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Biomedical subjects

B J Zimmerman

Publications and source records attributed to B J Zimmerman.

At least 19 recordsLinked to original sources

Self-regulation training enhances dietary self-efficacy and dietary fiber consumption.

OBJECTIVE: To evaluate the effectiveness of incorporating two self-regulation strategies (goal setting and self-monitoring) into a nutrition education class to enhance dietary fiber self-efficacy and foster a positive change in dietary fiber consumption. DESIGN: College students in an introductory nutrition class (n = 113) were randomly assigned to one of four treatment conditions: goal setting, self-monitoring, goal setting and self-monitoring, and no goal setting and no self-monitoring. Twenty-six college students from an introductory health class served as the control group. STATISTICAL ANALYSES: The main and interaction effects of goal setting and self-monitoring on postintervention variables were analyzed using analysis of covariance with baseline intake levels as the covariate. Analysis of variance was used to examine differences in the mean changes between the groups. Path analysis was conducted to analyze the causal linkage among the pretest and intervening variables to predict postintervention knowledge, self-efficacy, and fiber consumption. RESULTS: Goal setting had a significant main effect on dietary fiber self-efficacy and on dietary fiber consumption Subjects who set goals scored 15% higher on the dietary fiber self-efficacy scale and consumed 91% more fiber than subjects who did not set goals. Self-monitoring had no significant main effect on either dietary fiber self-efficacy or dietary fiber consumption. There was no significant interaction between goal setting and self-monitoring. Changes in dietary fiber scores differed between the groups. Increases in dietary fiber for the goal setting and self-monitoring group were significantly higher than the goal-setting, self-monitoring, no goal setting and no self-monitoring, and control groups. In addition, the goal setting only group had significantly greater increases in fiber intake than the self-monitoring, no goal setting and no self-monitoring, and control groups. Changes in self-efficacy scores were significantly different between the groups. The goal setting and goal setting and self-monitoring groups had significantly higher self-efficacy scores than the control group. Path analysis revealed that both goal setting and self-monitoring affected dietary fiber consumption through knowledge and dietary fiber self-efficacy, goal setting had a strong direct effect on fiber consumption, and postintervention knowledge affected fiber consumption only through self-efficacy. APPLICATIONS/CONCLUSIONS: Our findings suggest that dietary change requires active self-regulation of food intake. Combining goal setting and self-monitoring significantly enhances dietary behavior change. This strategy can easily be incorporated into nutrition education or counseling programs to enhance dietary behavior change.

Adolescent↗

Self-efficacy, activity participation, and physical fitness of asthmatic and nonasthmatic adolescent girls.

The prevalence of asthma, lung self-efficacy beliefs, physical activities, and physical fitness of adolescent girls were studied in a private inner-city high school serving a multiethnic, middle-class population using a questionnaire, a test of physical fitness, and an activity log. Twenty-two percent of the 172 girls were diagnosed with asthma, and an additional 15% of the girls experienced breathing difficulties. It was found that asthmatic girls were less physically fit, reported lower self-efficacy regarding their lung functioning during vigorous activities, and participated less often in those activities than nonasthmatic girls. Perceived lung efficacy was found to predict girls' subsequent participation in physical activities significantly, even when the effects of asthma, smoking, and physical fitness were controlled statistically.

Adolescent↗

Comparison of three types of postoperative management for endoscopic plantar fasciotomy. A retrospective study.

This study compared three types of postoperative management of patients undergoing endoscopic plantar fasciotomy. Participating in the study were 38 patients (45 feet) who had undergone endoscopic plantar fasciotomy from 1995 to 1998. One group of patients wore a below-the-knee walking cast with a molded medial longitudinal arch for 2 weeks; another group was allowed immediate plantigrade weightbearing; the third group was nonweightbearing with crutch-assisted ambulation for 2 weeks. The results showed that the patients who wore the below-the-knee walking cast for 2 weeks required less time to obtain 80% pain relief, needed less time to return to full activities, and had fewer complications than those patients who were allowed immediate plantigrade weightbearing. Moreover, patients who wore the below-the-knee walking cast were more satisfied with their postoperative results than patients who were nonweightbearing for 2 weeks.

Adult↗

Polyamine depletion arrests cell cycle and induces inhibitors p21(Waf1/Cip1), p27(Kip1), and p53 in IEC-6 cells.

