Recruiting the ABCD sample: Design considerations and procedures.

The ABCD study is a new and ongoing project of very substantial size and scale involving 21 data acquisition sites. It aims to recruit 11,500 children and follow them for ten years with extensive assessments at multiple timepoints. To deliver on its potential to adequately describe adolescent development, it is essential that it adopt recruitment procedures that are efficient and effective and will yield a sample that reflects the nation's diversity in an epidemiologically informed manner. Here, we describe the sampling plans and recruitment procedures of this study. Participants are largely recruited through the school systems with school selection informed by gender, race and ethnicity, socioeconomic status, and urbanicity. Procedures for school selection designed to mitigate selection biases, dynamic monitoring of the accumulating sample to correct deviations from recruitment targets, and a description of the recruitment procedures designed to foster a collaborative attitude between the researchers, the schools and the local communities, are provided.

MiR203 mediates subversion of stem cell properties during mammary epithelial differentiation via repression of ΔNP63α and promotes mesenchymal-to-epithelial transition.

During reproductive life, the mammary epithelium undergoes consecutive cycles of proliferation, differentiation and apoptosis. Doing so relies on the retained proliferative capacity, prolonged lifespan and developmental potency of mammary stem cells (MaSCs). ΔNp63α, the predominant TP63 isoform in mammary epithelia, is robustly expressed in MaSCs and is required for preservation of self-renewing capacity in diverse epithelial structures. However, the mechanism(s) underlying subversion of this activity during forfeiture of self-renewing capacity are poorly understood. MicroRNAs (miRNAs) govern critical cellular functions including stem cell maintenance, development, cell cycle regulation and differentiation by disrupting translation of target mRNAs. Data presented here indicate that expression of miR203, a miRNA that targets ΔNp63α and ΔNp63ß is activated during luminal epithelial differentiation and that this pattern is observed in the murine mammary hierarchy. In addition, we present evidence that the transcription factor Zeb1 represses miR203 expression, thus enhancing ΔNp63α protein levels. Furthermore, ectopic miR203 suppresses ΔNp63α expression, proliferation and colony formation. The anti-clonogenic effects mediated by miR203 require suppression of ΔNp63α. In addition, ectopic miR203 promotes mesenchymal-to-epithelial transition and disrupts activities associated with epithelial stem cells. These studies support a model in which induction of miR203 mediates forfeiture of self-renewing capacity via suppression of ΔNp63α and may also have anti-tumorigenic activity through its reduction of EMT and cancer stem cell populations.

Cigarette smoking and the incidence of Parkinson's disease in two prospective studies.

An inverse association between cigarette smoking and idiopathic Parkinson's disease has been reported in several retrospective studies, but prospective evidence is available only for men. We assessed the association between the incidence of Parkinson's disease and smoking in two large prospective cohort studies comprising men and women. New cases of Parkinson's disease were identified in the Nurses' Health Study for 1976-1996, and in the Health Professionals Follow-up Study for 1986-1996. Smoking history was assessed at baseline and updated on subsequent biennial questionnaires. In women, the age-adjusted rate ratios (95% confidence intervals) for Parkinson's disease relative to never-smokers were 0.7 (0.5, 1.0) for past smokers, and 0.4 (0.2, 0.7) for current smokers. In men, the age-adjusted rate ratios for Parkinson's disease relative to never-smokers were 0.5 (0.4, 0.7) for past smokers, and 0.3 (0.1, 0.8) for current smokers. In both cohorts, the strength of the association decreased with time since quitting (among past smokers), increased with number of cigarettes per day (among current smokers), and increased with pack-years of smoking. These prospective findings confirm that an inverse association between smoking and the incidence of Parkinson's disease exists in both men and women.

Onset and duration of analgesia of diclofenac potassium in the treatment of postepisiotomy pain.

