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Frameworks for limiting ecosystem exposure to excess nutrients and acidity require accurate and complete deposition budgets of reactive nitrogen (Nr). While much progress has been made in developing total Nr deposition budgets for the U.S., current budgets remain limited by key data and knowledge gaps. Analysis of National Atmospheric Deposition Program Total Deposition (NADP/TDep) data illustrates several aspects of current Nr deposition that motivate additional research. Averaged across the continental U.S., dry deposition contributes slightly more (55%) to total deposition than wet deposition and is the dominant process (>90%) over broad areas of the Southwest and other arid regions of the West. Lack of dry deposition measurements imposes a reliance on models, resulting in a much higher degree of uncertainty relative to wet deposition which is routinely measured. As nitrogen oxide (NOx) emissions continue to decline, reduced forms of inorganic nitrogen (NHx = NH3 + NH4+) now contribute >50% of total Nr deposition over large areas of the U.S. Expanded monitoring and additional process-level research are needed to better understand NHx deposition, its contribution to total Nr deposition budgets, and the processes by which reduced N deposits to ecosystems. Urban and suburban areas are hotspots where routine monitoring of oxidized and reduced Nr deposition is needed. Finally, deposition budgets have incomplete information about the speciation of atmospheric nitrogen; monitoring networks do not capture important forms of Nr such as organic nitrogen. Building on these themes, we detail the state of the science of Nr deposition budgets in the U.S. and highlight research priorities to improve deposition budgets in terms of monitoring and flux measurements, leaf- to regional-scale modeling, source apportionment, and characterization of deposition trends and patterns.

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OBJECTIVES: Some inner-city infants grow to be successful, self-sufficient adults. This study is designed to identify characteristics from early childhood that foster or impede favorable outcomes and are useful for formulation of public policy. POPULATION: 2694 children (G-2s), born 1960 through 1965, to 2307 inner-city women (G-1s) enrolled in the Johns Hopkins Collaborative Perinatal Study. DATA: 1) prospective observations (birth through 8 years) of neurologic and cognitive development, health, behavior, and family and neighborhood socioeconomic characteristics and 2) completed interviews with 1758 G-2s (age 27 to 33) and 1552 G-1s, bridging the period from age 9 to present status. An intergenerational, life course model of development identified significant characteristics and events associated with G-2 outcome (education, physical and mental health, healthy lifestyle, and financial independence of public support, emphasizing educational attainment of a high school diploma or a graduate equivalency degree). Multiple logistic regression equations identified independent, predictive variables during infancy, preschool and early school years, and adolescence. The probability of a good outcome was estimated in the presence of combinations of the six variables most strongly associated with that outcome. RESULTS: Among G-2s, 79% had a successful outcome for education, 60% health, 70% lifestyle, and 76% for financial independence. Black G-2s had more favorable outcomes than white G-2s in education and lifestyle, whites for financial outcome; health did not differ by race. The six variables most predictive of adult education were: G-1 education at G-2 birth and G-2 attainment of honor roll, average or better reading skills at 8 years, avoidance of regular smoking, and pregnancy before age 18, and not repeating a grade in school. CONCLUSIONS: Substantial proportions of inner-city children become successful adults. Attention to improving public education, particularly language and reading skills, and the prevention of smoking and adolescent pregnancy are clearly indicated.

