIVE

To evaluate the efficacy of pulse dosing of topical 5-fluorouracil (5-FU) in the treatment of conjunctival and corneal intraepithelial neoplasia.

DESIGN

Prospective, noncomparative case series.

PARTICIPANTS

Seven patients with histologic evidence of intraepithelial neoplasia were identified by conjunctival biopsy or tumor excision.

METHODS

Seven patients with a minimum of 7 months of follow-up were treated with pulsed dosing of 1% 5-FU. Topical 1% 5-FU was administered four times daily for 2 to 4 days for each cycle. The number of initial treatment cycles was two to six, with the time between cycles being 30 to 45 days.

MAIN OUTCOME MEASURES

The presence or absence of clinically evident intraepithelial neoplasia was evaluated after each treatment interval. Patients were also monitored for adverse reactions to the use of topical 5-FU.

RESULTS

Four patients remain disease free with a mean follow-up of 18.5 months (range, 7-36 months) with no additional treatment after the initial treatment cycles (mean, 3.75 cycles; range, 2-5 cycles). Three patients had recurrence of disease after the initial treatment cycles. Two patients were treated with additional cycles for recurrent disease (six cycles in one patient and five cycles in the other patient) and are free of disease at 20 and 21 months after treatment, respectively. One patient had persistent disease despite treatment with topical 5-FU and was treated with topical mitomycin C with resolution of the disease without recurrence for 16.5 months. No adverse reactions to pulse dose treatment with topical 5-FU were noted.

CONCLUSIONS

Pulsed dosing with 1% topical 5-FU for the treatment of conjunctival and corneal intraepithelial neoplasia, alone or as an adjunct to excision of bulky disease, is a well-tolerated and effective method of treatment.

Glutathione S-transferase M1 polymorphism and lung cancer risk in African-Americans

Glutathione S:-transferase M1 (GSTM1) can detoxify many carcinogens, including polycyclic aromatic hydrocarbons such as those from cigarette smoke. Though a number of studies have been published about the association between GSTM1 polymorphism and lung cancer, this association has received limited attention in the African-American population. We conducted a case-control study to investigate the role of GSTM1 polymorphism in the development of lung cancer in African-Americans. Specimens of DNA from 117 lung cancer cases and 120 controls were assayed for detection of GSTM1 genotype by polymerase chain reaction (PCR). The odds ratios (ORs) and 95% confidence intervals (CIs) for lung cancer associated with homozygous deletion of the GSTM1 gene and other risk factors were estimated by logistic regression. Thirty-seven of the 117 cases (31. 6%) and 24 of the 120 controls (20.0%) had the GSTM1 null genotype; the OR was 2.10 (95% CI 1.07-4.11) after adjustment for age, gender and smoking. The association was higher for squamous cell carcinoma (OR 2.98, 95% CI 1.09-8.19) than for adenocarcinoma (OR 1.95, 95% CI 0.81-4.66). We observed a stronger association between GSTM1 null genotype and lung cancer among heavy smokers with > or =30 pack-years (OR 4.35, 95% CI 1.16-16.23). This association was also found in squamous cell carcinoma (OR 6.26, 95% CI 1.31-29.91). In the analysis combining GSTM1 polymorphism and smoking, smokers with the null genotype had high risk (OR 8.19, 95% CI 2.35-28.62) compared with non-smokers with the wild-type genotype, and the risk increased with smoking cigarette pack-years (P: = 0.0001 for trend). Our results suggest that GSTM1 polymorphism plays a role in the development of lung cancer and modifies the risk for smoking-related lung cancer in African-Americans.

