Mouse down-regulated in adenoma (DRA) is an intestinal Cl(-)/HCO(3)(-) exchanger and is up-regulated in colon of mice lacking the NHE3 Na(+)/H(+) exchanger

Mutations in human DRA cause congenital chloride diarrhea, thereby raising the possibility that it functions as a Cl(-)/HCO(3)(-) exchanger. To test this hypothesis we cloned a cDNA encoding mouse DRA (mDRA) and analyzed its activity in cultured mammalian cells. When expressed in HEK 293 cells, mDRA conferred Na(+)-independent, electroneutral Cl(-)/CHO(3)(-) exchange activity. Removal of extracellular Cl(-) from medium containing HCO(3)(-) caused a rapid intracellular alkalinization, whereas the intracellular pH increase following Cl(-) removal from HCO(3)(-)-free medium was reduced greater than 7-fold. The intracellular alkalinization in Cl(-)-free, HCO(3)(-)-containing medium was unaffected by removal of extracellular Na(+) or by depolarization of the membrane by addition of 75 mM K(+) to the medium. Like human DRA mRNA, mDRA transcripts were expressed at high levels in cecum and colon and at lower levels in small intestine. The expression of mDRA mRNA was modestly up-regulated in the colon of mice lacking the NHE3 Na(+)/H(+) exchanger. These results show that DRA is a Cl(-)/HCO(3)(-) exchanger and suggest that it normally acts in concert with NHE3 to absorb NaCl and that in NHE3-deficient mice its activity is coupled with those of the sharply up-regulated colonic H(+),K(+)-ATPase and epithelial Na(+) channel to mediate electrolyte and fluid absorption.

Nurses take. Therapeutic change into their own hands

As part of a continuous quality improvement program, a hospital implements a nurse-driven milieu therapy plan for substance abuse patients.

Using literature to create cultural competence

PURPOSE

To describe how literature can be used to promote cultural competence. Cultural competence is essential for nurses who practice in diverse societies like the United States.

ORGANIZING FRAMEWORK

Cultural competence is viewed as a dynamic process of framing assumptions, knowledge, and meanings from a culture other than one's own. Selected excerpts from "The Color Purple" by Alice Walker are used to illustrate the method. Isler's readers' response theory serves as a guide for imaginative engagement and reflective discussion of the concept of health.

CONCLUSIONS

Literature helps to dispel the false notion of a monolithic culture. Reflecting on reputable literature helps us hear the stories of those we hope to help and heal.

Preliminary evidence for cyclosporin A as an alternative in the treatment of recalcitrant juvenile rheumatoid arthritis and juvenile dermatomyositis

OBJECTIVE

To evaluate the safety and efficacy of cyclosporin A (CyA) with and without methotrexate (MTX) in refractory juvenile rheumatoid arthritis (JRA) and juvenile dermatomyositis (JDMS).

METHODS

Twenty-two patients (17 with JRA, 5 with JDMS) with refractory disease were studied retrospectively. All received CyA at a mean dose of 3.2 mg/kg/day over a mean period of 16 mo (range 6-42). All other medications except nonsteroidal antiinflammatory drugs, prednisone, and hydroxychloroquine were discontinued. In addition, 16/22 patients received concomitant MTX.

RESULTS

Improvements in laboratory variables, joint counts, joint swelling, and morning stiffness were observed in most of the children with JRA. Muscle strength increased and muscle enzyme levels decreased in the patients with JDMS. CyA treatment permitted prednisone to be discontinued in 5/20 and reduced by greater than 50% in 10/20 patients. There was no evidence of hepatic or bone marrow toxicity or lymphoproliferative disease. Serum creatinine increased in 13/22 patients, but the actual values all remained within normal limits.

CONCLUSION

CyA may be an effective agent in the treatment of refractory JRA and JDMS and concomitant MTX seems to be well tolerated. These preliminary data also suggest that combined CyA/MTX therapy may be associated with further improvement in clinical outcome.

The evaluation and treatment of seizures in the emergency department

One to two percent of visits to the emergency department are due to seizures. These patients may require aggressive stabilization and resuscitation and concurrent implementation of diagnostic testing, monitoring, and pharmacologic interventions. Seizures are usually a manifestation of an underlying pathology which requires thorough evaluation, including a careful history, physical examination, laboratory work-up, and electroencephalographic and neuroimaging studies as dictated by clinical suspicion. The evaluation and treatment of seizures in the emergency department must be comprehensive, including giving consideration to the patient's medical and social resources.

