Airway management of patients with tracheobronchial stents

The use of tracheobronchial stents for compromised large airways is increasing. We provide a case series highlighting some of the complications of airway management in patients with tracheobronchial stents in situ and propose an approach for dealing with this potentially complicated situation.

The utilisation of intraosseous infusion in the resuscitation of paediatric major trauma patients

Intraosseous lines are a reliable and rapid tool for obtaining vascular access in emergency situations, particularly in children. Their use is recommended when intravenous access cannot be easily secured and there is a need for fluid or pharmacological resuscitation. Training in this technique is included in the Advanced Trauma Life Support (ATLS) and Advanced Paediatric Life Support course (APLS) provider courses. The objective of this study is to analyse the national use of intraosseous lines in paediatric trauma in England and Wales. Data has been collected from the Trauma Audit and Research Network (TARN) group longitudinally over 14 years from 1988 to 2002. From 23,489 paediatric trauma cases, intraosseous lines were used in only 129 patients. Compared with the remainder of the paediatric data, we found that these were the younger (1-6 years), more severely injured patients (higher ISS, lower GCS, higher head, thorax, and abdominal AIS). The mortality of these patients was high at 64% compared with 4% overall. IO line use was greater in general than in Paediatric hospitals, perhaps due to good intravenous access skills in paediatric centres. We recommend that intraosseous line use should be a skill available to everybody involved in paediatric trauma resuscitation, particularly those who may not have refined paediatric intravenous cannulation skills.

Children followed with difficulty: how do they differ?

OBJECTIVE

To determine if very low birthweight children followed with ease differ in any perinatal or sociodemographic characteristics, or outcomes, compared with children followed with more difficulty.

METHODOLOGY

Consecutive children of birthweight < 1000 g or with gestational ages < 28 weeks born in 1991 (n = 51) or of birthweight < 1500 g born in 1992 (n = 166) at the Royal Women's Hospital, Melbourne, surviving to 5 years of age, were assessed at 5 years of age, corrected for prematurity. Those who attended on the first mutually agreed appointment without substantial reluctance were considered to have been followed with ease. The remainder were considered to have been followed with difficulty. Outcomes included impairments such as cerebral palsy, blindness, deafness, and low IQ. Children had a disability if they had any of cerebral palsy, blindness, deafness requiring amplification, or an IQ more than 1 SD below the mean.

RESULTS

Of the 217 survivors, 204 (94%) were assessed fully at 5 years of age. Of the 204 children assessed, 153 (75%) were followed with ease, and 51 (25%) with difficulty. Of data available in the perinatal period, significantly fewer children followed with more difficulty came from intact families, and more of their mothers had fewer than 12 years of schooling. More children followed with difficulty had a disability (41% compared with 19%), as they predominantly had lower IQ scores (mean difference in IQ - 12.7, 95% confidence interval - 18.0, - 7.4). The association between difficulty of assessment and both higher rates of disability and lower IQ scores remained after adjustment for significant perinatal and sociodemographic variables.

CONCLUSIONS

Children followed with difficulty can partly be recognized on several sociodemographic characteristics in the perinatal period, and have substantially worse sensorineural outcomes than those followed with ease. In any longitudinal study, the more incomplete the follow up, the lower will be the rate of adverse sensorineural outcome.

Maximizing the use of a Web-based teaching skills curriculum for community-based volunteer faculty

BACKGROUND

The University of Kansas School of Medicine in Wichita created an Internet-based faculty development curriculum for community-based faculty. Because relatively few physicians use Internet-based continuing medical education (CME), the most cost-effective methods of encouraging use need to be identified.

METHOD

Five interventions intended to increase use of the curriculum were assessed. The number of times the CME curriculum Webpages were accessed was correlated with the interventions.

RESULTS

Demonstrating the Website to faculty at a semiannual meeting elicited the most Website "hits." Electronic mail and flyers also appeared to be effective in stimulating interest in the Website. Only four community-based faculty applied for CME credit for completing the curricular modules.

FINDINGS

Multiple modalities should be used in advertising and stimulating interest in an Internet-based faculty development curriculum. Demonstrating the Website to faculty at a meeting appeared to achieve the greatest return. Offering CME credit was not helpful in stimulating interest.

