A Separate Role for ICAM‐1 and Fluid Shear in Regulating Leukocyte Interactions with Straight Regions of Venular Wall and Venular Convergences

Objective: Variation in expression of adhesion molecules plays a key role in regulating leukocyte behavior, but the contribution of fluid shear to these interactions cannot be ignored. Here, we dissected the effects of each of these factors on leukocyte behavior in different venular regions. Materials and Methods: Leukocyte behavior was quantified in blood‐perfused microvascular networks in anesthetized mouse cremaster muscle, using intravital confocal microscopy. ICAM‐1 expression and fluid shear rate were quantified by using ICAM‐1 fluorescent labeling, fluorescent particle tracking, and computational fluid dynamics. Results: Tumor necrosis factor alpha induced an increase in ICAM‐1 expression and abolished the differences observed among control venules of different sizes. Consequently, leukocyte adhesion was increased to a similar level across all vessel sizes [5.1±0.46 leukocytes/100 μm vs. 2.1±0.47 (control)], but remained significantly higher in venular convergences (7.8±0.4). Leukocyte transmigration occurred primarily in the smallest venules and venular convergences (23.9±5.1 and 31.9±2.7 leukocytes/10,000 μm² tissue, respectively). In venular convergences, the two inlet vessels are predicted to create a region of low velocity, increasing leukocyte adhesion probability. Conclusions: In straight regions of different‐sized venules, the variability in ICAM‐1 expression accounts for the differences in leukocyte behavior; in converging regions, fluid shear potentially has a greater effect on leukocyte endothelial cell interactions.     

CELLULAR IMMUNITY AND CHLAMYDIA GENITAL INFECTION: INDUCTION,RECRUITMENT, AND EFFECTOR MECHANISMS

Chlamydia trachomatis is one of the major causes of bacterial sexually transmitted disease worldwide. The initial infection of endocervical epithelium in females is asymptomatic and commonly ascends to fallopian tubes when left untreated. Immunity to Chlamydia develops after infection and appears to provide short-term protection. Consequently, a significant rate of reinfection occurs among sexually active individuals, which can result in reproductive disability. T helper type 1 responses are implicated in providing protective immunity but may also contribute to tubal infertility. The purpose of this chapter is to review the factors that regulate the induction and recruitment of protective cellular immune responses within the local genital mucosa. An understanding of these events is important for the design of a protective vaccine and control of immunopathologic reactions.     

Maternal Acceptability of a Dietary Intervention Designed to Lower Children''s Intake of Saturated Fat and Cholesterol: The Dietary Intervention Study in Children (DISC)

Objective This report examined the acceptability to mothers of a dietary educational and behavioral intervention for preadolescent children with elevated levels of serum low-density lipoprotein cholesterol (LDL-C) who were enrolled in the Dietary Intervention Study in Children (DISC).Design DISC is a randomized, controlled clinical trial. Subjects were randomly assigned to either an intervention or usual-care (control) group.Subjects/setting To be eligible for the study, participants were required to have the average of 2 fasting LDL-C values fall between the 80th and 98th sex-specific percentiles. Three hundred thirty-four 8- to 10-year-old children and their families were randomly assigned to an intervention group, and 329 were assigned to a usual-care (control) group. This study examined data from 232 subjects in the intervention group. Data were collected at 6 intervention sites around the United States.Intervention Those assigned to the intervention group participated in a multidisciplinary dietary intervention that included a series of group and individual sessions over a 3-year period. Children and their caretakers were taught to follow a nutritionally adequate diet that was low in total fat, saturated fat, and cholesterol and high in polyunsaturated fat.Main outcome measures Three nonconsecutive 24-hour diet recalls were collected at baseline and at 1 year by trained and certified dietitians. A questionnaire designed to assess diet acceptability was administered at months 4, 8, 11, and 15. Demographic measures were collected at the onset of the study.Statistical analysis performed Statistical procedures included factor analysis and regression analysis.Results Regression analysis suggested that perceived effectiveness of the dietary intervention and mothers’ having few concerns about disadvantages of the diet were significantly related to higher overall fat intake in children in one-parent families. Maternal willingness to implement the diet was significantly related to lower saturated fat intake.Applications/conclusions In attempts to change eating behavior of children, interest and cooperation of the parents are essential to achieving successful results. These analyses further suggest that maternal acceptability translates into willingness to implement the diet and may facilitate changes that are associated with reduced saturated fat intake in children. J Am Diet Assoc. 1998;98:31-34.     

Noradrenaline release and clearance in relation to age and blood pressure in man

Abstract. Plasma noradrenaline concentration increases with age. This study was designed to investigate whether an increased rate of noradrenaline release into the circulation or a decrease in clearance is primarily responsible for this age related change in concentration. Sixteen healthy male subjects were studied, eight young (21–36 years) and eight old (65–78 years). Clearance was calculated from steady state noradrenaline concentrations during constant rate infusions of unlabelled noradrenaline. Clearance did not differ between the two groups: young 4.8 1/min (range 2.7–6.1), old 4.1 (range 2.6–8.2). The old subjects had significantly greater rates of release. Supine: young 10.3 nmol/min (range 5.3–17.6), old 19.7 (range 10.1–30), P <0.05. Standing: young 17.2 (range 11–36.4), old 29.2 (range 21.8–47.9), P <0.01. No significant relationship was found in either supine or standing position between rate of noradrenaline release and either systolic or diastolic blood pressure. These results indicate that plasma noradrenaline concentration rises with age because of an increased rate of release, but that this increased release is not responsible for the higher blood pressure seen in the elderly.     

The Role of the Nurse During Amniocentesis

Amniocentesis is a relatively simple, safe, and accurate diagnostic tool which is being performed with increased frequency in local hospitals. The maternity nurse has a responsibility to know the clinical applications, the role of the nurse during the procedure, and the potential risks associated with amniocentesis.