A double-blind, placebo-controlled, parallel group study was performed to compare the analgesic efficacy of diclofenac potassium (25, 50, or 100 mg) with that of aspirin (650 mg), or placebo. Two hundred fifty-five inpatients with severe postepisiotomy pain were randomly assigned to receive a single oral dose of one of the four active treatments or placebo. Analgesia was assessed over an 8-hour period. Treatments were compared on the basis of standard scales for pain intensity and relief and a number of derived variables based on these data, as well as two global ratings of the study medication. All active treatments were effective analgesics statistically superior to placebo for many hourly and summary measures, including the global ratings. Diclofenac potassium (50 and 100 mg) was statistically significantly superior to aspirin at half-hour and for many other hourly scores from hour 3 on. The 4- and 8-hour sum of the pain intensity difference and total pain relief scores reflected the superiority of diclofenac potassium to aspirin. In addition, the 100-mg dose was significantly more efficacious than the 25-mg dose of diclofenac potassium. The probability of obtaining onset was significantly better for all active treatments than for placebo; however, the median onset times were similar for all treatments. The duration of effect, as measured by mean pain intensity difference and relief scores, was better for diclofenac potassium than aspirin, and these differences were significant for the 50- and 100-mg doses. The probability of pain returning to baseline was significantly less for the diclofenac groups than for placebo or aspirin groups. In addition, significantly fewer patients treated with diclofenac (25, 50, or 100 mg) or aspirin (650 mg) required remedication during the 8-hour study period as compared with those treated with placebo. Diclofenac potassium is an effective analgesic in the range of aspirin (650 mg) at the 25-mg dose and superior in efficacy and longer lasting than aspirin at the 50- and 100-mg doses. The onset of analgesia was similar for aspirin and diclofenac potassium.

Analgesic oral efficacy of tramadol hydrochloride in postoperative pain.

Tramadol hydrochloride is a synthetic opiate agonist with a plasma elimination half-life of 5 to 6 hours and peak plasma levels at about 1 1/2 hours. It derives its activity from attachment to the mu-receptor and blockage of norepinephrine reuptake. The purpose of this single-dose, double-blind, placebo-controlled study was to determine the analgesic effectiveness of an oral administration of two dose levels of tramadol hydrochloride (75 or 150 mg) compared with the combination of 650 mg acetaminophen plus 100 mg propoxyphene napsylate in 161 patients with severe postoperative pain after cesarean section. Analgesia was assessed over a 6-hour period. Treatments were compared on the basis of standard scales for pain intensity and relief and a number of derived variables based on these data. A global rating of the study medication was also used to compare treatments. The three active treatments were effective analgesics, statistically superior to placebo for many hourly and summary measures. A dose response was seen between the two tramadol doses, with the 150 mg dose providing significantly greater analgesia over the lower dose. The 75 mg dose of tramadol was generally more effective than the acetaminophen-propoxyphene combination after hour 2, and significantly so for some hourly time points, as well as for the global rating of the medication. The 150 mg dose of tramadol was significantly more effective than the acetaminophen-propoxyphene combination from hour 2 through hour 6 for the sum of pain intensity differences and total pain relief scores, as well as for the global rating of the medication. Tramadol hydrochloride at both dose levels is an effective analgesic agent and at 150 mg is statistically superior to the acetaminophen-propoxyphene combination. No serious adverse effects were observed; however, dizziness was more frequently reported with 150 mg tramadol.

Determination of kanamycin concentration in serum by substrate-labeled fluorescent immunoassay.

A homogeneous substrate-labeled fluorescent immunoassay was developed for the measurement of kanamycin concentrations in serum. A fluorogenic drug reagent (FDR) (beta-galactosyl-umbelliferone-tobramycin) was prepared that is nonfluorescent under the conditions of the assay but is hydrolyzed upon catalysis by beta-galactosidase to yield a fluorescent product. Binding of the FDR to the antiserum to kanamycin prevented enzyme hydrolysis. The fixed level of FDR in the assay competed with kanamycin in the sample for a limited number of antibody-binding sites. Unbound FDR was hydrolyzed by beta-galactosidase to release a fluorescent product that is proportional to the kanamycin concentration in the sample. The assay exhibited good sensitivity, precision, and accuracy and correlated well with other methods.

Plasma human placental lactogen, oxytocinase, and placental phosphatase in normal and toxemic pregnancies.

A total of 625 serum samples were drawn from 400 normal and 225 hypertensive toxemic pregnant women. Each sample was simultaneously assayed for its human placental lactogen (HPL), oxytocinase (O), and placental phosphatase (PP) concentration. In addition, accurate placental and infant birth weights were determined in those cases where the serum sample was obtained within 14 days of delivery. The results showed a significant rise and correlation of each of the three proteins with increasing weeks of gestation. Although the infant birth weight was unrelated to the serum level of the three proteins, both the HPL and O concentrations were significantly correlated with the placental weight in the normal pregnancies. In both types of pregnancies, the concentration of O was significantly related to that of PP and this was also true for HPL and O and HPL and PP. In all instances O was more strongly related than PP. In the toxemic pregnancies there was a higher O and lower PP level than in normal gestations. These data suggest that placental enzyme measurements, especially O, could be clinically helpful in monitoring high-risk pregnancies.