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The implantable cardioverter defibrillator (ICD) is an expensive, widely used device for severe ventricular arrhythmias. Marginal cost-effectiveness analysis is a technique to examine the incremental cost of treatment strategy in relation to its effectiveness. In this study, we used this technique to analyze the cost-effectiveness of the ICD compared with that of electrophysiology (EP)-guided drug therapy and examined ways in which it may be improved. We analyzed Michigan Medicare discharge abstracts (1989 to 1992) and local physician visit, test, and ICD charges. Effectiveness was from 218 previously described patients with ICDs in whom the time of first event (first appropriate shock or death) was determined and presumed to represent "control" (EP-guided drug therapy) mortality. We assumed a 4-year life cycle for the ICD generator and 3.4% operative mortality and used a 5% discount to prevent value. Data were analyzed in a 1-month cycle Markov decision model over a 6-year horizon, and results were updated to 1993 dollars. ICD effectiveness was an increase in discounted mean life expectancy of 1.72 years. Cost-effectiveness was $31,100/year of life saved (YLS). Results were minimally or modestly sensitive to variations in preoperative mortality; resource use; consideration only of patients with ICDs who were receiving any antiarrhythmic drug or specifically amiodarone; and to a decrease in the percentage of first shocks that would equal death without the ICD until the assumed percentage decreased to < 38%. At ejection fraction of < 0.25 and > or = 0.25, cost-effectiveness was $44,000/YLS and $27,200/YLS, respectively, and without preimplant EP study was $18,100/ YLS.(ABSTRACT TRUNCATED AT 250 WORDS)

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The protective effect of nicardipine (1 and 4 microM) against reoxygenation injury was studied in an unstimulated rat single myocyte oxygen paradox model in comparison with control (no drug) or nifedipine (1 microM). Either concentration of nicardipine was strongly protective, approximately doubling the duration of ATP depletion (rigor) that cells could withstand without undergoing hypercontracture when reoxygenated. Nifedipine (1 microM), which matched the negative inotropic effect of nicardipine (4 microM) (as measured by extent of shortening when stimulated), had no protective effect against reoxygenation injury. Neither drug affected the time to rigor, which is a measure of the rate at which the resting cell consumes its endogenous glycogen stores during anaerobic metabolism. Intracellular calcium, measured with the fluorescent probe indo-1, which partitions into both cytosol and mitochondria, rose progressively throughout the rigor period. This rise in calcium was almost totally suppressed by nicardipine (1 microM) but was unaffected by nifedipine. We conclude that nicardipine possesses a direct protective effect on the myocardium not shared by all dihydropyridines. This effect is associated with the prevention of intracellular, and probably mitochondrial, calcium loading but is probably not due to blockade of the L-type calcium channel or reduction of metabolic rate.

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A prospective, randomized, clinical trial was conducted to investigate whether a postpartum visit between a mother and her neonate's future primary care provider combined with telephone access would improve health care utilization, enhance identification of the provider as a source of advice, increase maternal knowledge of infant care, and decrease maternal anxiety and depression. Of 251 mother-neonate pairs, 122 were randomized to the control group and 129 to the intervention group. Outcome variables included health care utilization and results of maternal interviews. More mothers in the intervention group made a scheduled clinic visit in the first 30 days (P = .003), were more likely to seek some form of care at the clinic (P = .006), and tried to reach their physician by phone more often than the control group (P less than .001). There were no differences between the groups' emergency room utilization, the percent who received immunizations by 90 days of age, maternal knowledge of infant care, maternal anxiety, or postpartum depression. The intervention succeeded in improving some measures of health care utilization and results suggest that the relationship between the mother and clinician was strengthened.

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BACKGROUND: Two hundred eighteen patients were evaluated in a two-phase approach (time to first appropriate discharge, survival after discharge) to identify factors that may be related to maximal benefit derived from use of an automatic implantable cardioverter-defibrillator (AICD). METHODS AND RESULTS: One hundred ninety-seven patients survived implantation of AICD, with or without concomitant cardiac surgery. One hundred five patients had an AICD discharge associated with syncope, presyncope, documented sustained ventricular tachycardia or fibrillation, or sleep at 9.1 +/- 11.1 months after implantation. Patients survived 23.8 +/- 18.0 months after AICD discharge. Left ventricular dysfunction (p = 0.008 for ejection fraction less than 25%) was associated with earlier AICD discharge and shortened survival after AICD discharge (p = 0.008 for ejection fraction less than 25%; p = 0.01 for New York Heart Association functional class III and IV). beta-Blocker administration (p = 0.006) and coronary bypass surgery (p = 0.06) were associated with later AICD discharge. Coronary bypass surgery (p = 0.035) but not beta-blockers was associated with more prolonged survival after AICD discharge. CONCLUSIONS: These data suggest that a relatively easy algorithm can be applied to predict which patient will benefit most from AICD implantation.