Molecular and pharmacological aspects of antiestrogen resistance

Endocrine therapy is effective in approximately one-third of all breast cancers and up to 80% of tumors that express both estrogen and progesterone receptors. Despite the low toxicity, good overall response rates, and additional benefits associated with its partial agonist activity, most Tamoxifen-responsive breast cancers acquire resistance. The development of new antiestrogens, both steroidal and non-steroidal, provides the opportunity for the development of non-cross-resistant therapies and the identification of additional mechanisms of action and resistance. Drug-specific pharmacologic mechanisms may confer a resistance phenotype, reflecting the complexities of both tumor biology/pharmacology and the molecular endocrinology of steroid hormone action. However, since all antiestrogens will be effective only in cells that express estrogen receptors (ER), many mechanisms will likely be directly related to ER expression and signaling. For example, loss of ER expression/function is likely to confer a cross-resistance phenotype across all structural classes of antiestrogens. Altered expression of ERalpha and ERbeta, and/or signaling from transcription complexes driven by these receptors, may produce drug-specific resistance phenotypes. We have begun to study the possible changes in gene expression that may occur as cells acquire resistance to steroidal and non-steroidal antiestrogens. Our preliminary studies implicate the altered expression of several estrogen-regulated genes. However, resistance to antiestrogens is likely to be a multigene phenomenon, involving a network of interrelated signaling pathways. The way in which this network is adapted by cells may vary among tumors, consistent with the existence of a highly plastic and adaptable genotype within breast cancer cells.

Improved mucosal protection against Venezuelan equine encephalitis virus is induced by the molecularly defined, live-attenuated V3526 vaccine candidate

The genetically engineered, live-attenuated Venezuelan equine encephalitis (VEE) virus vaccine candidate, V3526, was evaluated as a replacement for the TC-83 virus vaccine. Protection from lethal subcutaneous or aerosol challenge was evaluated in vaccinated mice clinically and immunohistochemically. Subcutaneous administration of V3526 induced systemic and mucosal protection more efficiently than did the TC-83 vaccine. The bronchial IgA responses induced in mice by subcutaneous administration of vaccines significantly corresponded to the ability to survive aerosol challenge with virulent virus. Furthermore, V3526 delivered by aerosol induced more complete mucosal protection than either vaccine administered subcutaneously. The ability of V3526 to induce protection in mice warrants its consideration for further testing as a potential vaccine candidate for human use.

Evidence for a zinc/proton antiporter in rat brain

The data presented in this paper are consistent with the existence of a plasma membrane zinc/proton antiport activity in rat brain. Experiments were performed using purified plasma membrane vesicles isolated from whole rat brain. Incubating vesicles in the presence of various concentrations of 65Zn2+ resulted in a rapid accumulation of 65Zn2+. Hill plot analysis demonstrated a lack of cooperativity in zinc activation of 65Zn2+ uptake. Zinc uptake was inhibited in the presence of 1 mM Ni2+, Cd2+, or CO2+. Calcium (1 mM) was less effective at inhibiting 65Zn2+ uptake and Mg2+ and Mn2+ had no effect. The initial rate of vesicular 65Zn2+ uptake was inhibited by increasing extravesicular H+ concentration. Vesicles preloaded with 65Zn2+ could be induced to release 65Zn2+ by increasing extravesicular H+ or addition of 1 mM nonradioactive Zn2+. Hill plot analysis showed a lack of cooperativity in H+ activation of 65Zn2+ release. Based on the Hill analyses, the stoichiometry of transport may include Zn2+/Zn2+ exchange and Zn2+/H+ antiport, the latter being potentially electrogenic. Zinc/proton antiport may be an important mode of zinc uptake into neurons and contribute to the reuptake of zinc to replenish presynaptic vesicle stores after stimulation.

Zinc transport in the brain: routes of zinc influx and efflux in neurons

Studies of the routes of entry and exit for zinc in different tissues and cell types have shown that zinc can use several pathways of exit or entry. In neurons, known pathways include (1) presynaptic release along with glutamate when synaptic vesicles empty their contents into the synaptic cleft, (2) voltage-gated L-type Ca(2+) channels and glutamate-gated channels that provide an entry route when cells are depolarized and that mediate extracellular zinc toxicity and (3) a plasma membrane transporter potentially present in all neurons important for cellular zinc homeostasis. The least understood of these pathways, in terms of mechanism, is the transporter pathway. The kinetics of zinc uptake in cultured neurons under resting conditions are consistent with and suggest the existence of a saturable transporter in the plasma membrane. The proteins responsible for plasma membrane zinc transport have not yet been definitely identified. Likely candidates include two proteins identified by molecular cloning termed zinc transporter 1 and divalent cation transporter DCT1. Both proteins have been shown to be expressed in the brain, but only DCT1 is clearly demonstrated to be a transport protein, whereas zinc transporter 1 may only modulate zinc transport in association with as-yet-unidentified proteins. Understanding the mechanism and neuromodulation of plasma membrane zinc transport will be an important first step toward a complete understanding of neuronal zinc homeostasis.