The effect of polymorphisms of the beta(2)-adrenergic receptor on the response to regular use of albuterol in asthma

Inhaled beta-adrenergic agonists are the most commonly used medications for the treatment of asthma although there is evidence that regular use may produce adverse effects in some patients. Polymorphisms of the beta(2)-adrenergic receptor (beta(2)-AR) can affect regulation of the receptor. Smaller studies examining the effects of such polymorphisms on the response to beta-agonist therapy have produced inconsistent results. We examined whether polymorphisms at codon 16 (beta(2)-AR-16) and codon 27 (beta(2)-AR-27) of the beta(2)-AR might affect the response to regular versus as-needed use of albuterol by genotyping the 190 asthmatics who had participated in a trial examining the effects of regular versus as needed albuterol use. During the 16-wk treatment period there was a small decline in morning peak expiratory flow in patients homozygous for arginine at B(2)-AR-16 (Arg/Arg) who used albuterol regularly. This effect was magnified during a 4-wk run out period, during which all patients returned to using as-needed albuterol, so that by the end of the study Arg Arg patients who had regularly used albuterol had a morning peak expiratory flow 30. 5 +/- 12.1 L/min lower (p = 0.012) than Arg/Arg patients who had used albuterol on an as needed basis. There was no decline in peak flow with regular use of albuterol in patients who were homozygous for glycine at beta(2)-AR-16. Evening peak expiratory flow also declined in the Arg/Arg patients who used albuterol regularly but not in those who used albuterol on an as-needed basis. No significant differences in outcomes between regular and as-needed treatment were associated with polymorphisms at position 27 of the beta(2)-AR. No other differences in asthma outcomes that we investigated occurred in relation to these beta(2)-AR polymorphisms. Polymorphisms of the beta(2)-AR may influence airway responses to regular inhaled beta-agonist treatment.

Combined intraepithelial squamous neoplasia and atypical fibroxanthoma of the cornea and limbus

PURPOSE

To investigate a case of an unusual neoplasm of the cornea and limbus.

METHODS

A 59-year-old man presented with a highly vascularized, nodular mass involving the left cornea and limbus. An excisional biopsy and, subsequently, a superficial lamellar keratectomy and multiple conjunctival biopsies were performed. At the 6-month follow-up examination, repeat conjunctival biopsies were performed.

RESULTS

Histopathologic examination of the corneal specimen showed a high-grade intraepithelial squamous neoplasia (in situ carcinoma) overlying an atypical fibroxanthoma.

CONCLUSION

We report the clinical and histologic appearance of a corneal/limbal neoplasm consisting of an intraepithelial squamous neoplasia and an atypical fibroxanthoma.

Wound healing following anterior keratectomy and lamellar keratoplasty in the pig

PURPOSE

To examine corneal wound healing in an animal model of two types of mechanical lamellar keratectomy.

METHODS

One eye from each of 28 pigs was studied. Using a motorized keratome, corneas were subjected to an anterior lamellar keratectomy with removal of anterior stroma and epithelium, or to automated lamellar keratoplasty (ALK) with reapposition of a corneal flap. The exposed stromal surfaces were labeled intraoperatively with a fluorescent dye (DTAF) to assess deposition of stromal components during subsequent wound healing. Examination before surgery and enucleation included measurement of corneal curvature and intraocular pressure, and assessment of corneal haze. Eyes were prepared for histological examination, fluorescence microscopy, and for fibronectin immunohistochemistry.

RESULTS

Both keratectomy procedures produced flattening of corneas by up to 3.80 diopters, 28 days after surgery. Corneal haze was more pronounced in eyes from which epithelium was removed (anterior lamellar keratectomy group). The increased haze in this group was associated histologically with appearance of many reactive keratocytes and inflammatory cells, deposition of new stromal material, and more widespread appearance of fibronectin immunoreactivity. In the lamellar keratoplasty group, only the edges of the corneal wound showed significant reactivity, and included keratocyte activation and epithelial ingrowth.

CONCLUSIONS

The pig provides a useful model for studies of refractive surgical techniques using procedures and instruments designed for use in humans. Mechanized keratectomy procedures that minimize disruption of the epithelium and Bowman's layer produce a less reactive corneal wound than procedures in which an expanse of epithelium and anterior stroma are removed.