Management of life-threatening asthma in the emergency department

Acute asthma exacerbations are frequent presentations to the emergency department. Those patients who deteriorate despite nebulized beta-agonist therapy and intravenous steroids are experiencing a life-threatening event. They pose a significant management challenge to the emergency physician. This review describes the pharmacologic options and techniques for mechanical ventilation which are available in resuscitating these patients.

A six-year follow-up study of smoking habits and microvascular complications in young adults with type 1 diabetes

One hundred insulin-dependent diabetic patients (age < 45 years, 53 smokers) were followed for six years. The age, duration of diabetes and mean glycated haemoglobin levels, were comparable between the smokers and non-smokers. Microvascular complications (retinopathy and increased urine albumin excretion) were commoner and more severe in the smoking group at six years, particularly in heavy smokers. Of the 45 original smokers reviewed at six years, 12 (27%) had stopped, six of whom had developed microvascular complications. Only two of the 'heavy' initial smokers, likely to be at most risk, had stopped smoking, and three original non-smokers had started smoking.

Diurnal variation in blood pressure in insulin-dependent diabetic smokers and non-smokers with and without microalbuminuria

In subjects with essential hypertension, loss of the normal nocturnal dip in blood pressure is associated with a greater risk of developing end-organ complications. In subjects with diabetes, smoking carries a similar association. To assess whether these factors may have an aetiological and synergistic role in the vascular complications of diabetes, 24-hour blood pressure monitoring was performed in insulin-dependent diabetic (IDDM) patients with normal albumin excretion (n = 19) and microalbuminuria (n = 21) of comparable age and duration of diabetes, and with no evidence of autonomic neuropathy or hypertension. The potential influence of smoking was examined by subdividing the groups, depending on smoking status. Ten of the microalbuminuric group and 9 of the normoalbuminuric group were current smokers, the remaining patients never having smoked. There was a significant difference between mean (+/-SD) daytime vs nocturnal blood pressure in patients with normal albumin excretion (114 +/- 3/70 +/- 4 vs 102 +/- 3/62 +/- 3 mmHg; p < 0.001) and microalbuminuria (109 +/- 5/75 +/- 5 vs 101 +/- 3/65 +/- 4 mmHg; p < 0.001) but mean blood pressure values did not differ significantly between the groups. A similar fall in nocturnal blood pressure was found in smokers and non-smokers with and without microalbuminuria (p < 0.001), but there was no difference between the mean blood pressure values in the different subgroups. In conclusion, normotensive IDDM patients, who do not have autonomic neuropathy, retain a significant diurnal variation in blood pressure, irrespective of smoking habit or presence of microalbuminuria.

Genomic regions regulating imprinting and insulin-like growth factor-II promoter 3 activity in transgenics: novel enhancer and silencer elements

Transgenic lines (89) were made with constructs containing eight different combinations of candidate regulatory elements from the insulin-like growth factor-II (Igf2)-H19 region of mouse chromosome 7. In all constructs, promoter 3 of Igf2 was attached to a firefly luciferase reporter gene. Promoter 3 was the common element that imposed a decrease in reporter activity similar to that of endogenous Igf2 after birth. The specific activity of the reporter was measured on the day of birth in the liver and the brain, after each transgene had been transmitted by either the father or the mother. This procedure demonstrated that the quantity and organ distribution of expression from this promoter can be regulated by each element. The following new information was obtained. (a) The 5' differentially methylated region of Igf2 inhibits promoter 3 in the liver. (b) The conserved DNase I-hypersensitive Middle region between Igf2 and H19 is an enhancer of promoter 3 in the brain. (c) The H19 promoter inhibits Igf2 promoter 3 in the brain. The results confirmed that the H19 enhancer is a strong enhancer of promoter 3 in the liver. A new finding was that one genomic region regularly imposed imprinted gene expression. This was the H19 enhancer, and this region was sufficient to give higher expression on maternal transmission in the majority of transgenic lines. The full data are reported in Supplementary Publication SUP 50180 (8 pages), which has been deposited at the British Library Document Supply Centre, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1997) 21, 8-10.

