Evaluation of a single seizure: guidelines for advance practice nurses

Deciding whether or not to treat a client after a single seizure can be challenging for the clinician. The risk of seizure recurrence is greatest in the first six months after the initial episode. The decision to treat a single seizure should be based on diagnostic and clinical findings that assess the client's risk for recurrence. When making treatment decisions, the clinician must consider the benefits and risks of single-seizure therapy. Careful consideration should be given to differential diagnosis, factors that induce symptomatic seizures and risk factors for epilepsy.

Determination of 8-oxoguanine in human plasma and urine by high-performance liquid chromatography with electrochemical detection

A highly sensitive and selective method for determining 8-oxoguanine in plasma and urine was developed by high-performance liquid chromatography with electrochemical detection. The compound was separated by gradient elution on a C18 reversed-phase column with a mobile phase of acetonitrile and 0.1 M sodium acetate, pH 5.2. 8-Hydroxy-2'-deoxyguanosine was used as internal standard. 8-Oxoguanine was detected electrochemically by setting the potential to +300 mV vs. Pd reference. The sensitivity of the assay was 22 ng/ml with a signal-to-noise ratio of 7:1. The within-day relative standard deviations for 8-oxoguanine quality control samples with concentrations of 3340, 1340 and 84 ng/ml were 3.6, 4.3 and 5.7% for plasma, and 4.1, 4.6 and 6.2% for urine, respectively. The day-to-day relative standard deviations for the same samples were 3.8, 6.8 and 7.1% for plasma, and 3.9, 7.0 and 7.9% for urine, respectively. The method is designed to study the pharmacokinetics and metabolic fate of O6-benzylguanine in a phase I clinical trial. Previously, O6-benzyl-8-oxoguanine was identified as the primary metabolite of O6-benzylguanine in humans. We now demonstrate that 8-oxoguanine is a further metabolite of O6-benzylguanine.

Phase I study of the novel cyclic AMP (cAMP) analogue 8-chloro-cAMP in patients with cancer: toxicity, hormonal, and immunological effects

The cyclic AMP (cAMP)-dependent protein kinase regulatory subunit RI is overexpressed in cancer cells. 8-Chloro-cAMP (8-Cl-cAMP) is an RII site-specific analogue that down-regulates RI and inhibits the growth of a wide range of cancer cells in vitro and in vivo. We performed a Phase I trial of 8-Cl-cAMP in 32 patients with malignancies that were refractory to standard treatments. 8-Cl-cAMP was initially given in a 1-month cycle by constant infusion at 0.005 mg/kg/h for 21 days, followed by 1 week of rest. The dose was escalated to 0.045 mg/kg/h, but hypercalcemia became the dose-limiting toxicity. The length of drug administration was, therefore, reduced to 5 days per week for the first 3 weeks of the cycle, but it was not possible to increase the drug dose without producing hypercalcemia. Hence, the length of drug administration was reduced to 3 days per week for the first 3 weeks of the cycle. The maximum tolerated dose for this regimen was 0.15 mg/kg/h, and the dose-limiting toxicities were reversible hypercalcemia and hepatotoxicity. Stable disease for > or =4 months was observed in two patients treated at > or =0.045 mg/kg. cAMP-dependent protein kinase is involved in hormone- and cytokine-mediated signaling, and so representative hormone, cytokine, and peripheral lymphocyte subsets were measured. The drug had a parathyroid hormone-like effect on calcium homeostasis and significantly increased circulating luteinizing hormone and 17-hydoxyprogesterone levels (P < 0.02 and P < 0.0006, respectively). We conclude that 8-Cl-cAMP is well tolerated without attendant myelotoxicity, and in this study, it was associated with biological effects. In Phase II studies, a dose of 0.11 mg/kg/h for 3 days per week would be appropriate.

Phase I study of intrapleural batimastat (BB-94), a matrix metalloproteinase inhibitor, in the treatment of malignant pleural effusions

