Levels of soluble cell adhesion molecules in patients with dyslipidemia

BACKGROUND

Increased expression of cell adhesion molecules (CAMs) on the vascular endothelium has been postulated to play an important role in atherogenesis. Both in vitro and in vivo studies have suggested that dyslipidemia may increase expression of CAMs.

METHODS AND RESULTS

To determine whether dyslipidemia is associated with increased expression of CAMs, we examined the levels of soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), and soluble E-selectin (sE-selectin) in individuals with either hypercholesterolemia or hypertriglyceridemia and in control subjects matched for age and sex. Patients with hypertriglyceridemia had significantly higher levels of sVCAM-1 (739 +/- 69 ng/mL) compared with patients with hypercholesterolemia (552 +/- 63 ng/mL) and control subjects (480 +/- 56 ng/mL). Levels of sICAM-1 were significantly increased in both the hypercholesterolemic and hypertriglyceridemic groups (298 +/- 29 and 342 +/- 31 ng/mL, respectively) compared with the control group (198 +/- 14 ng/mL). Levels of sE-selectin were significantly increased in hypercholesterolemic patients (74 +/- 9 ng/mL) compared with control subjects (48 +/- 5 ng/mL). Ten hypercholesterolemic patients were treated aggressively with atorvastatin alone or a combination of colestipol and either atorvastatin or simvastatin for a mean of 42 weeks and had an average LDL cholesterol reduction of 51%. Comparison of soluble CAMs before and after treatment showed a significant reduction only in sE-selectin (77 +/- 11 versus 56 +/- 6 ng/mL, P < or = .03) but not for sVCAM-1 or sICAM-1.

CONCLUSIONS

Although severe hyperlipidemia is associated with increased levels of soluble CAMs, aggressive lipid-lowering treatment had only limited effects on the levels. Increased levels of soluble CAMs in patients with hyperlipidemia may be a marker for atherosclerosis.

Vinylpyridine: an unusual cause of a chemical burn

A case of a chemical burn following cutaneous exposure to vinylpyridine is presented. This unusual injury was distinguished by the delay in onset of pain and erythema, followed by gradual resolution leaving patchy skin discolouration. The properties of vinylpyridine are outlined. This case illustrates the dangers of long-term chemical storage and the importance of proper disposal.

Decay in quality of closed-chest compressions over time

STUDY OBJECTIVE

To characterize fatigue-induced deterioration in the adequacy of closed-chest compressions performed over a period of 5 minutes and to determine whether CPR providers can recognize the effects of fatigue on compression adequacy.

DESIGN

Prospective evaluation of study subjects performing closed-chest compressions on an electronic mannequin that assesses compression placement and depth.

SETTING

Major resuscitation room in rural university hospital emergency department.

PARTICIPANTS

Eleven experienced nursing assistants who regularly provide CPR in the ED.

RESULTS

Each study participant performed 5 minutes of closed-chest compressions. Compression adequacy (for placement and depth) was assessed with the mannequin and reported on an attached monitor out of view of the study subjects. Subjects were asked to verbally indicate the point during their 5-minute compression period at which they felt too fatigued to provide effective compressions (arbitrarily defined as a minimum of 90% of all compressions being judged correct by the mannequin). We used one-way repeated-measures ANOVA and regression analysis to determine whether compression adequacy diminished over time. ANOVA was also used to determine whether the total compressions performed per minute diminished over time. The percentage of correct chest compressions decreased significantly after 1 minute of compressions (P = .0001). We found 92.9% of compressions performed during minute 1 to be correct. The percentages for minutes 2 through 5 were as follows: 67.1%, 39.2%, 31.2%, and 18.0%. Regression analysis revealed a decrement in compression adequacy of 18.6% per minute after the first minute of compressions. The number of total compressions attempted per minute did not decrease (P = .98). Study subjects did not accurately identify the point during their 5-minute sessions at which their fatigue caused compressions to become impaired. Whereas mean compression adequacy declined below 90% after only 1 minute, the time of indicated fatigue was 253 +/- 40 seconds (mean +/- SD).

CONCLUSION

Although compression rate was maintained over time, chest compression quality declined significantly over the study period. Because CPR providers could not recognize their inability to provide proper compressions, cardiac arrest team leaders should carefully monitor compression adequacy during CPR to assure maximally effective care for patients receiving CPR.