Association between a sequence variant in the IL-4 gene promoter and FEV(1) in asthma

Recent family-based studies have revealed evidence for linkage of human chromosome 5q31 to the diagnosis of asthma, elevated serum IgE levels, and bronchial hyperresponsiveness. Among the candidate genes in this region is the gene encoding for human interleukin-4 (IL-4). We reasoned that this gene could also serve as a candidate gene with respect to asthma severity as indicated by the FEV(1) measured when bronchodilator treatment was withheld. To test this hypothesis, we examined a large population of patients with asthma (ascertained without respect to genetic characteristics), for associations between a genetic variant in the IL-4 promoter region (C-589T) and asthma severity, as indicated by FEV(1). We used amplification by the polymerase chain reaction followed by BsmF1 restriction digestion to assign genotypes at the IL-4 promoter C-589T locus. We compared genotypes at this locus in 772 Caucasian and African American patients with asthma of varying severity, and we used multiple regression analysis to relate genotypic findings to FEV(1). Among white individuals, the homozygous presence of the C-589T IL-4 promoter genotype (TT) was associated with a FEV(1) below 50% of predicted (p = 0.013; OR, 1.44; 95% CI: 1.09 to 1.90). Subjects with the TT genotype had mean FEV(1) (% predicted) values 4.5% lower than those of subjects with the wild-type (CC) genotype at this locus. FEV(1) values of white patients with a CC or CT genotype were broadly distributed, whereas the TT genotype was associated with a narrow distribution of low FEV(1) values. The frequency of the T allele was significantly greater (p = 1 x 10(-)(23)) among African American asthmatics (0.544) than among white asthmatics (0.183). These data provide the first evidence associating FEV(1) in patients with asthma and genetic determinants at any locus. Our data are consistent with the idea that the FEV(1) in asthma is the result of multiple factors; one of these factors is the genotype at the IL-4 C-589T locus. This locus is associated with a small but significant decrement in pulmonary function among white asthmatic subjects.

Nontuberculous mycobacterial keratitis in south Florida

OBJECTIVE

This study aimed to review the clinical features, therapeutic response, and histopathology of cases of nontuberculous mycobacterial keratitis at the Bascom Palmer Eye Institute.

DESIGN AND PARTICIPANTS

Retrospective review of medical records, clinical photographs, histopathology, and microbiology of 24 cases of nontuberculous acid-fast keratitis over the past 15 years.

RESULTS

Causal organisms included Mycobacterium chelonae (16), M. fortuitum (3), M. avium-intracellulare (2), M. nonchromogenicum (1), M. triviale (1), and M. asiaticum (1). Clinically, the keratitis had a superficial location except in those patients with a history of surgery. Amikacin was the most commonly used antibiotic (63%). Three patients were treated with Clarithromycin. In one patient, it was stopped because of toxicity; the other two had resolution of their infiltrates. Fifty-five percent did not respond to topical antimicrobial therapy. The organisms as a group were sensitive to amikacin and Clarithromycin and resistant to the fluoroquinolones. Sixty-four percent of the group that failed to respond to medical treatment were treated with steroids after the diagnosis was known, in comparison to 44% of the group treated successfully with medications. The histopathology of the patients treated with steroids showed minimal inflammation despite a large number of organisms, in contrast to the dense infiltrates seen in the specimens from patients not treated with topical steroids.

CONCLUSION

Nontuberculous mycobacterial keratitis is a chronic insidious infection that is often unresponsive to medical therapy. The authors recommend that steroids be withheld. Based on the authors' experience of three patients, topical Clarithromycin may hold promise as a therapeutic agent. Lamellar keratectomy or penetrating keratoplasty should be considered in those patients who do not respond to medical therapy or those who have recurrent exacerbations on attempted weaning of topical antibiotic therapy.

Retrospective analysis of a novel method of transscleral suture fixation for posterior-chamber intraocular lens implantation in the absence of capsular support

PURPOSE

To determine the safety and efficacy of an alternative method for transscleral fixation of a secondary posterior-chamber intraocular lens (pcIOL) during penetrating keratoplasty.

METHODS

Eighty-nine eyes that underwent secondary pcIOL implantation by using a modified transscleral suture-fixation technique during penetrating keratoplasty were retrospectively evaluated. The surgical technique used suture fixation to the surface of the sclera 5 mm posterior to the limbus, with the knot buried beneath Tenon's capsule and conjunctiva. Patient records were reviewed for postoperative complications, including suture erosion, pcIOL subluxation, vitreous hemorrhage, and retinal detachment. Mean follow-up was 24.4 months, with a range of 4-68 months.