The prevalence and expression of inherited connexin 26 mutations associated with nonsyndromic hearing loss in the Israeli population

Connexin 26 (GJB2) mutations lead to hearing loss in a significant proportion of all populations studied so far, despite the fact that at least 50 other genes are also associated with hearing loss. The entire coding region of connexin 26 was sequenced in 75 hearing impaired children and adults in Israel in order to determine the percentage of hearing loss attributed to connexin 26 and the types of mutations in this population. Age of onset in the screened population was both prelingual and postlingual, with hearing loss ranging from moderate to profound. Almost 39% of all persons tested harbored GJB2 mutations, the majority of which were 35delG and 167delT mutations. A novel mutation, involving both a deletion and insertion, 51del12insA, was identified in a family originating from Uzbekistan. Several parameters were examined to establish whether genotype-phenotype correlations exist, including age of onset, severity of hearing loss and audiological characteristics, including pure-tone audiometry, tympanometry, auditory brainstem response (ABR), and transient evoked otoacoustic emissions (TEOAE). All GJB2 mutations were associated with prelingual hearing loss, though severity ranged from moderate to profound, with variability even among hearing impaired siblings. We have not found a significant difference in hearing levels between individuals with 35delG and 167delT mutations. Our results suggest that, in Israel, clinicians should first screen for the common 167delT and 35delG mutations by simple and inexpensive restriction enzyme analysis, although if these are not found, sequencing should be done to rule out additional mutations due to the ethnic diversity in this region.

Intraoperative bacterial contamination in operations for joint replacement

All surgical operations have the potential for contamination, and the equipment used can harbour bacteria. We collected samples from 100 elective primary hip and knee arthroplasties. These showed rates of contamination of 11.4% for the sucker tips, 14.5% for light handles, 9.4% for skin blades and 3.2% for the inside blades used during surgery; 28.7% of gloves used for preparation were also contaminated. Of the samples taken from the collection bags used during hip arthroplasty, 20% grew bacteria, which represents a significant microbial reservoir. Also, 17% of theatre gowns were contaminated at the end of the operation. Contamination was found in 10% of the needles used during closure of the fascia. Overall, 76% of the organisms grown were coagulase-negative staphylococcus. A total of 63% of operations showed contamination in the field of operation. Some changes in practice are suggested. Follow-up for a minimum of two years revealed one deep infection but the organism was not identified as a contaminant. These data provide a baseline for studying the bacteriology of the surgery of revision arthroplasty.

Intraoperative bacterial contamination in operations for joint replacement

All surgical operations have the potential for contamination, and the equipment used can harbour bacteria. We collected samples from 100 elective primary hip and knee arthroplasties. These showed rates of contamination of 11.4% for the sucker tips, 14.5% for light handles, 9.4% for skin blades and 3.2% for the inside blades used during surgery; 28.7% of gloves used for preparation were also contaminated. Of the samples taken from the collection bags used during hip arthroplasty, 20% grew bacteria, which represents a significant microbial reservoir. Also, 17% of theatre gowns were contaminated at the end of the operation. Contamination was found in 10% of the needles used during closure of the fascia. Overall, 76% of the organisms grown were coagulase-negative staphylococcus. A total of 63% of operations showed contamination in the field of operation. Some changes in practice are suggested. Follow-up for a minimum of two years revealed one deep infection but the organism was not identified as a contaminant. These data provide a baseline for studying the bacteriology of the surgery of revision arthroplasty.

Chamber-specific cardiac expression of Tbx5 and heart defects in Holt-Oram syndrome

To further define the role of a T-box transcription factor, Tbx5, in cardiac development, we have examined its expression in the developing mouse and chick heart and correlated this pattern with cardiac defects caused by human TBX5 mutations in Holt-Oram syndrome. Early in the developing heart, Tbx5 is uniformly expressed throughout the entire cardiac crescent. Upon formation of the linear heart tube, Tbx5 is expressed in a graded fashion, stronger near the posterior end and weaker at the anterior end. As the heart tube loops, asymmetric Tbx5 expression continues; Tbx5 is expressed in the presumptive left ventricle, but not the right ventricle or outflow tract. This pattern of expression is maintained in more mature hearts. Expression in the ventricular septum is restricted to the left side and is contiguous with left ventricular free wall expression. Trabeculae, vena cavae (inferior and superior), and the atrial aspect of the atrioventricular valves also express high levels of Tbx5. These patterns of Tbx5 expression provide an embryologic basis for the prevalence of atrial septal defects (ostium primum and secundum), ventricular muscular septal defects, and left-sided malformations (endocardial cushion defects, hypoplastic left heart, and aberrant trabeculation) observed in patients with Holt-Oram syndrome.

