Searching for moderators and mediators of pharmacological treatment effects in children and adolescents with anxiety disorders

OBJECTIVE: To examine whether age, gender, ethnicity, type of anxiety disorder, severity of illness, comorbidity, intellectual level, family income, or parental education may function as moderators and whether treatment adherence, medication dose, adverse events, or blinded rater's guess of treatment assignment may function as mediators of pharmacological treatment effect in children and adolescents with anxiety disorders. METHOD: The database of a recently reported double-blind placebo-controlled trial of fluvoxamine in 128 youths was analyzed. With a mixed-model random-effects regression analysis of the Pediatric Anxiety Rating Scale total score, moderators and mediators were searched by testing for a three-way interaction (strata by treatment by time). A two-way interaction (strata by time) identified predictors of treatment outcome. RESULTS: No significant moderators of efficacy were identified, except for lower baseline depression scores, based on parent's (but not child's) report, being associated with greater improvement (p < .001). Patients with social phobia (p < .05) and greater severity of illness (p < .001) were less likely to improve, independently of treatment assignment. Blinded rater's guess of treatment assignment acted as a possible mediator (p < .001), but improvement was attributed to fluvoxamine, regardless of actual treatment assignment. Treatment adherence tended to be associated (p = .05) with improvement. CONCLUSIONS: In this exploratory study, patient demographics, illness characteristics, family income, and parental education did not function as moderators of treatment effect. Social phobia and severity of illness predicted less favorable outcome. Attribution analyses indicated that study blindness remained intact. The presence of concomitant depressive symptoms deserves attention in future treatment studies of anxious children.     

8-Br-cAMP和槲皮素诱导Eca-109细胞p16基因启动子DNA结合蛋白的定位研究

目的：探讨8-Br-cAMP和槲皮素(quercetin)诱导的Eca-109细胞p16基因启动子特异性结合的序列特异性DNA结合蛋白(DBP)的定位。方法：应用DBP定位改进方法,以制备的特异性DNA探针检测目的DBP在细胞内的定位;以免疫细胞化学技术,检测纲胞PCNA免疫反应性,作为肿瘤细胞恶性程度生物标志。结果：DBP定位信号以胞核为主,胞质有阳性信号的细胞．胞膜也呈阳性信号;2实验组信号比对照组强;各组信号均以大细胞更强;PCNA免疫细胞化学阳性呈棕黄色颗粒,主要位于胞核．对照组强于实验组。各组均以大细胞阳性信号更强。结论：2实验组与p16基因启动子结合的DBP主要位于胞核,但核外存在结合潜力的蛋白质。2实验组：PCNA免疫反应性均下降。捉示这些与p16基因启动子区结合的DBP在一定程度上可诱导细胞恶性逆转化。     

Effect of parenteral glutamine supplementation on plasma amino acid concentrations in extremely low-birth-weight infants

BACKGROUND: Glutamine is one of the most abundant amino acids in both plasma and human milk and may be conditionally essential in premature infants. However, glutamine is not provided by standard intravenous amino acid solutions. OBJECTIVE: We assessed the effect of parenteral glutamine supplementation on plasma amino acid concentrations in extremely low-birth-weight infants receiving parenteral nutrition (PN). DESIGN: A total of 141 infants with birth weights of 401-1000 g were randomly assigned to receive a standard intravenous amino acid solution that did not contain glutamine or an isonitrogenous amino acid solution with 20% of the total amino acids as glutamine. Blood samples were obtained just before initiation of study PN and again after the infants had received study PN (mean intake: 2.3 +/- 1.0 g amino acids x kg(-1) x d(-1)) for approximately 10 d. RESULTS: Infants randomly assigned to receive glutamine had mean plasma glutamine concentrations that increased significantly and were approximately 30% higher than those in the control group in response to PN (425 +/- 182 and 332 +/- 148 micromol/L for the glutamine and control groups, respectively). There was no significant difference between the 2 groups in the relative change in plasma glutamate concentration between the baseline and PN samples. In both groups, there were significant decreases in plasma phenylalanine and tyrosine between the baseline and PN samples; the decrease in tyrosine was greater in the group that received glutamine. CONCLUSIONS: In extremely low-birth-weight infants, parenteral glutamine supplementation can increase plasma glutamine concentrations without apparent biochemical risk. Currently available amino acid solutions are likely to be suboptimal in their supply of phenylalanine, tyrosine, or both for these infants.     