Self-assessed versus expert-assessed occupational exposures

While self-response to a checklist of substances may be a convenient and inexpensive method for obtaining information on occupational exposure, the validity of such information has not been evaluated. The objective of this report is to provide some evidence concerning validity of self-reported occupational exposures. In the context of a large case-control study, it was possible to compare self-reports with expert assessment, in which a team of industrial hygienists and chemists examined each job history individually and decided on likelihood of exposure. The subjects were 1,910 males who had participated in a population-based case-control study of cancer and occupational exposures conducted in Montreal, Canada, between 1979 and 1985. For each of 11 substances, the two methods of exposure assessment were compared by means of a kappa statistic and by computing the sensitivity and specificity of self-assessment against expert assessment. Kappa values ranged from 0.33 to 0.64. Compared with the expert assessment, specificities of the self-assessment were generally high (0.83-0.97, with a median of 0.90), but sensitivities were low (0.39-0.91, with a median of 0.61). The authors conclude that self-reports of occupational exposure are not sufficiently accurate to warrant their sole use in most community-based studies.

Human papillomavirus DNA in invasive cervical carcinomas and its association with patient survival: a nested case-control study

This study sought to examine the association between the presence of human papillomavirus (HPV) DNA in invasive cervical cancer and prognosis. A case-control study was undertaken nested in a cohort of 208 patients with invasive cervical carcinoma in Montreal. All 40 deceased patients formed the case groups. A control group of equal size was selected by matching to each case (1:1) a patient of the same age and year of admission who had survived her disease. HPV DNA was detected by the use of a PCR protocol. The odds ratio (OR) for cervical cancer death was computed by logistic regression. Detection of HPV, particularly of types 16 and 18, was negatively correlated with disease stage and histological grade. The OR for death was 0.27 [95% confidence interval (CI), 0.1-0.8] for those whose tumors were positive for HPV DNA versus those in whom HPV DNA was not detected. After adjusting for the confounding effects of stage and grade, the prognostic effect was somewhat reduced, with an OR of 0.34 (CI, 0.1-1.1), which was no longer significant. The magnitude of the HPV-survival association was not altered when the analyses were restricted to carcinomas of stages I and II. Regardless of the mechanism for the prognostic role, detection of HPV DNA in primary tumors may play an important adjunct role in assessing prognosis of patients with invasive cervical cancer.

The rat cim effect: TAP allele-dependent changes in a class I MHC anchor motif and evidence against C-terminal trimming of peptides in the ER

Functional polymorphism in the rat peptide transporter associated with antigen processing (TAP) changes the peptide pool available for binding and presentation by a class I MHC allele, RT1.Aa. The peptide binding motif for RT1.Aa, determined by stabilization with synthetic peptides, included a strong preference for arginine at the peptide C terminus. Analysis of natural peptides bound to RT1.Aa by both pool sequencing and anhydrotrypsin chromatography revealed that TAP polymorphism determined the presence or absence of arginine as the peptide C-terminal residue. This result highlights the in vivo impact of TAP-peptide selectivity, and provides evidence against a high rate of generation of new C termini by protease activity in the endoplasmic reticulum.

Salivary count of Streptococcus mutans in elementary school children

Previous studies have documented that persons with high levels of Streptococcus mutans are "at risk" for dental caries. The objective of this study was to identify children at an early age who were "at risk" for caries. The sample consisted of 77 school children aged 9-13 years old. The majority of the sample was African-Americans (55.8%). Approximately 51% were females. The Dentocult SM Strip Mutans Test was used to estimate the S. mutans count in saliva. The method is based on the use of a selected culture broth and the adhere S. mutans count of < 1,000,000 bacteria ml saliva and children with S. mutans count of < 1,000,000 were classified as "low risk" for caries. The DMF-T was used to estimate the number of decayed, missing and filled teeth. The decayed mean score = 1.85; range = 0-9. Only two children had teeth missing (one in each). The number of filled teeth was low; mean = .88; range = 0-6. The DMF-T mean score was 2.75; range = 0-9. Correlations were sought between levels of S. mutans rates and decayed teeth. Low, but nonsignificant, correlations were found between S. mutans and decayed teeth (r = .20). This trend continued for S. mutans levels and the DMF-T (r = .16). Analysis of Variance Test (ANOVA) indicated a significant effect by sex on the levels of S. mutans P < .05 (females had higher S. mutans levels than males). There was no significant difference or interaction noted in DMF-T scores by sex or race. In addition no significant difference was noted in the number of decayed teeth by sex or race. Our results indicate that females in this age group are potentially at greater risk for dental caries than their male counterparts due to the observed higher levels of S. mutans. This observation deserves further study.