Rapidly growing squamous cell carcinoma

BACKGROUND

Squamous cell carcinoma (SCC) may present with a history of rapid growth. Although multiple subtypes have been described regarding histologic characteristics and etiology, the subset of rapidly growing squamous cell carcinomas (RGSCC) has not been described.

OBJECTIVE

To evaluate and describe the clinical and histologic characteristics of squamous cell carcinomas that grow rapidly.

METHODS

Recorded clinical data and biopsies of 26 lesions with a history of rapid growth and histologically diagnosed as SCC were reviewed.

RESULTS

Rapidly growing SCC occurred most commonly on the head and neck, followed by hands and extremities, and had an average duration of 7 weeks before diagnosis. The average size of the lesions was 1.29 cm and nearly 20% occurred in immunosuppressed patients.

CONCLUSIONS

Some SCCs may grow rapidly. The reason for the rapid growth is not clear and several hypotheses are discussed including immunosuppression and viral etiology. These lesions should be treated aggressively as their behaviour and prognosis are not yet well described.

Origins of the extracellular glutamate released during total metabolic blockade in the immature retina

Previous studies have shown that complete blockade of metabolism in embryonic chick retina causes a time-dependent increase in the release of glutamate into the extracellular space. The present study examined the cellular source of this glutamate, i.e., neuronal and/or glial. Pure cultures of retinal neurons or glia were labeled for 10 min at 37 degrees C with [3H]acetate. Retinal glia, but not retinal neurons, were found to selectively and preferentially metabolize acetate, thus producing 3H-labeled amino acids in the glial compartment. This finding provides direct evidence to substantiate findings from several other laboratories that have indirectly determined the preferential metabolism of acetate by glia by using mixed neuronal/glial populations. To study the cellular source of glutamate released during total metabolic blockade, whole retina were prelabeled with [3H]acetate plus [U-14C]glucose (to label the neuronal compartment). Total metabolic blockade was instituted with a combination of iodoacetate (IOA) plus KCN, and the release of glutamate into the medium was followed at 5, 15, and 30 min. During total energy blockade, net extracellular glutamate was not elevated at 5 min [0.17 +/- 0.02 vs. 0.12 +/- 0.01 microM for treated vs. control retina (means +/- SEM), respectively], but was increased significantly at 15 (1.2 +/- 0.26 microM) and 30 min (2.6 +/- 0.22 microM). Total [3H]glutamate in the medium during IOA/KCN treatment was unchanged at 5 min, but was increased 1.5- and threefold above basal levels at 15 and 30 min, respectively. During the time when extracellular glutamate increased, the specific activity of [3H]glutamate remained fairly constant, 731 +/- 134 and 517 +/- 82 dpm/nmol (means +/- SEM) at 15 and 30 min, respectively. In contrast, 14C-labeled glutamate in the medium did not increase during IOA/KCN treatment and paralleled basal levels. Thus, the specific activity of 14C-labeled extracellular glutamate decreased from 309 +/- 87 dpm/nmol at 15 min to 42 +/- 8 dpm/nmol at 30 min. Prior loading of the tissue with 0.5 mM trans-pyrrolidine-2,4-dicarboxylate (t-PDC), a glutamate transport inhibitor, blocked 57% of the glutamate released at 30 min of IOA/KCN exposure, suggesting that reversal of an Na+-dependent glutamate transporter was a key contributor to the appearance of extracellular glutamate during energy deprivation. The increase in extracellular [3H]glutamate, constancy of the specific activity of extracellular [3H]glutamate, decrease in the specific activity of extracellular [14C]glutamate, and attenuation of release by prior loading with t-PDC indicate that glial pools of glutamate released via reversal of the transporter contribute significantly to the rise in extracellular glutamate after metabolic inhibition in this preparation.

Core biopsy for microcalcifications in the breast

BACKGROUND

The conventional method of dealing with clustered mammographic microcalcification in the breast when it is of uncertain aetiology is to undertake either a short-term mammographic review or to surgically excise the abnormal area and submit it for histological examination. Stereotactic wide-bore needle biopsy (core biopsy) of microcalcifications is a suitable alternative to surgical biopsy and experience with this technique forms the basis of the present study.