Lens epithelial cell apoptosis appears to be a common cellular basis for non-congenital cataract development in humans and animals

Cataract is a major ocular disease that causes blindness in many developing countries of the world. It is well established that various factors such as oxidative stress, UV, and other toxic agents can induce both in vivo and in vitro cataract formation. However, a common cellular basis for this induction has not been previously recognized. The present study of lens epithelial cell viability suggests such a general mechanism. When lens epithelial cells from a group of 20 cataract patients 12 to 94 years old were analyzed by terminal deoxynucleotidyl transferase (TdT) labeling and DNA fragmentation assays, it was found that all of these patients had apoptotic epithelial cells ranging from 4.4 to 41.8%. By contrast, in eight normal human lenses of comparable age, very few apoptotic epithelial cells were observed. We suggest that cataract patients may have deficient defense systems against factors such as oxidative stress and UV at the onset of the disease. Such stress can trigger lens epithelial cell apoptosis that then may initiate cataract development. To test this hypothesis, it is also demonstrated here that hydrogen peroxide at concentrations previously found in some cataract patients induces both lens epithelial cell apoptosis and cortical opacity. Moreover, the temporal and spatial distribution of induced apoptotic lens epithelial cells precedes development of lens opacification. These results suggest that lens epithelial cell apoptosis may be a common cellular basis for initiation of noncongenital cataract formation.

Symbiotic induction of a MADS-box gene during development of alfalfa root nodules

In response to infection by Rhizobium, highly differentiated organs called nodules form on legume roots. Within these organs, the symbiotic association between the host plant and bacteria is established. A putative plant transcription factor, NMH7, has been identified in alfalfa root nodules. nmh7 contains a MADS-box DNA-binding region and shows homology to flower homeotic genes. This gene is a member of a multigene family in alfalfa and was identified on the basis of nucleic acid homology to plant regulatory protein genes (MADS-box-containing genes) from Antirrhinum and Arabidopsis. RNA analysis and in situ hybridization showed that expression of this class of regulatory genes is limited to the infected cells of alfalfa root nodules and is likely to be involved in the signal transduction pathway initiated by the bacterial symbiont, Rhizobium meliloti. The expression of nmh7 in a root-derived organ is unusual for this class of regulatory genes.

Massive fungal contamination in animal care facilities traced to bedding supply

During the course of immunologic studies involving the gastrointestinal colonization of mice with Candida albicans, it became apparent that the animals were being exposed to large numbers of Aspergillus fumigatus spores which interfered with the C. albicans colonization. To determine the source of the A. fumigatus exposure and the extent of fungal contamination of the medical school vivarium and four satellite facilities, fungal analyses of feed, bedding, and air were undertaken. Initial samples from the air were collected with 3-h settle plates; air sampling following cleanup was done with an Anderson air sampler. The source of contamination in the mouse rooms was determined to be Beta Chip bedding, which came from the manufacturer highly contaminated. Beta Chip bedding (1 g) obtained from the manufacturer just prior to testing contained 10(4) CFU of A. fumigatus, 20 CFU of a zygomycete, and 10 CFU of a Penicillium sp. Coarse-grade Beta Chip had approximately one-half those levels of contamination. Pure Cob bedding was highly contaminated also, but with a Fusarium sp. and a Cladosporium sp. Untreated and heat-treated Sani-Chip as well as all other heat-treated preparations obtained from the manufacturer contained no detectable spores. Rodent chow direct from the manufacturer had no A. fumigatus, although it did contain 150 CFU of fungus per g, including 80 CFU of a Rhodotorula sp., 60 CFU of Cryptococcus uniguttulatus, and 1 CFU of a Penicillium sp.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of a nodule-enhanced glutamine synthetase from alfalfa: nucleotide sequence, in situ localization, and transcript analysis

We have characterized two glutamine synthetase (GS) cDNA clones (pGS13 and pGS100) representing mRNA from root nodules of alfalfa. pGS13 is a full-length version of a previously isolated partial cDNA from an alfalfa nodule cDNA library, while pGS100 was previously isolated from an alfalfa suspension culture cDNA library. Using the 3' untranslated region of the two cDNAs as gene-specific probes, we have shown that the GS genes represented by pGS100 and pGS13 are expressed in all organs tested, although at varying levels. pGS13, however, represents the nodule-enhanced GS gene class. Genomic Southern blot analysis using gene-specific probes shows multiple hybridizing bands, in each case suggesting multiple genes and/or alleles for each class of cytoplasmic GS genes. In situ hybridization of alfalfa nodule sections with gene-specific antisense RNA probes has shown that the nodule-enhanced GS genes are induced in the invasion zone and that their expression is limited to the symbiotic zone, while the GS genes represented by pGS100 are induced in the early symbiotic zone and are expressed throughout the symbiotic and senescent zones. Transcripts for both sets of GS genes are localized in the infected cells and based on the spatial expression pattern it would appear that the two gene classes are induced independently of the onset of nitrogen fixation.

Managing ulceration of the breast

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Preparing a clinical activities database in plastic surgery using existing information systems

The collection of data for audit and clinical activity analysis is time consuming. This report outlines a technique by which data held on hospital data systems, such as the PAS and theatre management systems, can be made available to clinical investigators. The saving in time and effort can be enormous.

A quantitative method for measuring library user journal needs: a pilot study using CD plus MEDLINE usage statistics

OBJECTIVE

To develop a quantitative method for measuring library user journal needs based on an analysis of bibliographic search results.