Mammary cancer in transgenic mice expressing insulin-like growth factor II (IGF-II)

The effect of insulin-like growth factor II (IGF-II) on tumour development in the mouse mammary gland was studied. To promote extra IGF-II expression in the mammary gland, sheep beta-lactoglobulin regulatory elements were attached to the coding regions of the mouse Igf-2 gene and injected into the pronuclei of mouse zygotes. Mammary tumours developed in each of the four independent lines of mice which expressed transgene IGF-II in the gland. Tumours from two of the lines grew after transplantation to both male and female hosts. Primary tumours contained stromal and epithelial regions, but the tumours were dominated by mammary adenocarcinoma after transplantation. The tumours expressed high levels of Igf-2 mRNA transcribed from the integrated transgenes.

Sulfated oligosaccharides promote hepatocyte growth factor association and govern its mitogenic activity

Hepatocyte growth factor (HGF) is a potent mitogen, motogen, and morphogen for various epithelial cell types. The pleiotropic effects of HGF are mediated by its binding to a specific high affinity receptor, c-Met. In addition, HGF binds to heparan sulfate proteoglycans on cell surfaces and within the extracellular matrix. Incubation of HGF with 0.1, 1.0, and 10 micrograms/ml of heparin, heparan sulfate, or dextran sulfate resulted in a concentration-dependent increase in mitogenic potency in a primary rat hepatocyte bioassay, whereas sodium sulfate or fucoidan did not. Although co-incubation of HGF with sulfated compounds that enhanced HGF-dependent mitogenesis did not alter the binding isotherm of HGF for the c-Met receptor in a solid phase assay, an increase in autophosphorylation of the c-Met receptor in intact A549 cells was observed upon their addition. A series of chemically sulfated malto-oligosaccharides varying in unit size and charge was tested in the bioassay in order to provide additional insights into the nature of the HGF-heparin interaction. While sulfated di-, tri-, tetra-, and pentasaccharides did not significantly potentiate HGF-dependent mitogenesis, larger oligosaccharides such as the sulfated hexa-, hepta-, or a sulfated oligosaccharide mixture containing decasaccharides resulted in an approximate 2-, 4-, and 7-fold enhancement, respectively. We observed a correlation between the sulfated oligosaccharide preparations that enhanced mitogenic potency and those that promoted HGF oligomerization in vitro, as measured by gel filtration and analytical ultracentrifugation. These findings indicate that heparin-like molecules can stabilize HGF oligomers, which may facilitate c-Met receptor dimerization and activation.

High plasma insulin-like growth factor-II and low lipid content in transgenic mice: measurements of lipid metabolism

Transgenic mice were made by introducing extra copies of the mouse insulin-like growth factor-II (IGF-II) gene driven by the bovine keratin 10 promoter (BKVI). The adult plasma IGF-II levels were elevated at least three times in one line. In this line, there was a lower lipid content of both brown and white adipose depots at 2-4 months of age, and 40% less fat in the carcass at 7-9 months. The low lipid phenotype was not detected in the carcass at 2 weeks after birth. The lean characteristic was attributed to circulating IGF-II because the transgene was not expressed in fat. At 2-4 months of age, the transgenes oxidized more oral lipid, and less of this lipid was incorporated into the whole body and the epididymal fat. In contrast, the interscapular brown adipose tissue maintained lipid incorporation and lipoprotein lipase activity despite its reduced size. The altered activity of the brown adipose tissue may account for the gradual onset and persistence of the lean feature of the transgenic mice. There were no substantial changes in lipogenesis which could account for the low fat content. The plasma levels of IGF-I, insulin, glycerol, non-esterified fatty acids, triacylglycerols and glucose were not greatly changed and the pituitary GH content was within the normal range.

Surgical repair of iatrogenic soft palate defects in two horses

A 4-year-old Thoroughbred filly was referred for evaluation of a soft palate defect that had been created several weeks earlier during surgical correction of epiglottic entrapment, performed transorally. Surgical correction of the defect was performed via mandibular symphysiotomy. At 85 days after repair, the horse raced successfully. A 2-year-old Thoroughbred filly was admitted for evaluation and treatment of epiglottic entrapment. The soft palate was lacerated during transnasal division of the entrapping membrane. A 2-cm full-thickness soft palate laceration was repaired transorally.

The tolerability of dothiepin: a review of clinical studies between 1963 and 1990 in over 13,000 depressed patients

1. A total of 13,834 depressed patients were exposed to dothiepin most frequently at a dose of 150 mg/day and over 6 weeks, in 116 clinical studies between 1963 and 1990. 2. Overall, 2,066 (15%) patients were withdrawn prematurely from dothiepin for a variety of reasons, the most commonly specified reason being due to drug-related events in 500 (4%) patients. 3. In the remaining 11,768 patients, there were 9,312 reports of unwanted events most typically associated with the pharmacological effects of a tricyclic antidepressant although no serious sequelae were reported. 4. This review indicates that the incidence of serious adverse events associated with dothiepin at therapeutic doses is very low.

