Insulin signaling through insulin receptor substrate 1 and 2 in normal liver development.

Background & Aims: The insulin growth factor signal transduction pathway is an important regulator of adult hepatocyte proliferation. The purpose of this study was to determine the roles of the insulin receptor substrate (IRS-1 and IRS-2)-mediated growth cascades in rapidly growing fetal rat liver.

Methods: We determined the expression and tyrosyl phosphorylation of the insulin receptor beta subunit (IRbeta), IRS-1 and IRS-2, the binding of phosphatidylinositol 3-kinase (PI3K), and activation of the mitogen-activated protein kinase (MAPK) pathway in the presence or absence of insulin stimulation in vivo during development and in the adult liver.

Ratio between forced expiratory flow between 25% and 75% of vital capacity and FVC is a determinant of airway reactivity and sensitivity to methacholine.

Study Objective: The ratio between forced expiratory flow between 25% and 75% of vital capacity (FEF(25-75)) and FVC is thought to reflect dysanapsis between airway size and lung size. A low FEF(25-75)/FVC ratio is associated with airway responsiveness to methacholine in middle-aged and older men. The current study was designed to assess this relationship in both male and female subjects over a broader range of ages.

Genome replication, virion secretion, and e antigen expression of naturally occurring hepatitis B virus core promoter mutants.

The core promoter mutants of hepatitis B virus (HBV) emerge as the dominant viral population at the late HBeAg and the anti-HBe stages of HBV infection, with the A1762T/G1764A substitutions as the hotspot mutations. The double core promoter mutations were found by many investigators to moderately enhance viral genome replication and reduce hepatitis B e antigen (HBeAg) expression. A much higher replication capacity was reported for a naturally occurring core promoter mutant implicated in the outbreak of fulminant hepatitis, which was caused by the neighboring C1766T/T1768A mutations instead.

Mammographic findings in pseudoxanthoma elasticum.

Background: There have been isolated case reports of arterial and skin calcification in mammograms of patients with pseudoxanthoma elasticum (PXE), and unpublished anecdotes of many women with PXE undergoing breast biopsy for evaluation of microcalcifications.

Objective: Our aim was to systematically evaluate mammography and breast pathology in PXE.

Methods: The mammograms of 51 women with confirmed PXE were compared with those of a control sample of 109 women without PXE, noting each of the following characteristics on each mammogram: breast density, skin thickening, skin microcalcifications, vascular calcification, breast microcalcifications and macrocalcifications, and masses.

Psychological and fitness changes associated with exercise participation among women with breast cancer.

Exercise participation has been shown to improve cardiovascular fitness and reduce psychological distress among women receiving chemotherapy and/or radiation. The purpose of this pilot study was to examine the changes in distress and body image, and fitness following exercise participation among 24 women who had been diagnosed with breast cancer within the previous 3 years. The women were randomly assigned to participate in a 12-week supervised aerobic exercise program in a hospital setting or a wait-list control group.

Nitric oxide synthase-3 overexpression causes apoptosis and impairs neuronal mitochondrial function: relevance to Alzheimer's-type neurodegeneration.

Dementia in Alzheimer's disease (AD) is correlated with cell loss that is mediated by apoptosis, mitochondrial (Mt) dysfunction, and possibly necrosis. Previous studies demonstrated increased expression of the nitric oxide synthase 3 (NOS3) gene in degenerating neurons of AD brains. For investigating the role of NOS3 overexpression as a mediator of neuronal loss, human PNET2 central nervous system-derived neuronal cells were infected with recombinant adenovirus vectors that expressed either human NOS3 or green fluorescent protein cDNA under the control of a CMV promoter.

Reference values for second trimester fetal and neonatal organ weights and measurements.

To establish accurate reference ranges for the entire second trimester, we documented organ weights, body weight, and linear measurements for 597 fetuses and neonates with gestational ages ranging from 12 to 26 wk. We determined the mean and standard deviation for weights and measurements at each week of gestation using the StatView trade mark SE + Graphics statistical program. The analyses revealed a linear correlation between the gestational age and, respectively, the toe-heel length, crown-rump length, and crown-heel length.

Neuropsychological changes and treatment compliance in older adults with sleep apnea.