Medicare breast surgery fees and treatment received by older women with localized breast cancer

OBJECTIVE: To determine whether area-level Medicare physician fees for mastectomy and breast conserving surgery were associated with treatment received by Medicare beneficiaries with localized breast cancer and to compare these results with an earlier analysis conducted using small areas (three-digit zip codes) as the unit of observation. DATA SOURCE: Medicare claims and physician survey data for a national sample of elderly (aged 67 or older) Medicare beneficiaries with localized breast cancer treated in 1994 (unweighted n = 1,787). STUDY DESIGN: Multinomial logistic regression analysis was used to estimate a model of treatment received as a function of Medicare fees, controlling for other area economic factors, patient demographic and clinical characteristics, physician experience, and region. PRINCIPAL FINDINGS: In 1994, average Medicare fees (adjusted for the effects of modifiers and procedure mix) for mastectomy (MST) and breast conserving surgery (BCS) were 904 dollars and 305 dollars, respectively. Holding other fees and factors fixed, a 10 percent increase in the BCS fee increased the odds of breast conserving surgery with radiation therapy relative to mastectomy to 1.34 (p = 0.02), while a 10 percent decrease in the MST fee increased the odds of breast conserving surgery with radiation therapy to 1.86 (p < 0.01). CONCLUSIONS: Among older women with localized breast cancer, financial incentives appear to influence the use of mastectomy and breast conserving surgery with radiation therapy. This finding is consistent with the hypothesis that physicians are responsive to financial incentives when the alternative procedures have clinically equivalent outcomes and the patient's clinical condition does not dominate the treatment choice. We also find that the fee effects derived from this analysis of individual data with more precise measurement of both diagnosis and treatment are qualitatively similar to the results of the small-area analysis. This suggests that the earlier study was not severely affected by ecological bias or other data limitations inherent in Medicare claims data.     

Evaluation of occult acetaminophen hepatotoxicity in hospitalized children receiving acetaminophen. Pediatric Pharmacology Research Unit Network

The safety of repeated doses of acetaminophen in ill children with the potential of reduced glutathione stores has been questioned. This study measured hepatic transaminases in children and adolescents (n=100) who received > or = 6 therapeutic doses of acetaminophen over a 48-hour period of hospitalization. Acetaminophen-protein adducts were measured in a cohort of subjects with hepatic transaminase elevation (n=8) and in those (n=10) receiving concurrent drug therapy with agents that induce the cytochrome P450 enzymes involved in acetaminophen metabolism. Acetaminophen-protein adducts were not detected in this cohort of 18 subjects. Based on this pilot study, the routine use of acetaminophen at therapeutic doses in ill, hospitalized children and adolescents appears safe.     

Home apnea monitor use in preterm infants discharged from newborn intensive care units

PURPOSE: To identify current factors associated with home apnea monitor use in preterm infants and to determine whether home monitor use was associated with a shorter length of hospital stay. SETTING: We evaluated neonates who were < or =34 weeks' estimated gestational age and admitted for neonatal intensive care. We excluded neonates with congenital anomalies, neonates transferred out before discharge, and neonates who died. METHODS: Using a database created with a computer-assisted tool that generates hospital notes, we reviewed the epidemiology of monitor use. Differences between neonates sent home with an apnea monitor and those who were not were evaluated by using stepwise logistic regression analysis to identify which factors were independently associated with a neonate being discharged with a monitor. RESULTS: We studied 14,532 neonates; 1588 (11%) were sent home with monitors and 12,944 (89%) were not. The most important variables associated with being discharged with a monitor were site of care and a diagnosis of apnea. Site variation remained significant when adjusted for gestational age, diagnosis of apnea, and a history of use of methylxanthines. When corrected for gestational age, monitor use was not associated with shorter hospital stays. CONCLUSION: The data suggest that monitor use is more dependent on physician preference than medical indication and is not associated with earlier hospital discharge.     

Mosquito surveillance and polymerase chain reaction detection of West Nile virus, New York State

West Nile (WN) virus was detected in the metropolitan New York City (NYC) area during the summer and fall of 1999. Sixty-two human cases, 7 fatal, were documented. The New York State Department of Health initiated a departmental effort to implement a statewide mosquito and virus surveillance system. During the 2000 arbovirus surveillance season, we collected 317,676 mosquitoes, submitted 9,952 pools for virus testing, and detected 363 WN virus-positive pools by polymerase chain reaction (PCR). Eight species of mosquitoes were found infected. Our mosquito surveillance system complemented other surveillance systems in the state to identify relative risk for human exposure to WN virus. PCR WN virus-positive mosquitoes were detected in NYC and six counties in the lower Hudson River Valley and metropolitan NYC area. Collective surveillance activities suggest that WN virus can disperse throughout the state and may impact local health jurisdictions in the state in future years.