RESULTS

All eyes had successful fixation of their pcIOL immediately after surgery. Three (3.3%) eyes had graft failure. Six (6.7%) of 89 eyes showed evidence of suture erosion or partial exposure. Postoperative suture breakage occurred in two (2.2%) eyes. Posterior-segment complications included retinal detachment in one (1.1%) eye, vitreous hemorrhage in one (1.1%) eye, and limited choroidal hemorrhage in two (2.2%) eyes. Median visual acuity at 1-year follow-up was 20/70 (range, 20/25 to light perception).

CONCLUSION

This transscleral fixation technique provides a straightforward alternative to previously described techniques. Suture erosion, IOL dislocation, and posterior-segment complications occurred at relatively low rates compared with other pcIOL implantation techniques.

Bilateral monocular diplopia associated with lid position during near work

PURPOSE

To describe a common pattern of topographic changes and clinical signs of six patients presenting with a complaint of monocular diplopia after reading and to investigate the cause of this topographic disturbance.

METHODS

PATIENT POPULATION

Subject group of six patients with monocular diplopia complaints after reading and 20 patients without such complaints. Examinations performed before and after a reading period of 30 min: videokeratoscopic examination, red reflex examination, position of the lids in primary gaze and in reading position.

DATA ANALYSIS

inspection of keratoscopic rings, qualitative analysis of topography maps, comparison of SAI and SRI of control and subject groups before and after reading, comparison of lid position of control and subject group.

RESULTS

Half of the subject group and none of the control group developed subtle ring distortions of keratoscopic rings. SAI and SRI values increased significantly in the subject group compared with the control group (p = 0.02 and p < 0.001, respectively) corresponding to the development of a focal distortion in the entrance pupil of the videokeratoscopic image. Each subject developed a horizontal band on red reflex located at the superior, middle, or inferior aspect of the pupil after near work. Two controls developed faint bands in the red reflex outside the entrance pupil. The interpalpebral fissure in down gaze was narrower in the subject group compared with the control group (p = 0.001).

CONCLUSIONS

Some individuals may develop monocular diplopia after reading. We hypothesize that during near work these corneal topographic alterations occur primarily related to the position of the lids and tear film interaction with the corneal surface.

Central visual field changes associated with acquired pits of the optic nerve

BACKGROUND

With the increased use of a hand-held indirect lens and slit-lamp biomicroscopy for stereoscopic viewing of the optic nerve, the authors believe that an acquired pit of the optic nerve is more common than was recognized previously. This increased recognition has led to the awareness that the central visual field was affected frequently in the presence of such an acquired pit.

METHODS

The authors retrieved the charts of a series of 97 patients who had an acquired pit of the optic nerve during an 18-month period and retrospectively reviewed the automated visual fields associated with these pits using the Humphrey Visual Field Analyzer Programs 30-2 and 10-2 and looked for involvement of the central visual field.

RESULTS

In 81.7% of the acquired pits of the optic nerves, one of the central-most test points (3 degrees from fixation) in the appropriate hemifield on the 30-2 format was depressed severely by Statpac II (P < 0.5). The authors therefore restudied as many patients as possible using the 10-2 format to determine the extent of central visual field involvement in the presence of an acquired optic nerve pit. Among these patients, the 10-2 format demonstrated that the approach of the defect to fixation varied, but was frequently inside 3 degrees, reaching between 1 degrees and 3 degrees from fixation in 96.7% of the eyes with depression of at least one central point on the 30-2 format. It was more likely that an acquired pit located at the inferior pole of the optic nerve would produce a visual field defect within 3 degrees of fixation than such a pit at the superior pole (P = 0.03).

CONCLUSION

The authors showed that the presence of an acquired pit in an optic nerve damaged by glaucoma frequently is associated with a threat to fixation.

Topical 5-fluorouracil in treating epithelial neoplasia of the conjunctiva and cornea

PURPOSES

To evaluate the efficacy of topical 5-fluorouracil (5-FU) in treating conjunctival and corneal epithelial neoplasia.