Tumor cells and associated stromal cells secrete matrix metalloproteinases (MMPs), contributing to invasion, angiogenesis, and metastasis. Batimastat (BB-94) is a broad-spectrum MMP inhibitor that causes resolution of ascites and/or tumor growth delay in animal models of breast, ovarian, and colorectal cancer. We recruited 18 patients with cytologically positive malignant pleural effusions into a Phase I study of intrapleural BB-94. Three patients received single doses of BB-94 at each dose level: 15, 30, 60, 105, 135, and 300 mg/m2. Two patients were retreated with a second course at 60 and 105 mg/m2. BB-94 was detectable in plasma 1 h after intrapleural administration, and peak levels of 20-200 ng/ml occurred after 4 h to 1 week. BB-94 persisted in the plasma for up to 12 weeks, at levels exceeding the IC50s for target MMPs. Peak values were higher, and persistence in the plasma was longer after higher doses of BB-94. The treatment was well tolerated. Toxic effects included low-grade fever for 24-48 h (6 of 18 patients, 33%) and reversible asymptomatic elevation of liver enzymes (8 patients, 44%). Toxicity seemed unrelated to BB-94 dose or plasma levels. Sixteen patients evaluable for response required significantly fewer pleural aspirations in the 3 months after BB-94 compared with the 3 months before. Seven patients (44%) required no further pleural aspiration until death/last follow-up. After 1 month, patients treated with 60-300 mg/m2 BB-94 had significantly better dyspnea scores, indicating improved exercise tolerance, compared with baseline scores the day after BB-94. The maximum tolerated intrapleural dose remains to be defined, but it is clear that intrapleural BB-94 is well tolerated, with evidence of local activity.

NPR-A-Deficient mice show increased susceptibility to hypoxia-induced pulmonary hypertension

BACKGROUND

Mice in which the gene encoding NPR-A, a guanylyl cyclase-linked natriuretic peptide receptor, has been disrupted were used to examine the contribution of natriuretic peptides to maintaining pulmonary vascular homeostasis in normal- and low-oxygen environments.

METHODS AND RESULTS

Wild-type (+/+), heterozygous (+/-), and homozygous null mutants (-/-) were studied. The response of the pulmonary vasculature to atrial, B-type, and C-type natriuretic peptides (ANP, BNP, and CNP) during acute hypoxia was studied in isolated perfused lungs. Right ventricular systolic pressure (RVSP), RV weight, and pulmonary vascular remodeling were measured in each genotype exposed to normal air and after 7 and 21 days in a hypoxic atmosphere (10% O2). ANP and BNP (300 ng) reduced pulmonary artery pressure during acute hypoxia-induced pulmonary vasoconstriction in +/+ mice, but this effect was attenuated in +/- and absent in -/- mice. CNP (600 ng) had little effect in all 3 genotypes. RVSP and RV weight were similar in the 3 genotypes housed in a normal-O2 environment. Seven and 21 days of hypoxia produced a pronounced and significantly greater increase in RVSP and RV weight in -/- mice compared with +/+ or +/- mice and more rapid muscularization of distal pulmonary arterioles.

CONCLUSIONS

ANP and BNP do not contribute to maintaining normal pulmonary artery pressure but play an important role in attenuating the pulmonary vascular response to hypoxia. NPR-A mediates the vasorelaxant effect of ANP in pulmonary vasculature.

Regulation of the Mr 72,000 type IV collagenase by the type I insulin-like growth factor receptor

The Mr 72,000 type IV collagenase [matrix metalloproteinase 2 (MMP-2)] is known to play a central role in the process of invasion and metastasis, but its regulation is not clearly understood. We investigated the role of the type I insulin-like growth factor (IGF-I) in the regulation of tumor cell invasion and the synthesis of MMP-2. Highly invasive murine Lewis lung carcinoma subline H-59 cells, in which expression of the IGF-I receptor (IGF-IR) was blocked by antisense mRNA, had a significantly reduced invasion in reconstituted basement membrane (Matrigel) as compared with that of controls. These cells had a decrease of up to 6-fold in the level of MMP-2 mRNA transcripts, as assessed by reverse transcription-PCR, and a corresponding reduction in protein synthesis, as assessed by the Western blot assay and gelatin zymography. Conversely, overexpression of IGF-IR in a second, poorly invasive carcinoma subline (M-27) with low endogenous levels of the receptor increased MMP-2 mRNA and protein expression by up to 7.5- and 4-fold, respectively. Ligand-mediated activation of the IGF-IR induced MMP-2 synthesis in both cell types. The results identify IGF-I as a regulator of MMP-2 expression and cellular invasion.