METHODS

Percutaneous core biopsy has been used at the Wesley Breast Clinic as a means of assessing clustered calcification in 297 cases from November 1992 to October 1995. The procedure is done under local anaesthesia as an outpatient procedure using a stereotactic attachment to a standard mammography unit.

RESULTS

A diagnosis of frank malignancy was made on core samples in 22 cases (7.4%), and in all of these malignancy was confirmed at open surgical biopsy. In a further six women in whom the core biopsy was reported as 'suspicious of malignancy', open surgical biopsy confirmed malignancy in three women, lobular in situ carcinoma was found in two women, and atypical ductal hyperplasia in one woman. In two instances the core sample was reported as showing atypical ductal hyperplasia and in those cases, this was confirmed at open surgical biopsy. In 265 cases (89%) the histology of the core revealed appearances of benign breast tissue. Open surgical biopsy has been undertaken in only six of these cases, but in all instances the histology has confirmed a benign process. In the two remaining cases, the procedure was considered to be technically unsatisfactory, and open surgical biopsy was recommended because of doubt about the appearance of the microcalcification. In both instances, malignancy was demonstrated.

CONCLUSIONS

Core biopsy of clustered mammographic microcalcification of uncertain aetiology is recommended as a satisfactory and reliable alternative to open surgical biopsy. It is less expensive, can be done quickly, produces few complications, and does not produce subsequent mammographic distortion.

Genistein inhibits Na+/Ca2+ exchange activity in primary rat cortical neuron culture

We have examined the possible regulatory effect of tyrosine kinase activity on Ca2+ transport observed in the cultured rat cortical neurons. Na+/Ca2+ exchange was studied using cells cultured for various time periods. A nearly two fold increase in Ca2+ uptake was seen when comparing 3 day and 9 day cultures. Western blot analysis also showed a two fold increase in Na+/Ca2+ exchanger (NCX1) protein levels as cells matured in culture. To study the effect of genistein (a specific tyrosine kinase inhibitor) cells were incubated with 100 microM genistein (in 1% DMSO) for 1 hour before the assay of Na+/Ca2+ exchange activity. There was a significant decrease of Ca2+ uptake in genistein treated neurons (control: 4.596+/-0.205 nmol/mg protein/15 min, n=12; genistein: 1.420+/-0.131 nmol/mg protein/15 min, n=12, mean+/-S.E. P<0.001). Daidzein, an inactive analog of genistein and phorbol myristate acetate (PMA), a PKC activator were without effect. The results suggest that as cells mature in culture, Na+/Ca2+ exchange capacity increases, as a result of greater protein expression. Exposure to genistein inhibited Ca2+ uptake suggesting that the exchanger may be modulated by tyrosine phosphorylation.

Aging does not affect steady-state expression of the Na+/Ca2+ exchanger in rat brain

1. Steady-state protein and mRNA levels of the Na+/Ca2+ exchanger were studied in old (24-month) and young (3-month) brains of male Fischer 344 rats by Western and Northern analysis. 2. Northern analysis with a cDNA proble for the Na+/Ca2+ exchanger amplified from human brain RNA indicated the presence of two transcripts for the Na+/Ca2+ exchanger (6 and 16 kb). Both transcripts were present in similar abundance in the cerebrum and hippocampus. In the cerebellum the 6-kb transcript predominated. The cerebellum had the highest overall level of expression. There were no significant age-related effects seen on the level of expression of either transcript in each of the brain areas tested. 3. Western analysis of plasma membrane vesicles purified from cerebral cortex identified a single protein of 116 kDa. Consistent with the Northern analysis, no age-related effect on protein levels was seen. 4. The mechanisms underlying altered Na+/Ca2+ exchange activity in aging rat brain (Michaelis, 1989) most likely do not involve changes in gene expression and are therefore more likely to represent posttranslation modifications of the protein.