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To evaluate the effect of long-term bronchodilator therapy in CF patients with demonstrated bronchial hyperresponsiveness, we first performed methacholine challenges to determine responsiveness, then entered 27 patients (16 methacholine responders and 11 nonresponders) into a two-month double-blind crossover trial of albuterol, 90 micrograms by inhalation four times a day vs placebo. Among the responders, daily PEFR measures improved significantly more during treatment with albuterol (12 +/- 32 L/min) than with placebo (-0.4 +/- 19 L/min; p less than 0.05). In addition, a clinically important level of improvement in PEFR (15 percent increase) was reached significantly more frequently in the responders. Methacholine nonresponders had no change in PEFR on either albuterol or placebo. Daily symptom scores as well as spirometry measurements at biweekly visits did not show significant changes. We conclude that long-term therapy with inhaled albuterol improves lung function in CF patients, but only in those with bronchial hyperresponsiveness as demonstrated by methacholine challenge.

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We tested the hypothesis that antihistamine-decongestant combinations cause no clinically significant relief of the symptoms of upper respiratory tract infections in young children by randomly assigning 96 children to one of three treatment groups: antihistamine-decongestant, placebo, and no treatment. There were no differences among the three study groups in the proportion of children considered "better" overall by the parent 48 hours after the initial assessment (drug, 67%; placebo, 71%; no treatment, 57%; p = 0.53). There were no differences among groups in individual or composite symptom score changes. Two thirds of parents whose children were eligible for the drug trial believed that their child needed medicine for cold symptoms. In the proportion of parents believing that their child needed medicine, there was no difference between those who consented to participate and those who refused. Parents who wanted medicine at the initial visit reported more improvement at follow-up, regardless of whether the child received drug, placebo, or no treatment. We conclude that there is no clinically significant improvement in symptoms of upper respiratory tract infection, including no significant placebo effect, in young children for whom an antihistamine-decongestant is prescribed.

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We conducted a case-control study to examine the correlates of emergency room use in the first year of life, particularly the role of parental health beliefs, among the families of inner-city children enrolled in a hospital-based primary care program. Data was collected by structured interviews and by medical record review. Emergency room users were more likely to have single mothers and to have acute, recurrent medical conditions than were non-users. Health beliefs differed between groups by maternal report of worry about the kinds of illnesses that her child acquires. Emergency room use was predicted by: maternal marital status, maternal worry and concern that illness interferes with her child's activity, acute recurrent illnesses, hospitalization. This model may be applicable to other populations in designing intervention strategies to modify emergency room utilization.

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To explore some determinants of physicians' decisions to change practice habits, we posed three questions: To what extent are some particular innovations diffused among office-based primary care physicians? What characterizes the physicians who have adopted these innovations? And, what caused them to change their behavior and adopt the innovations? Three "markers," recent innovation in medical practice, were chosen using an expert consensus technique. A telephone survey of 200 office-based pediatricians was conducted, and the physicians were asked whether or not they used the following three innovations in medical practice: continuous rather than intermittent phenobarbital for the prevention of febrile seizures, glycosylated hemoglobin measurement in the management of diabetes, and slow release theophylline in the management of asthma. The questionnaire was completed by 156 pediatricians. Of the 110 pediatricians who cared for diabetics, 73% used glycosylated hemoglobin measurement; of the 145 who saw patients with febrile seizures, 77% prescribed the continuous use of phenobarbital (if they used it at all); and, of the 152 pediatricians who cared for asthmatics, 86% reported using slow-release theophylline. The characteristics significantly associated with using the innovations were board certification, group rather than solo practice, teaching, medically related publications, academic appointment, younger age, and caring for a greater number of patients per week. For two of the innovations, discussion with a colleague was the most important source of information leading to a change of practice. The subjects cited local specialists as the colleagues who most often sparked the adoption of an innovation.

