Accumulation of behavioral validation evidence for physical activity stage of change.

Objective: The purpose of this study was to accumulate behavioral validity evidence for physical activity Stage of Change (SOC).

Design: Nine studies used a common physical activity SOC measure and examined self-report, objective, and performance physical activity indicators to accumulate behavioral validity evidence for SOC. Type of measure, the strength of the expected relationship between the measure and SOC, and the predicted SOC differences were examined.

The PHLAME (Promoting Healthy Lifestyles: Alternative Models' Effects) firefighter study: outcomes of two models of behavior change.

Objective: PHLAME's (Promoting Healthy Lifestyles: Alternative Models' Effects) objective was to assess and compare two means to promote healthy lifestyles.

Methods: Prospective trial among 599 firefighters randomized by station to 1) team-centered curriculum, 2) one-on-one motivational interviewing (MI), and 3) controls. Assessment included dietary behavior, physical activity, weight, and general well-being at baseline and 12 months.

A new tool to assess treatment fidelity and evaluation of treatment fidelity across 10 years of health behavior research.

A. Bellg, B. Borrelli, et al.

MR angiography of aortoiliac occlusive disease: a phase III study of the safety and effectiveness of the blood-pool contrast agent MS-325.

Purpose: To evaluate prospectively the safety and effectiveness of aortoiliac magnetic resonance (MR) angiography enhanced with MS-325 (gadofosveset trisodium) at a dose of 0.03 mmol/kg; effectiveness was defined as accuracy relative to the reference standard, conventional angiography.

Materials And Methods: Study was approved by institutional review boards of participating institutions, and required national approvals were obtained.

Examples of implementation and evaluation of treatment fidelity in the BCC studies: where we are and where we need to go.

Treatment fidelity plays an important role in the research team's ability to ensure that a treatment has been implemented as intended and that the treatment has been accurately tested. Developing, implementing, and evaluating a treatment fidelity plan can be challenging. The treatment fidelity workgroup within the Behavior Change Consortium (BCC) developed guidelines to comprehensively evaluate treatment fidelity in behavior change research.

Physical activity staging distribution: establishing a heuristic using multiple studies.

The purpose of this study was to identify the population prevalence across the stages of change (SoC) for regular physical activity and to establish the prevalence of people at risk. With support from the National Institutes of Health, the American Heart Association, and the Robert Wood Johnson Foundation, nine Behavior Change Consortium studies with a common physical activity SoC measure agreed to collaborate and share data. The distribution pattern identified in these predominantly reactively recruited studies was Precontemplation (PC) = 5% (+/- 10), Contemplation (C) = 10% (+/- 10), Preparation (P) = 40% (+/- 10), Action = 10% (+/- 10), and Maintenance = 35% (+/- 10).

Motivational interviewing in community-based research: experiences from the field.

Motivational Interviewing (MI) has been established as an effective psychotherapeutic treatment for problem drinking in clinical settings. Consequently, there is a growing interest in applying MI to facilitate change across other health behaviors, such as tobacco use, eating habits, and physical activity in a variety of community-based research settings. These extended applications pose new challenges regarding implementation and evaluation.

The PHLAME firefighters' study: feasibility and findings.

Objective: To assess efficacy of 2 worksite health promotion interventions.

Methods: Randomly assign 3 fire stations to (a) team-based curriculum, (b) individual counselor meetings, and (c) control.

Results: Both interventions were feasible and acceptable, and they resulted in significant reductions in LDL cholesterol.

Promoting Healthy Lifestyles: Alternative Models' Effects (PHLAME).

The Promoting Healthy Lifestyles: Alternative Models' Effects (PHLAME) study evaluates the efficacy of two intervention strategies for improving nutrition and physical activity practices in fire fighters: a team-centered program and a one-on-one format targeting the individual. PHLAME compares these two behavior change models (the team-based versus the one-on-one approaches) against a usual-care control group. As a group, fire fighters have a concentration of the same harmful behaviors and health risks commonly afflicting the US population.

Quantitative MR in the diagnosis of multiple sclerosis.

In patients with multiple sclerosis (MS), the apparently uninvolved cerebral white matter between demyelinated plaques may have biochemical abnormalities. To what degree the changes in the white matter contribute to symptomatology in MS is unknown. In 39 patients with multiple sclerosis, and in 39 age-matched nondiseased volunteers, T1 and T2 were calculated from spin-echo images in four regions of apparently uninvolved white matter.

T1 and T2 in the cerebrum: correlation with age, gender, and demographic factors.

The authors measured the T1 and T2 of cerebral tissue in 164 volunteers aged 5-90 years and correlated T1 and T2 with age, gender, and various demographic variables. A weak correlation with statistical significance was found between age and T1 and T2 in white and gray matter structures. The T1 and T2 in the telencephalon increased by about 0.

Contrast enhancement in spinal MR imaging.

We evaluated 44 patients with suspected spinal tumors or previous laminectomies with gadolinium-DTPA MR imaging in order to characterize the enhancement in normal, postoperative, and neoplastic intraspinal tissue. Using the signal intensity of CSF as an internal control, we calculated the percentage increase in signal intensity from pre- to postgadolinium studies. Tumors (astrocytoma, ependymoma, schwannoma) enhanced 70-350%; epidural scar, normal epidural venous plexus, and dorsal root ganglion enhanced up to 200%.