Structural determination in AUF1 required for high affinity binding to A + U-rich elements

AUF1 is a RNA-binding protein that contains two non-identical RNA recognition motifs (RRMs). AUF1 binds to A + U-rich elements (AREs) with high affinity. The binding of AUF1 to AREs is believed to serve as a signal to a mRNA processing pathway which degrades mRNAs encoding many cytokines, oncoproteins and G protein-coupled receptors. Because the ARE-binding activity of AUF1 appears central to the regulation of many important genes, we analyzed the domains of the protein that are important for this activity. Examination of the binding affinity of various mutants indicates that both RRMs may be required for binding. However, they are not sufficient. Highest affinity binding requires an alanine/glycine-rich region of the N-terminus and a short glutamine-rich region in the C-terminus. The N-terminus is required for dimerization of AUF1. However, AUF1 binds an ARE as a hexameric protein. Thus protein-protein interactions are important for high affinity ARE-binding activity of AUF1.

Enhanced invasion and liver colonization by lung carcinoma cells overexpressing the type 1 insulin-like growth factor receptor

The receptor for the type 1 insulin-like growth factor (IGF-1R) and its ligands IGF-1 and IGF-2 play important roles in the maintenance of the malignant phenotype. In previous studies with two sublines of the Lewis lung carcinoma (H-59 and M-27, expressing high and low levels of IGF-1R, respectively) we have shown that receptor levels in these tumor cells correlated with metastasis to the liver. In the present study we asked whether the metastatic properties can be modulated by increasing receptor levels. M-27 carcinoma cells were transfected with a plasmid vector expressing a full-length human IGF-1R cDNA. Expression of the human receptor in the stable transfectants was confirmed by RT-PCR and immunoprecipitation analysis. These cells had an enhanced proliferative response to IGF-1 and hepatocyte-conditioned medium and an increased clonogenic potential in semisolid medium. Moreover, they acquired an invasive potential as measured in the reconstituted basement membrane (Matrigel) invasion assay. When inoculated via the splenic/portal route in vivo, these cells but not mock-transfected cells gave rise to multiple tumor nodules. The results suggest that IGF-1R can modulate several cellular functions which impact on the metastatic phenotype including invasion and liver colonization.

Accounting for two population turnarounds in nonmetropolitan America

"The turnaround [in U.S. rural-to-urban migration] of the 1970s, the metropolitan resurgence of the 1980s, and the rural rebound of the 1990s [have been] described as three unanticipated changes in migration.... [This chapter] compares the magnitude of the three changes in net migration and contrasts the two nonmetropolitan turnarounds.... The results support a view of the 1970s turnaround as the outcome of long-term deconcentrating trends that were interrupted from the late 1970s to the late 1980s by circumstances that favored metropolitan areas. The return of nonmetropolitan territory to net in-migration in the 1990s appears to be due in part to favorable economic conditions that allow more people to act on preferences for smaller places."

Conservation approach to duplication of the small bowel

BACKGROUND/PURPOSE

Intestinal duplication and adjacent small bowel share a single mesentery with straight arteries from the arcade supplying the normal bowel or supplying the duplication. The usual surgical management is resection of the duplication and the adjacent bowel with end to end anastomosis of the remaining bowel. The aim of this study was to conduct an experimental study of blood supply to the bowel and consequences of ligation of the straight arteries to one side of the bowel, and attempt preservation of all normal bowel in patients who have duplication.

METHODS

The study was carried out on 25 New Zealand white rabbits. The intestinal blood supply of three groups of rabbits (control, acute, and chronic) have been studied by perfusion, microdissection and stereoscopic microscopic examination, and scanning electron microscopy after impregnation with gold, after ligation of the straight arteries to one side of the intestine. From 1992 to 1996, 14 patients who had duplication of the bowel were treated by resection of duplication and conservation of bowel. They have had follow-up for up 4 years. Barium studies have been performed.

RESULTS

In the animal studies, the bowel was viable and functioning normally in all animals but numerous adhesions developed. The results presented show no impairment in bowel function in human studies.

CONCLUSION

Ligation of the straight arteries to the duplication with resection of only the duplication is a satisfactory approach to conservation of bowel in patients who have duplication.