The polyamines spermidine and spermine and their precursor putrescine are intimately involved in and are required for cell growth and proliferation. This study examines the mechanism by which polyamines modulate cell growth, cell cycle progression, and signal transduction cascades. IEC-6 cells were grown in the presence or absence of DL-alpha-difluoromethylornithine (DFMO), a specific inhibitor of ornithine decarboxylase, which is the first rate-limiting enzyme for polyamine synthesis. Depletion of polyamines inhibited growth and arrested cells in the G1 phase of the cell cycle. Cell cycle arrest was accompanied by an increase in the level of p53 protein and other cell cycle inhibitors, including p21(Waf1/Cip1) and p27(Kip1). Induction of cell cycle inhibitors and p53 did not induce apoptosis in IEC-6 cells, unlike many other cell lines. Although polyamine depletion decreased the expression of extracellular signal-regulated kinase (ERK)-2 protein, a sustained increase in ERK-2 isoform activity was observed. The ERK-1 protein level did not change, but ERK-1 activity was increased in polyamine-depleted cells. In addition, polyamine depletion induced the stress-activated protein kinase/c-Jun NH2-terminal kinase (JNK) type of mitogen-activated protein kinase (MAPK). Activation of JNK-1 was the earliest event; within 5 h after DFMO treatment, JNK activity was increased by 150%. The above results indicate that polyamine depletion causes cell cycle arrest and upregulates cell cycle inhibitors and suggest that MAPK and JNK may be involved in the regulation of the activity of these molecules.

Animals↗

Self-regulating childhood asthma: a developmental model of family change.

This article tests a model of self-regulatory development in which families' cognitive beliefs and behavioral skills for managing asthma symptoms emerge in four successive phases: asthma symptom avoidance, asthma acceptance, asthma compliance, and asthma self-regulation. Confirmatory factor analyses revealed that the hypothesized multiphase model provided the best factorial fit for phase items. Subsequent Guttman analyses of the families' phase scores revealed a high degree of sequential ordering. Finally, trend analyses of family phase differences revealed a significant negative linear relation with measures of asthma severity and a significant positive linear relation with physician care and concern measures, asthma regulatory measures, and beliefs in Western biomedical practices. Despite receiving primary care for asthma at a major metropolitan university hospital, 83% of the sample were classified as precompliant. The phase model of asthma self-regulatory development offers a qualitative approach for investigating the psychological determinants of asthma self-regulatory behavior.

Adaptation, Psychological↗

Polyamine deficiency alters EGF receptor distribution and signaling effectiveness in IEC-6 cells.

Cell growth and migration are essential processes for the differentiation, maintenance, and repair of the intestinal epithelium. Epidermal growth factor (EGF) is an important factor in the reorganization of the cytoskeleton required for both processes. Because we had previously found significant changes in the cytoskeleton during polyamine deficiency, it was of interest to know whether those changes could prevent EGF from stimulating growth and migration. Polyamine biosynthesis in IEC-6 cells was interrupted by treatment with alpha-difluoromethylornithine (DFMO), a specific inhibitor of ornithine decarboxylase, the primary rate-limiting enzyme of polyamine biosynthesis. DFMO halted cell proliferation and inhibited cell migration, and neither function could be normally stimulated by EGF. Immunocytochemistry of the transferrin receptor (used as a marker for the endocytic pathway) revealed an abnormal distribution of the EGF receptor (EGFR) 10 min after binding EGF. Polyamine deficiency depleted the cells of interior microfilaments, thickened the actin cortex, and prevented the prompt association of EGF-bound EGFR with actin. EGF-stimulated 170-kDa protein tyrosine phosphorylation and the kinase activity of purified membrane EGFR were reduced by 50%. Immunoprecipated EGFR protein concentration, however, was not reduced by polyamine deficiency. All of these changes could be prevented by supplementation with putrescine. Cytoskeletal disruption, reduced EGFR phosphorylation and kinase activity, aberrant intracellular EGFR distribution, and delayed association with actin filaments suggest a partial explanation for the dependence of epithelial cell growth and migration on polyamines.

Animals↗

A study of role ambiguity and role strain among school nurses.

Two hundred fifty-one school nurses practicing in pennsylvania were surveyed regarding perceptions of their professional role. Findings demonstrated that role ambiguity and role strain occur when school nurses attempt to practice in a setting where two disciplines, education and nursing, may have different expectations regarding role performance.

Adult↗

Self-efficacy expectations among traumatized adolescents.

Bandura's Multidimensional Scales of Perceived Self-Efficacy (MSPSE) were administered to three matched groups of adolescents. The first group met diagnostic criteria for PTSD. The second had been exposed to qualitatively and quantitatively similar stressors and did not meet criteria for PTSD (traumatized PTSD negatives). The third group consisted of non-traumatized controls. Data analysis revealed that the adolescents with PTSD had appreciably lower self-efficacy ratings on eight of the nine subtests that comprise the MSPSE. Non-significant differences were observed when the MSPSE subtest scores of the traumatized PTSD negatives and controls were compared.

Adaptation, Psychological↗

Structural requirements of analogues of polyamines for migration and growth of IEC-6 cells.

Healing of gastrointestinal mucosal lesions occurs through two processes: an early one involving cell migration and a later one in which cell division replaces lost cells. Both processes require the presence of polyamines, but the mechanism of action of these compounds is unknown. In the present study, we examined the ability of analogues of spermidine and spermine to support migration and growth of IEC-6 cells that have been grown in alpha-difluoromethylornithine to inhibit polyamines. All analogues of spermidine with the general formula x-3 (referring to the numbers of carbon atoms on either side of the central nitrogen), where x = 2-12, competed with spermidine for entry into the cells. However, in addition to spermidine (x = 4), only compounds for which x = 2, 3, or 6 supported migration and only those for which x = 2 or 7 supported growth. Spermine analogues 3-x-3, for which x = 3, 6, 9, or 12, competed for entry into the cells, but only compounds for which x = 3 or 6 supported migration and only the compound for which x = 3, in addition to spermine (x = 4), supported growth. In addition, analogues 2-3-2, 3-2-3, and 2-(3)2, a branched compound, supported both migration and growth but entered the cell via a mechanism different than that for spermidine and spermine. These data define some of the specific structural requirements for polyamines to produce their physiological effects.

