Retention of African-American students in baccalaureate nursing programs: are we doing enough?

With the increasing minority population in the United States, much attention has been given to the lack of diversity among health care professionals, specifically nursing. Since the 1960s, the federal government has provided financial resources to institutions of higher education whose purpose was to diversify the health care profession. Historically, these resources have supported initiatives that primarily focused on the recruitment of minority students into higher education. These efforts temporarily increased the enrollment of students from varying racial and ethnic backgrounds. However, without established retention initiatives in place, the attrition rates for students from diverse backgrounds far exceeded the enrollment rates. Consequently, the nursing workforce continues to be a predominantly White female profession. In order for schools of nursing to create a workforce reflective of its patient population, both nursing education and institutions of higher education must be committed to implementing initiatives to increase the retention and graduation rates of minority students.     

Serum Troponin I and Myoglobin After Monophasic versus Biphasic Transthoracic Shocks for Cardioversion of Persistent Atrial Fibrillation

This study compared the effects of standard monophasic versus biphasic direct current shocks for cardioversion of atrial fibrillation (AF) on the release of cardiac troponin I (cTnI) and myoglobin (Myo). We randomized 48 patients with persistent AF (mean age = 61.4 ± 10.7 years, 33 men) to monophasic (45.2%) or biphasic (54.8%) cardioversion. Plasma concentrations of cTn1 and Myo were measured before, and 6 and 24 hours after the procedure. Cardioversion was significantly more effective (88% vs 100%, P < 0.04) and required less energy (348.1 ± 254.1 vs 187.6 ± 105.3 J; P < 0.001) in the biphasic than the monophasic group. A significant increase in mean plasma cTnI concentration over 24 hours (0.23 ± 0.18 vs 0.41 ± 0.37 ng/mL, P < 0.04), and mean Myo concentration were recorded in the monophasic group over the first 6 hours following the procedure (38.2 ± 14.2 vs 221.9 ± 51.3 ng/mL, P < 0.001), whereas no significant increase was observed in the biphasic group. Increases in cTnI and Myo in the monophasic group correlated closely with the cumulative energy delivered (Spearman correlation coefficient r = 0.58, P = 0.004 for Myo and r = 0.67, P < 0.001 for cTnI). In addition, there was a positive correlation between cumulative cardioversion energy load and increase in Myo and cTnI indexed with left ventricular mass (r = 0.45, P < 0.02 for Myo and r = 0.47, P = 0.01 for cTnI). It is concluded that in cardioversion of AF, biphasic are more effective than monophasic and may cause less myocardial injury.     

Hemostatic enzyme generation in the blood of patients with hereditary protein C deficiency

The presence of hereditary protein C deficiency has been shown to predispose patients to the development of venous thrombosis. We used radioimmunoassays for the protein C activation peptide (PCP) and the prothrombin fragment F1 + 2 to quantitate the extent of in vivo activation of protein C by thrombin-thrombomodulin and prothrombin by factor Xa, respectively, in the blood of individuals with this clinical disorder. A total of 46 protein C deficient subjects from 18 kindreds were studied. In 23 nonanticoagulated patients with an isolated deficiency of protein C, the mean level of PCP was substantially reduced while the mean concentration of F1 + 2 was significantly elevated as compared with normal controls (1.10 pmol/L v 1.78 pmol/L, P less than .0005 and 2.54 nmol/L v 1.51 nmol/L, P less than .0005, respectively). The metabolic behavior of 131I-F1 + 2 was found to be similar in protein C deficient patients and normal individuals. However, we were unable to establish a significant correlation between decreased PCP levels and increased F1 + 2 measurements in these 23 patients. This study demonstrates that heterozygous protein C deficient individuals with equivalent plasma levels of the zymogen may have markedly different biochemical profiles when assay techniques are used that quantitate the in vivo activity of the coagulation system. Six individuals from three pedigrees were identified as having combined deficiencies of protein C and either antithrombin III or protein S; the genetic basis for the combined deficiency state was determined in two of the kindreds. Finally we observed that hemostatic system activity as measured by the PCP and F1 + 2 assays is markedly suppressed in protein C deficient patients who are chronically anticoagulated with coumarin derivatives.     