Disproportionate growth in mice with Igf-2 transgenes

Injection transgenesis was used to study the long-term effects of excess insulin-like growth factor II on mouse growth and differentiation. By using a construct in which the coding region of the mouse insulin like growth factor II gene (Igf-2) was placed under the control of a keratin gene promoter, four transgenic lines were established, all of which displayed overgrowth of the skin as judged by wrinkling. In addition to high levels of expression in the skin, transgene transcripts were also present in the alimentary canal and uterus. At most of the sites of transgene expression the cell number (DNA content) was greatly increased, indicating a local action of the excess insulin-like growth factor II on cell multiplication. Adult total live weight was slightly increased and there was no macroscopic evidence of tumor formation. The characteristics of these transgenic mice indicate distinct local and systemic actions for insulin-like growth factor II.

The pharmacokinetics, tissue localization, and metabolic processing of recombinant human hepatocyte growth factor after intravenous administration in rats

Hepatocyte growth factor (HGF) is a pluripotent mitogen thought to be involved in liver regeneration. It is synthesized as a single chain promitogen and requires proteolytic processing to a two-chain heterodimeric form for biological activity. The pharmacokinetics and tissue distribution of radioiodinated single chain recombinant human HGF ([125I]rhuHGF) were studied in male Sprague-Dawley rats after an iv bolus dose. Pharmacokinetic parameters were determined from trichloroacetic acid-precipitable radioactivity in serum samples. There was a rapid distribution phase (t1/2 alpha = 3.1 min) and a slower elimination phase (t1/2 beta = 114 min). Tissue distribution was assessed by whole body autoradiography 5, 60, and 1440 min after an iv bolus dose. rhuHGF rapidly distributed to the liver, kidney, adrenal gland, and spleen. The importance of the liver in the rapid clearance and subsequent conversion of single chain pro-rhuHGF to the mitogenically active two-chain form was demonstrated using an isolated rat liver perfusion system. TCA-precipitable radioactivity excreted into the bile (1.0 +/- 0.1%) and released into the venous effluent (38.9 +/- 6.1%) was monitored for 60 min after a portal vein injection. The appearance of radioactivity in both the bile and venous effluent was maximal between 20-35 min. Further characterization of the reduced samples by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography revealed that the two-chain form of [125I]rhuHGF was the predominant form after hepatic perfusion. These studies suggest that the liver plays a major role in the rapid clearance and subsequent activation of pro-rhuHGF in vivo.

Pharmacokinetics and tissue distribution of recombinant human transforming growth factor beta 1 after topical and intravenous administration in male rats

Recombinant human transforming growth factor beta (rhTGF-beta 1) enhances the healing process after topical application to various animal wound models. A detailed pharmacokinetic and tissue distribution study was performed to support the clinical development of rhTGF-beta 1 for wound healing indications. Rats received radioiodinated or unlabeled rhTGF-beta 1 as an intravenous (iv) bolus or as a topical formulation applied to a full thickness wound. Plasma concentrations of TGF-beta 1 were estimated from TCA-precipitable radioactivity or were measured by ELISA. Following iv administration, the initial half-life was rapid (< 11 min), regardless of whether radiolabeled or unlabeled rhTGF-beta 1 was used. The terminal half-life was long (163 min) when the test material was radioiodinated and administered as a trace dose and relatively short (< or = 61 min) when given at high doses and assayed by ELISA. Analysis of plasma radioactivity by SDS-PAGE revealed a time-dependent clearance of the 25-kDa parent molecule without a significant appearance of lower molecular weight radiolabeled metabolites. The majority of the radioactivity was associated with highly perfused organs, known iodide elimination pathways, and the thyroid at 1 and 8 hr after iv injection. After topical administration of a high dose (0.8 mg/kg), no immunoreactive TGF-beta 1 was detectable in plasma samples taken over a 48-hr period. However, trace amounts (< or = 0.05 ng/mL) of acid-precipitable radioactivity were detected in plasma after topical application of [125I]rhTGF-beta 1 (1 microgram/kg, 126 microCi/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

In search of a big enough stick to tame the wild operating room inventory beast

This article discusses the many aspects of a prime vendor relationship with a medical-surgical distributor. It outlines features or value-added services that should be included when a hospital embarks on a new prime vendor relationship or tries to improve an existing one.