Animals↗

Mechanisms of reperfusion injury.

Reperfusion of ischemic organs can result in tissue injury that is manifested as microvascular and parenchymal cell dysfunction. Reactive oxygen metabolites and polymorphonuclear leukocytes (PMN) have been implicated in the pathobiology of reperfusion injury. Reactive oxygen metabolites mediate the lipid peroxidation detected in postischemic tissues and promote the formation of inflammatory agents that recruit and activate PMN. These PMN appear to inflict reperfusion-induced tissue injury. Drugs that scavenge or inhibit the formation of reactive oxygen metabolites and/or prevent the recruitment of PMN may be useful in the treatment of reperfusion injury.

Animals↗

Molecular determinants of lipid mediator-induced leukocyte adherence and emigration in rat mesenteric venules.

The objective of this study was to identify the molecular determinants of leukocyte rolling, adherence, and emigration elicited in postcapillary venules by the lipid mediators leukotriene B4 (LTB4) or platelet-activating factor (PAF). Leukocyte-endothelial cell adhesion and shear rate were monitored in rat mesenteric venules during superfusion with either LTB4 or PAF in the presence or absence of monoclonal antibodies (MAbs) directed against either leukocyte (CD18, CD11b) or endothelial cell [intercellular adhesion molecule 1 (ICAM-1), E-selectin, P-selectin] adhesion glycoproteins. In untreated animals and in animals receiving a nonbinding control MAb, LTB4 and PAF increased the number of both adherent (8- and 4-fold, respectively) and emigrated (14- and 8-fold, respectively) leukocytes, while reducing leukocyte rolling velocity (36 and 33%, respectively). The LTB4- and PAF-induced leukocyte adherence and emigration were significantly attenuated by pretreatment with MAbs directed against CD18, CD11b, ICAM-1, and E-selectin, but not P-selectin. The reduction in leukocyte rolling velocity induced by LTB4 was not affected by any of the MAbs; however, both P- and E-selectin MAbs significantly attenuated the reduction in leukocyte rolling velocity elicited by PAF. The results of this study indicate that the leukocyte adherence and emigration induced by both LTB4 and PAF are mediated by CD11b/CD18 on leukocytes and by ICAM-1 and E-selectin on endothelial cells. The molecular determinant of leukocyte rolling appears to be mediator specific, with the selectins mediating the rolling elicited by PAF.

Animals↗

Thrombin receptor peptide-mediated leukocyte rolling in rat mesenteric venules: roles of P-selectin and sialyl Lewis X.

Neutrophil adhesion to monolayers of cultured endothelial cells is enhanced, via a P-selectin-mediated mechanism, by a 14-amino acid peptide fragment (TRP-14) of the thrombin receptor. The objective of this study was to determine whether TRP-14 promotes P-selectin-mediated sialyl Lewis X-dependent leukocyte rolling in postcapillary venules. Superfusion of the rat mesentery with TRP-14 for 30 min resulted in the recruitment of rolling leukocytes and a concomitant reduction in leukocyte rolling velocity. Analogues of TRP-14 were largely ineffective in promoting leukocyte-endothelial cell adhesion. Treatment with either a monoclonal antibody directed against rat P-selectin or soluble sialyl Lewis X oligosaccharide (the carbohydrate ligand to P-selectin found on leukocytes) significantly attenuated the TRP-14-induced recruitment of rolling leukocytes. However, no effect was observed with a nonbinding antibody or a control fucose-deficient oligosaccharide. These results indicate that TRP-14 elicits the recruitment of rolling leukocytes in postcapillary venules via a P-selectin-dependent mechanism. The results also support the view that sialyl Lewis X participates in P-selectin-mediated leukocyte-endothelial cell adhesion.

Animals↗

Patient and family management of asthma: theory-based techniques for the clinician.

Several model asthma education programs are available to improve patient self-management, and elements of these models are discussed as they relate to the teaching role of health-care providers. Self-regulation is being explored in current asthma education research, and preliminary findings of a study are presented that show self-regulation behaviors to be associated with more frequent use of asthma management strategies by patients. Using more management strategies was associated with being observant of symptoms (p = .0001) and feeling confident to manage them (p = .01). Taking more preventive actions was associated with being observant (p = .001) and feeling confident to keep the child out of the triggering situation (p = .02) and prevent symptoms (p = .001). Important issues arising from recent psychosocial research are outlined for consideration by the clinician. These include ways that counseling by the health professional can encourage self-regulation and better at-home management of asthma.

Adult↗