DESIGN

Retrospective bibliometric comparison of citation selections generated by users in the library.

MEASURES

Number of times each journal was identified by library users during multiple bibliographic search sessions.

RESULTS

Library users identified 4907 journal titles. The top 200 journal titles accounted for 55% of the library user journal needs. Of the 1380 unique titles identified, 652 were selected once.

CONCLUSION

Our pilot study demonstrated that analysis of bibliographic search results can be used to identify library user journal needs. Such a method could also be used to estimate user requirements for online, full-text scientific journals.

Novice and expert head nurses: a comparative study of work activities and behaviours

The head nurse represents a key management position in hospital organizations. This descriptive study examines the role of the head nurse and identifies differences that exist between newly appointed head nurses and experts in the position. Questionnaire, interview and nonparticipant observation methods were used to collect and analyze data. Recommendations for educational preparation, selection criteria and recruitment and retention strategies are made based upon the study results.

Montreal MD's AIDS-related collapse raises disclosure issue at McGill teaching hospitals

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Passive smoking and canine lung cancer risk

A case-control study was conducted to determine whether household exposure to environmental tobacco smoke is associated with an increased risk for lung cancer in pet dogs. Lung cancer cases and controls with other forms of cancer were obtained from two veterinary teaching hospitals during 1985-1987. Exposures assessed included the number of smokers in the household, the amount smoked, and the proportion of time spent indoors by the pet. A weak relation was found for exposure to a smoker in the home (odds ratio = 1.6, 95% confidence interval 0.7-3.7), after controlling for confounding in stratified analyses. Strong evidence for a further increase in risk associated with more than one smoker in the home was not found, nor was a significant trend observed for increasing number of packs of cigarettes smoked per day or an exposure index based on number of smokers in each household, packs smoked per day, and the proportion of time the dog spent within the home. However, skull shape appeared to exert effect modification; the risk was restricted to breeds with short and medium length noses (odds ratio = 2.4, 95% confidence interval 0.7-7.8). Despite the inconclusive findings of the current study, epidemiologic studies in pet animals may add to our understanding of environmental tobacco smoke effects in human populations.

Ten weeks of intermittent hypocalcemic stimulation does not produce functional parathyroid hyperplasia

Hypocalcemia is a major stimulus for parathyroid hormone secretion and presumably the major cause of parathyroid hyperplasia in chronic hypocalcemic syndromes. We could find no data to indicate what degree, duration, or frequency of hypocalcemia is needed to produce parathyroid hyperplasia in humans. We have monitored the effects of thrice weekly hypocalcemic parathyroid stimulation for 10 weeks. Measurements were made during a study designed to test the feasibility of carrying out a randomized, blinded trial of "chelation therapy," a widely used but unproven method to treat atherosclerotic symptoms. Eight patients received infusions of disodium ethylenediaminetetraacetic acid (EDTA) and six received placebo infusions thrice weekly for ten weeks. The EDTA infusions (50 mg/kg over three hours) lowered serum ionized calcium at two hours by an average of 0.20 mmol/L and trebled the immunoreactive parathyroid hormone (iPTH) value. Basal serum iPTH, ionized calcium and 1,25-dihydroxyvitamin D values, measured just before the infusion, did not change significantly after 10 weeks of treatment with either EDTA or placebo. The increment in serum iPTH produced by the EDTA-induced hypocalcemia was also unchanged. Lowering ionized serum calcium to values below the normal range three times a week for 10 weeks is not a sufficient stimulus to cause a detectable increase in basal or stimulated parathyroid function.

Dose-finding study of intramuscular midazolam preanesthetic medication in the elderly

Intramuscular midazolam frequently results in excessive sedation in elderly patients. The effects of preanesthetic medication with intramuscular midazolam were examined in 100 elderly patients, aged 60-86 yr, given 1, 2, or 3 mg midazolam or placebo using a randomized, double-blind study design. Level of sedation and anxiety were assessed every 15 min for 1 h. Picture cards were presented at the same times in order to assess recall of these cards 24 h later. All three doses of midazolam produced rapid onset of sedation, anxiolysis, and anterograde amnesia. These effects decreased in intensity by 60 min after drug injection. The intensity and extent of these effects were comparable with those reported with higher doses in younger patients, although with the 1-mg midazolam dose the effects were shorter-lived, and a difference from placebo was not consistently seen. Three patients (3%), all older than 70 yr, became unresponsive to vocal and tactile stimuli. This level of drowsiness was unrelated to body weight, age, or ASA physical status. We conclude that in adults between 60-69 yr old, midazolam 2 or 3 mg intramuscularly can be effective as preanesthetic medication without causing excessive drowsiness. However, intramuscular midazolam should be used cautiously, under continuous observation, in patients aged 70 yr and older because excessive drowsiness may occur.