Post-transcriptional regulation of the Na+/Ca2+ exchanger in aging rat heart

Altered calcium homeostasis in the senescent heart appears to be the result, at least in part, of decreased Na+/Ca2+ exchange activity. To further investigate the basis of the decrease in Na+/Ca2+ exchange activity, Na+/Ca2+ exchanger gene expression in the heart was compared in 3 and 24 month old male Fischer 344 rats. Sarcolemmal vesicles prepared from left ventricle and septum showed reduced Na(+)-dependent Ca2+ uptake in 24 month old animals when compared to 3 month old animals (0.156 +/- 0.005 and 0.135 +/- 0.008 nmol Ca2+/mg/10 s; mean +/- S.E. for 3 month and 24 month old animals, respectively). Western analysis showed immunodetectable Na+/Ca2+ exchanger protein levels were decreased by 19% in 24 month old animals when compared to 3 month old animals. Poly(A+) RNA was purified from left and right ventricle and left and right atria and subjected to Northern analysis using digoxin labeled cDNA probes for the Na+/Ca2+ exchanger and actin. The Na+/Ca2+ exchanger probe labeled a 7 kb message in both ventricle and atria, while the actin probe labeled both beta-actin (2.2 kb) and alpha-actin (1.4 kb). The steady state level of expression of Na+/Ca2+ exchanger Poly(A+) RNA when normalized to beta-actin, was similar when ventricle and atria were compared. There were no observable differences in Na+/Ca2+ exchanger or alpha-actin Poly(A+) RNA steady state levels when comparing 3 and 24 month old animals. The results suggest that reduced Na+/Ca2+ exchange activity in the left ventricle of 24 month old animals was most likely the result of post-transcriptional modification of the protein that was detectable by Western analysis.

Studies of the mechanism underlying increased Na+/Ca2+ exchange activity in Alzheimer's disease brain

The Na+/Ca2+ exchanger was characterized in plasma membrane vesicles derived from frozen human postmortem tissues. The frontal cortex, temporal cortex and cerebellum of control and Alzheimer's disease (AD) tissues were compared. Na+/Ca2+ exchange activity was defined as the change in vesicular Ca2+ content seen after Na+ loaded vesicles were diluted into choline buffer. The time course of changes in Ca2+ content after dilution was similar in all three regions of control brain. In AD brain, both frontal and temporal cortex vesicles showed elevated Ca2+ content, most evident as an increased peak Ca2+ content at 2 min. The AD cerebellar cortex time course was similar to control and did not show an elevated peak at 2 min. No differences were seen in the passive permeability to Ca2+ when comparing plasma membrane vesicles prepared from control and AD brain. Vesicles from the frontal and temporal cortex of AD brain showed increases in the Vmax of the initial velocity of Ca2+ uptake when compared to control brain, whereas, the cerebellum did not. There were no significant effects of AD on the Km for Ca2+ activation of the initial velocity. Ca2+ influx measured during the rise in vesicular Ca2+ content was elevated in vesicles from AD temporal cortex when compared to control. Two known inhibitors (exchange inhibitory peptide and dichlorobenzamil) of the cardiac Na+/Ca2+ exchanger inhibited the human brain exchanger equally well in control and AD vesicles. Increased Na+/Ca2+ exchange activity was not due to astrocytic gliosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Outcome of deliberate self-poisoning. An examination of risk factors for repetition

BACKGROUND

One of the most important outcomes following an episode of non-fatal deliberate self-poisoning is its repetition.

METHOD

In a prospective follow-up study the subjects were 992 people responsible for 1096 consecutive episodes of deliberate self-poisoning recorded at a teaching hospital accident and emergency department. Risk factors examined were socio-demographic variables, psychiatric and self-harm history, aspects of the self-poisoning episode, and appearance and behaviour at accident and emergency; the frequency of each was compared between those patients who repeated within one year (n = 116) and those who did not (n = 876).

RESULTS

Those who repeated were more likely to have ingested more than one drug, to report a previous episode of self-poisoning, to be aged 25-54, and to have experienced previous psychiatric care or psychiatric admission. They were less likely to be in paid employment, or to have expressed a threat to another person or written a note. The best predictor--previous psychiatric contact--only had a positive predictive value of 21% (95% confidence interval 16-25%).

CONCLUSIONS

Risk factors for repetition of self-poisoning should be kept up-to-date despite modest predictive power. More attention might be paid to clinical rather than socio-demographic aspects of self-harm.

Evaluating a patient satisfaction survey for maximum benefit

BACKGROUND

Patient satisfaction surveys are now in use in some form at most hospitals and health care systems. Yet, it is unclear how well information collected meets the needs of all groups who might benefit from patient feedback. An evaluation was conducted at the Center for Outcomes Research, Sisters of Providence Health System (Portland, Ore), to determine the extent to which the survey, then almost three years in use, was satisfying its internal consumers and to guide redesign of the entire survey process.

METHOD

The evaluation of the survey process was designed to address several questions: who uses the results (consumers); what are their objectives (goals); what results are useful (product); and what is done with the results (intervention utility). Techniques such as interviews, literature reviews, and supplemental data collection, were used to explore the needs of each consumer group.