T1 and T2 measurements on a 1.5-T commercial MR imager.

In order for relaxation times to be used in clinical diagnosis, the precision of the measurement must be determined. The authors measured T1, T2, and proton density in a phantom and in human volunteers to determine the reproducibility of the method. The coefficient of variance of T1 measurements in the phantom during a 15-month period with two software upgrades was 5%.

Truncation artifact in MR images of the intervertebral disk.

A cadaver's vertebral column, a phantom, and a volunteer were imaged on a 1.5-T MR scanner to study the thin, uniform, dark, transverse lines that characterize some intervertebral disks. An artifactual dark line appears when the field of view (FOV) and matrix steps (n) are chosen so that d = FOV/n, where d equals the intervertebral disk height, or spacing between phantom vertebrae.

Sensitivity of Gd-DTPA-enhanced MR imaging of benign extraaxial tumors.

The effect of gadolinium diethylenetriaminepentaacetic acid (DTPA) on the sensitivity of cranial magnetic resonance (MR) imaging was measured in a prospective blinded study. Twenty-two consecutive patients with benign extraaxial tumors underwent MR imaging on a 1.5-T system without and with intravenous administration of Gd-DTPA.

"Truncation" artifact in MR images of the internal auditory canal.

Dry skulls and a phantom were studied to determine whether an intracanalicular dark band in MR images of some acoustic neuromas could be artifactual. A "truncation" artifact was detected in the internal auditory canals of the dry skulls and in a simulated internal auditory canal of the phantom when the width of the canal approximately equaled 4 X (field of view) /N, where N equals 128 or 256, depending on the number of gradient steps chosen. The "truncation" artifact should not be confused with CSF between normal nerves when a canal contains tumor.

Benign extraaxial tumors: contrast enhancement with Gd-DTPA.

Meningiomas, acoustic neuromas, and other benign extraaxial tumors have little contrast with adjacent brain tissue on conventional magnetic resonance (MR) images. The contrast enhancement produced by intravenous administration of 0.1 mmol/kg of gadolinium-DTPA in these tumors was measured on T1 MR images.

Methodology for the measurement and analysis of relaxation times in proton imaging.

Measurements of proton T1 and T2 were performed on GdCl3 solutions (20 less than T2 less than 500 msec, 90 less than T1 less than 1000 msec) on large-bore NMR imaging systems operating at 1.0T and 1.5T.

Reproducibility of relaxation and spin-density parameters in phantoms and the human brain measured by MR imaging at 1.5 T.

The reproducibility of T1, T2, and proton density, measured in phantoms and the human brain was evaluated by proton imaging techniques. The sequence used to derive T1 and density values was a multiple-saturation recovery which consists of four pairs of 90 degrees pulses, followed by a 180 degrees phase reversal pulse, generating four T1-weighted images. T2 was derived from a multiple-echo sequence, generating four T2-weighted images.

Cranial tissues: normal MR appearance after intravenous injection of Gd-DTPA.

The effect of intravenously administered gadolinium DTPA on signal intensity of normal intracranial structures was analyzed in 25 patients. Magnetic resonance (MR) image enhancement with Gd-DTPA differs from image enhancement on computed tomography with aqueous iodinated contrast media. Marked contrast enhancement owing to Gd-DTPA was observed in the pituitary gland, infundibulum, cavernous sinus, cranial nerves, choroid plexus, and nasal mucosa.

Quantification of contrast in clinical MR brain imaging at high magnetic field.

The relative contrast between two tissues in a magnetic resonance (MR) image is shown to be quantifiable for any combination of pulse timing parameters, provided the intrinsic parameters are known. Based on multiple inversion-recovery and spin echo images, a region-of-interest T1, T2 and density analysis was conducted at 1.4T in selected patients with diagnosed neuropathology for various brain tissues.

Mechanisms of contrast in NMR imaging.

Nuclear magnetic resonance pixel intensity and contrast-to-noise has been computed and presented in graphical form for various tissues in the normal central nervous system, on the assumption that the signal intensity is proportional to the macroscopic transverse spin magnetization at the time of detection. T1, T2, and spin density values were experimentally determined using chi-square minimization techniques. Additionally, spin density was derived from partial saturation scans obtained with a long repetition time compared with the spin-lattice relaxation time.

Comparative effects of hexachloro- and hexabromobenzene on hepatic monooxygenase activity of male and female rats.

Male and female Sprague-Dawley rats were treated once with either crude or purified hexachlorobenzene (HCB) or crude or purified hexabromobenzene (HBB) at 150 mg/kg, intraperitoneally. Examination of hepatic microsomes 4 d later revealed an increase in cytochrome P-450 levels in both HCB- and HBB-pretreated animals. HBB produced a slight but statistically significant hypsochromic shift.

Further structural analysis of rat liver microsomal metabolites of 2-methylnaphthalene.

The oxidative metabolites of 2-methylnaphthalene (2-MN) were extracted from rat liver microsome suspensions. One monohydroxylated and three isomeric dihydrodiol metabolites of 2-MN were isolated and purified by HPLC. The metabolites were characterized by GC-MS together with 1H Fourier transform (1HFT) NMR.