A novel cyclic adenosine monophosphate analog induces hypercalcemia via production of 1,25-dihydroxyvitamin D in patients with solid tumors

The treatment of cancer patients with conventional chemotherapy is sometimes associated with severe systemic toxicity and only a minimal survival benefit. Because of this, new less toxic and more efficacious treatments have been sought. 8-Chloro-cAMP (8-Cl-cAMP) is one of a new generation of anticancer drugs that act at the level of signal transduction. In preclinical models, 8-Cl-cAMP modulates protein kinase A (PKA) leading to growth inhibition and increased differentiation of cancer cells. 8-Cl-cAMP was given to 16 patients with advanced cancer as an infusion via an indwelling subclavian venous catheter. We showed that 8-Cl-cAMP had a parathyroid hormone-like effect leading to increased synthesis of renal 1,25-dihydroxyvitamin D [up to 14 times the baseline value, median 3.6 times; P = 0.00001 (Student's paired t test)]. This produced the dose-limiting toxicity of reversible hypercalcemia that could not be controlled by the administration of either pamidronate or dexamethasone. The treatment was otherwise well tolerated, and other cAMP-dependent pathways (cortisol and TSH) were not affected, emphasizing the marked differences between organs in their sensitivity to this cAMP analog. Our results have shown that 8-Cl-cAMP is biologically active, and it is feasible that if the hypercalcemia can be controlled, then this drug may have a role as a single agent, or as a short infusion between cycles of chemotherapy.

Structural determinants in AUF1 required for high affinity binding to A + U-rich elements

AUF1 is an RNA-binding protein that contains two nonidentical RNA recognition motifs (RRMs). AUF1 binds to A + U-rich elements (AREs) with high affinity. The binding of AUF1 to AREs is believed to serve as a signal to an mRNA-processing pathway that degrades mRNAs encoding many cytokines, oncoproteins, and G protein-coupled receptors. Because the ARE binding activity of AUF1 appears central to the regulation of many important genes, we analyzed the domains of the protein that are important for this activity. Examination of the RNA binding affinity of various AUF1 mutants suggests that both RRMs may be required for binding to the human c-fos ARE. However, the two RRMs together are not sufficient. Highest affinity binding of AUF1 to an ARE requires an alanine-rich region of the N terminus and a short glutamine-rich region in the C terminus. In addition, the N terminus is required for dimerization of AUF1. However, AUF1 binds an ARE as a hexameric protein. Thus, protein-protein interactions are important for high affinity ARE binding activity of AUF1.

The practical aspects of epilepsy: critical components of comprehensive patient care

Patients with epilepsy are often exposed to difficult social dilemmas, some of which may be more challenging than the actual seizure. Although all patients with chronic conditions experience social hardships, the epileptic patient may be at greater risk for social difficulties. Due to unjust restrictions and an overall lack of emphasis on psychosocial matters, patients with epilepsy may be wrongfully denied participation in routine activities. These patients may also lack an understanding of appropriate prevention measures related to self injury. Appropriate restrictions for patients with epilepsy include driving and selected extra-curricular activities. The home environment is particularly dangerous for epilepsy patients. Other social issues for epilepsy patients include suicide attempts, employment and alcohol consumption.

The "clean break" revisited: is U.S. population again deconcentrating?

"The Hoover index, calculated across counties and larger spatial units, is again declining--signalling a renewal of population deconcentration in the United States. After increasing for several decades, the index declined in the 1970s when nonmetropolitan population growth surged past metropolitan-area growth, but the index rose in the 1980s as metropolitan population growth recovered and surpassed nonmetropolitan growth. We update these trends, introducing careful controls for changes in metropolitan-area boundaries, and we incorporate a ¿functional urban region' approach. Although the nonmetropolitan population growth rate is still below the metropolitan rate, we conclude that in the 1990s some features of the ¿turnaround' of the 1970s have returned."

[Studies on purification and some properties of nisin from Lactococcus lactis subsp. lactis Al2]

Nisin from Lactococcus lactis subsp. lactis AL2 was extracted with n-propanol from NaCl-saturated culture and purified by ion-exchange chromotography on CM-Sephadex C-25. Nisin was purified 1.63 fold with a yield of 41.7%. The molecular weight of nisin was determined by SDS-PAGE to be about 3500. Nisin activity was stable at low pH and sensitive to digestion by a-chymotrypsin. Nisin is capable of inhibiting a broad range of gram-positive bacteria. In contrast, the gram-negative bacteria, yeasts, molds and Nip+ L. lactis subsp. lactis ATCC11454 were not inhibited.

Epilepsy: a review of seizure types, etiologies, diagnosis, treatment, and nursing implications

Critical care nurses must be able to adequately identify and document seizure activity, perform appropriate interventions, and recognize signs of AED toxicity. Critical care nurses not only share the responsibility of taking care of epilepsy patients, but also must help in valuable patient and family education as it relates to long-term management. Becoming better informed of the plan of care for epilepsy patients helps optimize expected outcomes and enables patients and families to manage this illness better.