CONCLUSION

The evaluation has led to a number of changes in the patient satisfaction survey process. Large-scale patient satisfaction surveys result in large-scale costs and therefore must be beneficial to multiple users in multiple ways.

Effects of a job-simulated exercise programme on employees performing manual handling operations

This study investigated the effects of physical training on employees performing manual handling operations in three manufacturing plants. Employees from two plants were trained using progressive resistance exercise (PRE) while employees in the third plant were trained using PRE and trunk flexibility exercises (TFE). The results were: (1) a combined TFE and PRE programme significantly improved muscular endurance (124%), dynamic (86%) and static (back: 59%; arm: 25%; shoulder: 23%) muscular strength, and trunk flexibility (low back flexibility: 11%; total trunk rotation: 48%); (2) a dynamic PRE programme did not improve static strength (arm: 3%; shoulder: 8%; back: 14%; composite: 7%) as much as dynamic strength (71%); (3) endurance time at a fixed workload increased without changing job demand perception, but daily operations were performed more easily.

Evidence for functional dissociation of dependence and tolerance in guinea-pig isolated ileal segments following 20 hour exposure to morphine in vitro

1. In the present study we have examined the relationship between tolerance and dependence in isolated ileal segments from the guinea-pig under three different conditions: fresh preparations not previously exposed to morphine (fresh/morphine naive); preparations stored overnight at 4 degrees C in modified Krebs-Henseleit saline (overnight-stored/morphine-naive); preparations stored overnight at 4 degrees C in Krebs-Henseleit saline containing 10 microM morphine and extensively washed with modified Krebs-Henseleit saline to remove residual morphine (overnight-stored/morphine-exposed). 2. Morphine produced a concentration-dependent inhibition of the response of ileal segment to 0.1 Hz, 1 ms and 10 V transmural field stimulation in fresh/morphine-naive, overnight-stored/morphine-naive and overnight-stored/morphine-exposed preparations. The maximum effect observed was similar in all three preparations-approximately 80% inhibition. Although, morphine was significantly more potent in the fresh/morphine-naive preparations (pD2 6.72 +/- 0.05, n = 8) than either the overnight-stored/morphine-native (pD2 6.42 +/- 0.11, n = 8) or the overnight-stored/morphine-exposed (pD2 6.44 +/- 0.14, n = 8), there was no significant difference between the overnight exposure to ileal segments to 10 microM morphine at 4 degrees C failed to induce tolerance to morphine. 3. The mu opiate receptor antagonist, naloxone (10 microM), produced contractions in both fresh/morphine-naive and overnight-stored/morphine-naive ileal segments following acute exposure to 10 microM morphine. Naloxone (10 microM) also produced contractions in 2/9 fresh/morphine-naive, 1/9 overnight-stored/morphine-naive and 7/9 overnight-stored/morphine-exposed preparations in the absence of morphine. The greater incidence of naloxone-induced contractions in overnight-stored/morphine-exposed preparations,suggests that dependence in this model is the product of adaptive changes that outlive the presence of morphine.4. The selective alpha2-adrenoceptor agonists, clonidine (0.3 microM) and 5-bromo-6-[2-imidazolin-2-ylamino]-quinoxaline bitartrate (UK-14304, 1 microM), inhibited naloxone-induced contractions in overnight-stored/morphine-exposed preparations of ileal segments (n = 4 preparations for each agonist), suggesting that the response is due to transmitter release from the myenteric plexus.5. The findings in the present study indicate that tolerance and dependence to morphine in ileal segments of the guinea-pig can be functionally dissociated by overnight exposure to morphine at 4 degrees C.The development of tolerance to morphine, unlike dependence, appears to be a temperature-dependent process. This also raises the possibility that naloxone possesses intrinsic negative agonism at morphine sensitive receptors, which is manifested as a functional response only after adaptive changes in the myenteric plexus following exposure to morphine.

Analysis of Na+/Ca2+ exchange activity in human brain: the effect of normal aging