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We evaluated the courses of 115 consecutive cases of pediatric acute leukemia treated with induction chemotherapy. Seventy-two patients developed fever associated with neutropenia; 15 developed systemic fungal infections. We reviewed multiple demographic and treatment characteristics of these patients in an attempt to identify potential risk factors for the development of invasive fungal disease (IFD). Risk factors identified in a univariate analysis included duration of neutropenia after first fever (P less than .0001), diagnosis of acute nonlymphocytic leukemia (ANLL) (P = .003), onset of fever and neutropenia within 5 days of starting induction chemotherapy (P = .009), and multiple (greater than one) surveillance culture sites positive for fungal organisms (P = .02). In a multiple logistic regression analysis, duration of neutropenia (P less than .001) remained a significant risk factor. The study group of patients had a significantly higher risk of fungal infections than a matched group of leukemia patients developing fever with neutropenia due to postremission consolidation chemotherapy (P = .003). In the first 48 patients, 14 (29%) developed IFD. In the subsequent patients (n = 24), intravenous miconazole (5 mg/kg every 8 hours) was begun at the time of the first fever. One of the 24 patients (4%) given miconazole developed IFD. The use of miconazole was a negative risk factor for the development of IFD in univariate (P = .01) and multivariate (P = .05) analysis. We conclude that pediatric leukemia patients who develop fever associated with neutropenia during induction chemotherapy are at high risk for developing IFD. The role of intravenous miconazole at the time of the first fever in this group deserves further study.

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To determine whether intravenous immunoglobulin (IVGG) would be an efficacious adjunct in the treatment of childhood minimal change nephrotic syndrome (MCNS), we enrolled ten patients with frequently relapsing or steroid-dependent MCNS in a double-blind crossover clinical trial. At the time of relapse of the nephrotic syndrome, patients were assigned to treatment with a single outpatient infusion of IVGG (800 mg/kg) or intravenous albumin as a control. The relapse was treated concurrently with standard doses of oral prednisone. At the time of the next relapse, patients who had first received IVGG were treated with albumin, and vice versa. There were no significant differences in the length of remission between the IVGG and albumin treatments. The study had a power of 0.72 to detect a true difference of 45 days between the two therapies. We conclude that in the dose of drug used in this trial, administered at the time of relapse in conjunction with prednisone therapy to children with frequently relapsing or steroid-dependent MCNS, IVGG does not lead to a clinically important extension of the period of remission.

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STUDY OBJECTIVE: To determine whether acetaminophen affects the duration or severity of childhood varicella. DESIGN: Randomized, double-blind, placebo-controlled trial. SETTING: Office- and hospital-based pediatric practices. PATIENTS: Seventy-two children between 1 and 12 years of age entered the study. One child was withdrawn because of high fever, and three children did not complete the study; 31 received placebo and 37 received acetaminophen. INTERVENTIONS: Acetaminophen, 10 mg/kg/dose, was given at 8 AM, 12 PM, 4 PM, and 8 PM for 4 days. Placebo was given to the control group. Itching, appetite, activity, and overall condition were measured for 6 days. The time to last vesicle formation, time to total scabbing, and time to total healing were measured until complete resolution of the exanthem. MEASUREMENTS AND MAIN RESULTS: The following results were better in the placebo group (p less than .05): time to total scabbing 5.6 days (SD 2.5) versus 6.7 days (SD 2.3) in the acetaminophen group, and itching on day 4 in the placebo group (symptom score 2.9 (SD 0.20) vs 2.2 (SD 0.26]. Activity was better in the acetaminophen group on day 2 (3.13 (SD 0.23) vs 2.82 (SD 0.24]. CONCLUSIONS: These results provide evidence that acetaminophen does not alleviate symptoms in children with varicella and may prolong illness.