Differential activation of leukotriene biosynthesis by granulocyte- macrophage colony-stimulating factor and interleukin-5 in an eosinophilic substrain of HL-60 cells

Cytokines can stimulate eosinophils to produce cysteinyl leukotrienes (LTs) in the lung that provoke tissue destruction associated with asthma. Priming of an eosinophilic substrain of HL-60 cells (HL-60#7) with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) before ionophore challenge was found to produce an apparent 45% increase in total LT production in a dose-dependent manner (ED50 = 150 pmol/L) that could be accounted for by a decrease in the time required for maximal formation of LTs. GM-CSF had no effect on the kinetic parameters of LTC4 synthase and therefore probably acts upstream of this catalytic event. Incubation with interleukin-5 (IL-5), however, had no effect on LT biosynthesis. This differential priming ability was not a consequence of different receptor populations or differences in the affinity or stability of the ligand-receptor complexes of GM-CSF and IL-5. GM-CSF and IL-5 each displayed similar populations of high-affinity binding sites and neither GM-CSF nor IL-5 were able to cross-compete for the other's receptor binding sites. Analysis of phosphotyrosine patterns suggest that IL-5 is incapable of transducing a signal in eosinophilic HL-60#7 cells even though IL-5 and GM-CSF receptors mediate signal transduction via a common beta-chain component that is also necessary for high-affinity binding. Overall, this unique system may permit the dissection of distinct events responsible for specific intracellular signals transduced separately by GM-CSF or IL-5.     

Persistent lymphocytopenia as a diagnostic feature of bronchogenic carcinoma

Patients with abnormalities due to bronchogenic carcinoma, noted on chest films, have decreased peripheral blood lymphocytes and increased total white cells compared to patients with benign lesions. Precision studies of 40 patients revealed that a low percentage of lymphocytes averaged over a three-week period distinguished bronchogenic carcinoma patients from patients with benign lesions with 95 percent overall accuracy. Lesions as small as 1.0 cm were correctly predicted to be malignant. Mean 8 AM plasma cortisol levels were elevated in patients with bronchogenic carcinoma and there was a negative correlation of 8 AM plasma cortisol levels with precentage of lymphocytes. Increased levels of endogenous cortisol may account for lymphocytopenia in bronchogenic carcinoma patients.     

The effect of dexamethasone on the control of plasma aldosterone concentration in normal recumbent man.

In order to evaluate the control of the circadian rhythm of plasma aldosterone concentration in man, plasma aldosterone, cortisol, sodium and potassium concentrations, and plasma renin activity (PRA) were measured in samples obtained at 20-minute intervals from 0200 to 0800 in sodium repleted (180 mEq. per day of diet) and sodium depleted (22 mEq. per day of diet) normal subjects. During sodium replete studies, plasma aldosterone and cortisol concentrations were significantly correlated (p greater than 0.01) in all 4 subjects. Plasma aldosterone also correlated with PRA (p greather than 0.01) in 2 subjects and with potassium (p greater than 0.01) in one. Episodic increases in plasma aldosterone concentration were observed despite suppression of ACTH by dexamethasone treatment. Plasma aldosterone concentrations were significantly correlated with PRA (p greater than 0.05 and p greater than 0.01) in only 2 of 4 subjects under these conditions. Following sodium restriction, plasma aldosterone concentrations were not significantly correlated with plasma cortisol and only infrequently with either PRA or potassium. When dexamethasone was administered during the low sodium diet, correlations with PRA (p greater than 0.001) were seen in 2 of 3 subjects and with potassium (p greater than 0.01) in 1 of 3 subjects. There was no significant correlation between plasma aldosterone and sodium concentration during any of the studies. These results are compatible with the concept that the relative importance of PRA, ACTH, and potassium in inducing changes in aldosterone production during the early morning hours is partially dependent upon dietary sodium, but also varies between individuals studied during similar sodium diets. The episodic alterations of plasma aldosterone concentration continued after ACTH was suppressed by dexamethasone pretreatment. These changes, in the absence of a consistent significant correlation with PRA and sodium and potassium concentrations, further suggest that another factor(s) may be important in controlling aldosterone production in recumbent normal subjects.