Introduction: Apnea is a common disorder in older adults and has been shown to affect cognition. Some studies suggest that treatment for apnea improves certain cognitive deficits, but few studies have examined the relationship between compliance and cognitive improvement. We designed a study to answer the following questions about sleep apnea, cognition and treatment in older adults: (1) Which neuropsychological (NP) variables are differentially associated with measures of sleep fragmentation and oxygen desaturation? (2) Does compliant use of CPAP provide a cognitive advantage over noncompliant use? (3) Does NP performance at baseline predict compliance at 3 months?

Method: Twelve participants were recruited for the study.

Impact of weight-cycling history on bone density in obese women.

Objective: The purpose of this study was to examine the effect of weight cycling (as defined by the frequency and magnitude of intentional weight loss) on bone mineral density and bone mineral content in obese sedentary women.

Research Methods And Procedures: Bone mineral content and density measured by DXA, submaximal physical fitness assessment, nutrient intake, oral contraceptive use, and weight-cycling history were assessed in 195 healthy, overweight sedentary women (age, 21 to 45 years; body mass index, 27 to 40 kg/m(2)) before beginning a behavioral weight-loss intervention.

Results: After controlling for body weight, multivitamin use, oral contraceptive/estrogen use, and calcium and magnesium intake, women who had a history of weight cycling did not have significantly lower total-body bone mineral content or density or total femur bone mineral density.

Triplet placentas: reference values for weights.

The occurrence of twins, triplets, and other multiple births increased significantly between 1970 and 2000 in the United States and other industrialized countries. The number of triplet placentas submitted for examination as pathologic specimens has also markedly increased, but no reference values are published for triplet weights. We examined 196 normal triplet placentas.

Reference values for transverse cerebellar diameter throughout gestation.

The transverse cerebellar diameter (TCD) is well established in the ultrasound literature as a reliable parameter for estimating the duration of gestation. In cases of growth restriction the cerebellum is usually spared, making TCD a reliable indicator of gestational age even when other parameters fall off the appropriate growth curve. The purpose of this study is to establish normal values for the transverse diameter of the cerebellum in pathology specimens, and to determine if these values correlate with those obtained by ultrasound.

Multicenter trial of fluoxetine as an adjunct to behavioral smoking cessation treatment.

The authors evaluated the efficacy of fluoxetine hydrochloride (Prozac; Eli Lilly and Company, Indianapolis, IN) as an adjunct to behavioral treatment for smoking cessation. Sixteen sites randomized 989 smokers to 3 dose conditions: 10 weeks of placebo, 30 mg, or 60 mg fluoxetine per day. Smokers received 9 sessions of individualized cognitive-behavioral therapy, and biologically verified 7-day self-reported abstinence follow-ups were conducted at 1, 3, and 6 months posttreatment.

Failure of macrolide antibiotic treatment in patients with bacteremia due to erythromycin-resistant Streptococcus pneumoniae.

The rate of macrolide resistance among Streptococcus pneumoniae is increasing, but some investigators have questioned its clinical relevance. We conducted a matched case-control study of patients with bacteremic pneumococcal infection at 4 hospitals to determine whether development of breakthrough bacteremia during macrolide treatment was related to macrolide susceptibility of the pneumococcal isolate. Case patients (n=86) were patients who had pneumococcal bacteremia and an isolate that was either resistant or intermediately resistant to erythromycin.

Cardiopulmonary resuscitation using the cardio vent device in a resuscitation model.

To compare the "Bellows on Sternum Resuscitation" (BSR) device that permits simultaneous compression and ventilation by one rescuer with two person cardiopulmonary resuscitation (CPR) with bag-valve-mask (BVM) ventilation in a single blind crossover study performed in the laboratory setting. Tidal volume and compression depth were recorded continuously during 12-min CPR sessions with the BSR device and two person CPR. Six CPR instructors performed a total of 1,894 ventilations and 10,532 compressions in 3 separate 12-min sessions.

Pulmonary function characteristics in patients with different patterns of methacholine airway hyperresponsiveness.