Epilepsy: a review of seizure types, etiologies, diagnosis, treatment, and nursing implications

Critical care nurses must be able to adequately identify and document seizure activity, perform appropriate interventions, and recognize signs of AED toxicity. Critical care nurses not only share the responsibility of taking care of epilepsy patients, but also must help in valuable patient and family education as it relates to long-term management. Becoming better informed of the plan of care for epilepsy patients helps optimize expected outcomes and enables patients and families to manage this illness better.

Localization and physical mapping of genes encoding the A+U-rich element RNA-binding protein AUF1 to human chromosomes 4 and X

Messenger RNAs encoding many oncoproteins and cytokines are relatively unstable. Their instability, which ensures appropriate levels and timing of expression, is controlled in part by proteins that bind to A+U-rich instability elements (AREs) present in the 3'-untranslated regions of the mRNAs. cDNAs encoding the AUF1 family of ARE-binding proteins were cloned from human and murine cDNA libraries. In the present study monochromosomal somatic cell hybrids were used to localize two AUF1 loci to human chromosomes 4 and X. In situ hybridization analyses using P1 clones as probes identified the 4q21.1-q21.2 and Xq12 regions as the locations of the AUF1 genes.

Self-concept and behavior in adolescent girls with Turner syndrome: potential estrogen effects

Data on self-concept and behavior were gathered from 31 girls with Turner syndrome (TS) followed longitudinally between the ages of 12 and 16 and from 89 normal control girls recruited from public schools and assessed cross-sectionally. The two groups of girls were similar in age and racial composition. The girls with TS were treated with estrogen replacement therapy in increasing doses between the ages of 12 and 16 (100-400 ng/kg-day ethinyl estradiol). Their self-reported self-esteem and psychological well-being (Piers-Harris Self-Concept Scale) revealed significant improvement over time for most scales as well as the total score (P < 0.001). Parents reported improvement in problem behaviors, as reflected in the Child Behavior Checklist (CBCL) scales: Behavior Total, Externalizing Behavior, Aggressive Behavior, and Social Problems Behavior scales (all P < 0.001). Analysis of covariance comparing normal controls to the TS subjects revealed that at age 12 yr, TS and normal subjects differed significantly for the School Social Competency sub-scale and the Social Problems Behavior subscale (all P < 0.001). Girls with TS resembled the normal controls on all CBCL scales by ages 14-15 yr. Thus, we found improved self-concept both by self- and parental report in estrogen-treated girls with TS followed longitudinally through adolescence. An analogous correlation with age was not seen in the cross-sectional normal control sample. These findings support positive effects of estrogen on psychological well-being in girls with TS and underscores the need to initiate estrogen replacement therapy by ages 12-14 yr in this population.

Pesticide appliers with mixed pesticide exposure: G-banded analysis and possible relationship to non-Hodgkin's lymphoma

To further investigate the possible relationships between agricultural pesticide exposure and the increased risk of non-Hodgkin's Lymphoma among farm workers in the north central United States, we performed G-banded chromosome analyses of peripheral blood from workers classified according to primary types of pesticide exposure: herbicides (n = 20), insecticides (n = 18), fumigants (n = 23), and occupationally unexposed controls (n = 33). Significantly increased rearrangement frequencies were demonstrated in fumigant and insecticide appliers compared to control subjects. At certain chromosome bands there were significant excesses of breaks observed in pesticide appliers, but no breaks were observed in controls. Some of these bands contained genes with potential implications for cancer risk, including oncogenes and genes involved in tumor suppression and apoptosis. Of particular interest with regard to lymphoma risk were the excess rearrangement and breaks involving band 14q32 in fumigant appliers and the excess breaks involving band 18q21 in herbicide appliers; translocations linking 14q32 and 18q21 are the most common rearrangements observed in non-Hodgkin's lymphoma patients. The potential pathobiological relevance of these cytogenetic events warrants additional investigation at the molecular level.

An instrument to assess the oral health status of nursing home residents

This article presents data from the development and testing of an instrument to evaluate the oral health of nursing home residents by nursing personnel (RNs, LVNs, and CNAs). After the instrument was developed, nursing staff were taught to do a brief oral health status examination (BOHSE). Using the instrument, a dentist examined 100 residents; the examination was repeated on the same residents by each category of nurse examiners. Correlation coefficients indicate that statistically significant interrater reliability between the three categories of nursing personnel and the dentist was established, suggesting that nursing staff can be taught to evaluate the oral health of residents. Replication of the study in multiple sites is recommended.