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The relative prognostic significance of ischemic ST changes on two-lead continuous electrocardiographic (Holter) monitoring in 103 high-risk postinfarction patients was examined. Ischemic ST changes were detected in 30 patients, with a median number of five episodes per day and median total daily duration of 157 minutes. Only one third of these patients reported any angina in the hospital, and 28 of the 30 patients had silent ST changes on Holter monitoring. The remaining 73 patients had no ischemic ST changes on Holter monitoring. At one year, nine (30%) of 30 patients with ischemic ST changes were dead vs only eight (11%) of 73 patients without such changes. Multivariate Cox's hazard function analysis on 18 variables, including age, type of infarction, Lown and Killip class, ejection fraction, and medications, showed that the presence of ST changes on Holter monitoring was a significant predictive variable for one-year mortality in the overall study population and particularly in the subgroup of 59 patients who could not undergo early exercise treadmill testing. Thus, ischemic ST changes on Holter monitoring, the majority of which are silent, occur in nearly one third of high-risk postinfarction patients and are significantly associated with one-year mortality.

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From 1975 to 1983, 240 patients with carcinoma of the prostate, Stages A2 to C, were treated with whole pelvic radiation followed by a 2-week rest and then a reduced field of radiation. The reduced prostatic field was evaluated for adequacy of tumor coverage by CT scan or ultrasound. The local regional control rate was 94%, with a 5-year actuarial survival for all stages of 72%. Severe complications occurred in 3% of patients and moderate complications in 13%. Two major factors that were identified as contributing to the risk of complications included previous or subsequent surgical intervention. Our technique of external beam radiotherapy resulted in a favorable therapeutic ratio, that is, excellent local-regional control with minimal morbidity.

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Antiepileptic medications were discontinued in 88 children with epilepsy of various causes who had been free of seizures for two to four years. The subjects were then followed for six months to five years (mean, 22 months). Sixty-six (75 per cent) remained free of seizures. Electroencephalographic characteristics, type of seizure, and age at onset were important in predicting outcome. Specific electroencephalographic features (such as the presence or absence of slowing or spikes) were more predictive than simple classification of an electroencephalogram as normal or abnormal. A history of complex partial seizures that had been controlled for two years carried a relatively favorable prognosis (P less than 0.05), whereas a history of atypical febrile seizures carried a poor prognosis (P less than 0.05). The variable of a younger age at onset was also associated with a better outcome (P less than 0.05), but only if accompanied by electroencephalographic slowing. Altogether, six variables (the interaction of age at onset with electroencephalographic slowing, electroencephalographic spikes, atypical febrile seizures, complex partial seizures, electroencephalographic slowing, and electroencephalographic change) were statistically significant (P less than 0.05) in predicting outcome. We conclude that in most children with epilepsy who have been free of seizures for two or more years, antiepileptic medications can safely be discontinued, and that it is possible to predict reasonably well which children will remain free of seizures.

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We studied metabolic, endocrine, and environmental factors in 59 women who had delivered a child with cleft lip with or without cleft palate (CL +/- CP) and compared these values with those of 56 mothers of unaffected children. There was no significant difference between the two groups with respect to race, age, weight, height, education, parity, menstrual history, medical illnesses, or the use of contraceptives, tobacco, alcohol, or caffeine. All patients had a normal XX karyotype confirmed by the fluorescent banding technique. The two groups demonstrated no significant difference in test results of serum chemistries, glucose tolerance, serum or erythrocyte folate, vitamin A, carotene, corticoids, prolactin T4, free T4, urine 17-ketosteroids, 17-hydroxysteroids, total estrogens, or pregnanediol. Urinalyses revealed no group differences in the presence of barbiturates, amphetamines, salicylates, or benzodiazepines. The percentage of immunologic studies reflecting susceptibility to toxoplasmosis, rubella, cytomegalic inclusion disease, and herpes was not different between the two groups. The only statistically significant metabolic differences between the two groups were serum alkaline phosphatase, creatinine, creatinine clearance, and creatinine clearance/m2. Phenytoin pharmacokinetics and urinary metabolic patterns were compared in a subgroup of ten mothers of affected children and ten mothers from the control group. No significant differences were observed. However, a brief course of phenytoin treatment induced a greater inhibition of the folate tolerance test in controls than in mothers of children with clefts.

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