METHODS

Three patients underwent surgical excision of bulky disease followed by topical 1% 5-FU in artificial tear base for 2 to 3 weeks or until epithelial separation occurred. An additional three patients underwent treatment with topical 1% 5-FU alone.

RESULTS

Minimum follow-up was 6 months. In one patient with conjunctival in situ carcinoma and no detectable normal conjunctiva, who had normal findings on conjunctival histologic examination after application of topical 5-FU, a focus of invasive disease requiring orbital exenteration. One patient had a favorable response to 5-FU therapy but required a repeat excision for control of bulky disease. Four patients have remained disease-free for 10, 13, 18, and 30 months after topical 5-FU therapy.

CONCLUSION

With its potential selective toxicity on dysplastic epithelium, topical 5-FU shows promise as an adjunctive treatment for managing conjunctival and corneal epithelial neoplasia.

Orbital cellulitis, subperiosteal abscess, sinusitis, and septicemia caused b Arcanobacterium haemolyticum

PURPOSE/METHODS

A 16-year-old boy had orbital cellulitis, subperiosteal abscess, sinusitis, and septicemia. Arcanobacterium haemolyticum was identified as the causative organism.

RESULTS/CONCLUSIONS

This organism is a cause of orbital cellulitis and may require aggresive therapy in order to achieve a therapeutic response.

Solid-phase hybridization capture of low-abundance target DNA sequences: application to the polymerase chain reaction detection of Mycobacterium paratuberculosis and Mycobacterium avium subsp. silvaticum

Polymerase chain reaction (PCR) has been widely applied to the detection of microorganisms. Overall sensitivity of PCR tests may be substantially reduced due to a large excess of nontarget DNA and inhibitory substances in the sample. We used a 5'-biotinylated 513-bp probe from the 3' region of the IS 900 element specific for Mycobacterium paratuberculosis (Mptb) to capture target Mptb DNA from crude sample DNA extracts. Captured target DNA was separated using streptavidin-coated magnetic particles (Dynal). Since the IS 900 element shares homology over this region with IS 902 in Mycobacterium avium subsp. silvaticum (Mavs), target DNA from this other pathogen was also retained. Highly specific PCR for the detection of either organism directed to the 5' regions of IS 900 or IS 902 was then performed directly on the solid phase. Hybridization capture of target DNA using sequence adjacent to the desired specific PCR site applied to Mptb increased overall sensitivity of detection in tissue and fecal extracts 10- to 100-fold. False positives due to contamination artifact were substantially excluded since the capture probe did not retain amplicons from the detection PCR. Development of the method to involve covalent 5' immobilization of capture probes on heat-resistant polymers should, in the future, provide a simple system with broad potential applications.

Tuberculosis: pathogenesis and laboratory diagnosis

Emerging molecular biologic technologies hold the promise of more rapid diagnosis of tuberculosis and more definitive epidemiologic linkages of cases of TB. In addition to reviewing the pathogenesis of tuberculosis, this chapter covers a variety of methods for the rapid detection of the disease, including the acid-fast smear, conventional culture, the BACTEC system, immunodiagnostic methods, and DNA-based techniques.

Air pollution health risks: do class and race matter?

Air pollution is not spread evenly across demographic groups. Exposures and associated health risks appear to fall disproportionately on populations that are poor and nonwhite. Although scientific evidence documenting disparities in air pollution exposures, doses, and health effects is scant, the available data strongly support the contention that disadvantaged groups, many of whom are ethnic and racial minorities, routinely encounter levels of air pollution that are higher than average. The extent to which exposure differentials contribute to observed differences in health status by class and race is unknown, but worthy of further investigation. We recommend several steps, all of them feasible and most of them relatively inexpensive, to improve our understanding and ability to address environmental health disparities.

Penetrating pellet fragmentation. A complication of ocular shotgun injury

In three patients who had double-perforating ocular shotgun injuries, a single lead shotgun pellet apparently fragmented after striking the eye, resulting in two separate intraocular impact sites. The importance of detecting double-perforating eye injury and becoming aware of this potential complication with ocular shotgun injuries is emphasized.