Leptin regulates CD16 expression on human monocytes in a sex-specific manner.

Fat mass is linked mechanistically to the cardiovascular system through leptin, a 16 kDa protein produced primarily by adipocytes. In addition to increasing blood pressure via hypothalamic-sympathetic pathways, leptin stimulates monocyte migration, cytokine secretion, and other functions that contribute to atherosclerotic plaque development. These functions are also characteristics of CD16-positive monocytes that have been implicated in the clinical progression of atherosclerosis. This investigation sought to determine if leptin promoted the development of such CD16-positive monocytes. Cells from 45 healthy men and women with age ranging from 20 to 59 years were analyzed. Circulating numbers of CD14(++)16(++) monocytes, which are primary producers of TNFα, were positively related to plasma leptin concentrations (P < 0.0001), with a stronger correlation in men (P < 0.05 for leptin × sex interaction). In vitro, recombinant human leptin induced CD16 expression in a dose-related manner (P = 0.02), with a stronger influence on monocytes from men (P = 0.03 for leptin × sex interaction). There were no sex-related differences in total leptin receptor expression on any monocyte subtypes, relative expression of long versus short isoforms of the receptor, or soluble leptin receptor concentrations in the plasma. The number of circulating CD14(+)16(++) monocytes, which preferentially migrate into nascent plaques, was positively related to systolic blood pressure (R = 0.56, P = 0.0008) and intima-media thickness (R = 0.37, P = 0.03), and negatively related to carotid compliance (R = -0.39, P = 0.02). These observations indicate that leptin promotes the development of CD16-positive monocyte populations in a sex-specific manner and that these subpopulations are associated with diminished vascular function.

Tobacco prevention in children and cessation in family members.

PURPOSE: To examine the effects of a theory-driven tobacco prevention program in sixth-grade children with a family tobacco cessation component implemented by school nurses in conjunction with the initiation of a statewide toll-free Quit Line. DATA SOURCES: Self-report questionnaires completed by the sixth-grade children and their parents/guardians (N= 1024) representing largely rural southern school systems from disparate areas with high prevalence rates of tobacco use and lung cancer diagnoses. Pre- and posttest measures that evaluated the impact of both student and parent/guardian interventions were obtained over a 10-week period. Paired t-tests were used to examine differences between pre- and posttest scores for all student and parent/guardian variables. Repeated-measures analysis of variance was used to examine the effect of parent/guardian smoking on student pre- and posttest scores. CONCLUSIONS: The student program resulted in significant improvements in drug knowledge, refusal skills, attitudes, normative expectations, assertiveness, and anxiety reduction techniques. In addition, the effectiveness of several components of the tobacco prevention program for the children was impacted by the smoking status of their parents/guardians. Drug-use intentions and behaviors were lower at posttest for children from homes of nonsmokers versus children from homes of smokers. Parents/guardians consistently reported that smoking was detrimental to themselves, the public, and their children. Of those parents/guardians who identified themselves as smokers (26%) and received cessation materials, 46.4% indicated that the information motivated them to want to quit. IMPLICATIONS FOR PRACTICE: Tobacco use continues to be the leading cause of preventable death in the United States, with greater than 2000 new youth becoming regular smokers each day. School nurses and nurse practitioners are in various pivotal positions to address tobacco and its related health concerns through delivery of effective family interventions that target children for tobacco prevention and parent/guardian smokers for cessation.

School-based asthma: a study in an African American elementary school.

ISSUES AND PURPOSE: Chronic illnesses, such as asthma experienced by children, are difficult for families and school professionals to manage. This study explored beliefs about asthma and asthma management among schoolchildren, parents, and teachers in an African American school. DESIGN AND METHODS: Focus groups were conducted with schoolchildren, parents, and teachers. Data were analyzed by content analysis; segments of information were categorized into groups that were later abstracted into themes illustrating beliefs and behaviors about asthma. RESULTS: The children reported fear of not being able to breathe and the limitations of living with asthma. The teachers were concerned that they did not have a sufficient understanding of asthma to manage children's asthma during the school day. Parents described complex lifestyles and the challenges of asthma management.