Study Objectives: The American Thoracic Society guidelines for methacholine-induced airway hyperresponsiveness include a > or = 20% reduction in FEV(1) or a > or = 40% reduction in specific airway conductance (sGaw). The objectives of the current study are to assess the concordance between these two criteria and to characterize the pulmonary function and respiratory symptoms of patients with different patterns of methacholine hyperresponsiveness.

Study Design: A prospective study of 248 consecutive patients referred for methacholine bronchoprovocation testing.

Cognitive and behavioral features discriminate between Alzheimer's and Parkinson's disease.

Objective: To compare the cognitive and behavioral profiles of Alzheimer's disease (AD) and cognitively impaired patients with Parkinson's disease (PD) and to determine the individual measures that best discriminate the two patient groups.

Background: Neuropsychologic studies of patients with AD and PD have generated debate over the distinction between "cortical" and "subcortical" dementias, with some studies showing significant differences and others showing little difference in the cognitive profiles of these groups. Studies evaluating behavioral differences between the patient groups have been somewhat more successful in adequately discriminating these syndromes.

Laparoscopic gastrostomy in infants and children.

Gastrostomy is a common procedure in children. Percutaneous endoscopic gastrostomy (PEG) is less traumatic than open surgery, but carries a higher risk in small children. We report our experience with laparoscopic gastrostomy, which appears to combine the advantages of the PEG and the safety of an open operation.

The effects of the introduction of a high-nutrient transitional formula on growth and development of very-low-birth-weight infants.

Objective: The purpose of this study was to determine the impact of introducing a high-nutrient transitional formula (TF) for use after discharge on the growth and development of premature infants.

Study Design And Methods: This was a cohort study of all surviving infants with a birth weight < or =1250 g admitted to the neonatal intensive care unit between January 1, 1995 and December 31, 1996. Infants with major congenital abnormalities were excluded.

Cyclic mechanical stretch inhibits cell proliferation and induces apoptosis in fetal rat lung fibroblasts.

Development of the pulmonary air sacs is crucial for extrauterine survival. Late fetal lung development is characterized by a thinning of the mesenchyme, which brings pneumocytes and endothelial cells into apposition. We hypothesized that mechanical stretch, simulating fetal breathing movements, plays an important role in this remodeling process.

HIF-1 expression in healing wounds: HIF-1alpha induction in primary inflammatory cells by TNF-alpha.

The expression of the hypoxia-responsive transcription factor hypoxia-inducible factor (HIF)-1 during acute inflammation was investigated in experimental wounds. HIF-1alpha mRNA was maximally expressed in wound cells 6 h after injury. HIF-1alpha protein was detectable in wound cells 1 and 5 days after injury.

A prospective case-control study of the role of astrovirus in acute diarrhea among hospitalized young children.

This study examines the importance of astroviruses as a cause of acute diarrhea in hospitalized children <10 years old during a 5-year period. Stools were screened by electron microscopy and were tested for astrovirus, rotavirus, and enteric adenovirus by EIA. During the study, 14.

A beta-blocker, not magnesium, is effective prophylaxis for atrial tachyarrhythmias after coronary artery bypass graft surgery.

Objective: To evaluate magnesium as a sole or adjuvant agent with currently used prophylactic drugs in suppressing postoperative atrial tachyarrhythmias (POAT) after coronary artery bypass graft (CABG) surgery.

Design: Single-center prospective, randomized clinical trial.

Setting: University hospital.

Physician-based activity counseling: intervention effects on mediators of motivational readiness for physical activity.

In theory-based interventions for behavior change, there is a need to examine the effects of interventions on the underlying theoretical constructs and the mediating role of such constructs. These two questions are addressed in the Physically Active for Life study, a randomized trial of physician-based exercise counseling for older adults. Three hundred fifty-five patients participated (intervention n = 181, control n = 174; mean age = 65.

Ca2+-induced contraction of cat esophageal circular smooth muscle cells.

ACh-induced contraction of esophageal circular muscle (ESO) depends on Ca2+ influx and activation of protein kinase Cepsilon (PKCepsilon). PKCepsilon, however, is known to be Ca2+ independent. To determine where Ca2+ is needed in this PKCepsilon-mediated contractile pathway, we examined successive steps in Ca2+-induced contraction of ESO muscle cells permeabilized by saponin.