Na+/Ca2+ exchange activity and passive permeability to Ca2+ were analyzed in plasma membrane vesicles (PMV) purified from whole rat brain and three regions of human brain: frontal cortex, temporal cortex, and cerebellum. Accumulation of Ca2+ due to Na+/Ca2+ exchange activity showed a characteristic pattern of an initial rapid rise in Ca2+ content followed by a stable plateau in both rat and human brain. Total Ca2+ accumulation in rat brain PMV was on average three-fold higher than in human brain. Passive permeability to Ca2+ was measured as the rate of Ca2+ release from PMV first loaded with 45Ca by Na+/Ca2+ exchange and then exposed to 1 mM EGTA. The Ca2+ permeabilities of human and rat brain PMV were similar. Ca2+ release from rat brain PMV was faster overall and was resolved into fast and slow components while in human brain a single slow component was found. Post mortem delay up to 4 h had no effect on Na+/Ca2+ exchange Km for Ca2+, Vmax, and peak uptake and Ca2+ release rate in rat brain PMV. Human frontal cortex was shown to have a greater Na+/Ca2+ exchange activity than that found in the cerebellum. The frontal cortex, temporal cortex and cerebellum had similar Ca2+ permeabilities. Age-related effects on Na+/Ca2+ exchange activity and Ca2+ permeability were determined in 15 tissues from human frontal cortex (age at death 21 to 93 years). No significant age related effects were seen.(ABSTRACT TRUNCATED AT 250 WORDS)

Modified polyvinyl alcohol-benzoporphyrin derivative conjugates as phototoxic agents

Photosensitizing and biodistribution characteristics of a photosensitizer (benzoporphyrin derivative, monoacid ring A; BPD) conjugated to a macromolecule (modified polyvinyl alcohol; M-PVA, molecular weight = 10,000) were tested in vitro and in vivo. Modified PVA was loaded with BPD at molar ratios 1:12, 1:25, 1:50, 1:75 and 1:100. Most of the work was carried out with a conjugate having a 1:25 molar ratio. In vitro photosensitization was tested using A549 (human lung carcinoma), A432 (human epidermoid carcinoma) and P815 (mastocytoma of DBA/2 mice) cell lines. Photosensitization of M1 (rhabdomyosarcoma of DBA/2 mice) tumors was tested in an in vivo/in vitro assay, in which tumor-bearing mice were injected intravenously with free or conjugated 3H-BPD and 3 h later light activation of tumor cells was carried out in vitro. Biodistribution studies were carried out using M1 tumor-bearing DBA/2 mice and 3H-BPD either free or conjugated to M-PVA. The results of these studies showed that the conjugation of BPD to M-PVA resulted in the formation of a macromolecular photosensitizer that retained full photosensitizing activity of the photosensitizer molecules and at the same time gained new characteristics, advantageous for photodynamic treatment, especially in vivo. In vitro M-PVA-BPD conjugates were at least as efficient in photosensitization of tumor cells as an equivalent number of free BPD molecules, both in the presence and in the absence of serum. Although the biodistribution was in general comparable to free BPD, the conjugate (1:25) reached slightly higher levels in the blood, kidney, lung and spleen, and lower levels in the liver, brain, skin and muscle in comparison with free BPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of frozen section and clinical parameters in distinguishing benign from malignant follicular neoplasms of the thyroid

The determination of malignancy preoperatively or intraoperatively is difficult in patients with follicular neoplasms of the thyroid. This study reviews a series of 395 patients treated for follicular neoplasms at the Vancouver General Hospital and the British Columbia Cancer Agency between the years of 1955 and 1988, 198 of whom had frozen section at the time of surgery. Frozen section was 79% accurate in differentiating follicular adenomas from carcinomas, with a sensitivity of 52% and a specificity of 100%. The positive predictive value of a frozen section showing carcinoma was 100%, and the negative predictive value was 73%. An incorrect diagnosis of a benign lesion was made in 21% of patients in whom the final diagnosis by fixed section was carcinoma. These same statistics were calculated for patients aged greater than 50 years, tumor size greater than 3 cm, and patients with a history of previous neck irradiation, three clinical factors shown in a previous study to be strong prognostic indicators of malignancy. The results were compared with those found by frozen section. The implications of these results in terms of patient management are discussed.

Direct association of pp40/I kappa B beta with rel/NF-kappa B transcription factors: role of ankyrin repeats in the inhibition of DNA binding activity

To understand the mechanism by which pp40/I kappa B beta inhibits DNA binding activity of the rel/NF-kappa B family of transcription factors, we have investigated the role of ankyrin repeats on the biological function of pp40 by deleting or mutating conserved residues. We show that (i) ankyrin repeats alone are not sufficient to manifest biological activity but require the C-terminal region of the pp40 protein; (ii) four out of the five ankyrin repeats are essential for inhibiting the DNA binding activity; (iii) pp40 mutants that do not inhibit DNA binding of rel protein also do not associate with rel; (iv) although pp40 can associate with the p65 and p50 subunits of NF-kappa B, pp40 inhibits the DNA binding activity of only the p50-p65 heterodimer and the p65 homodimer; and (v) pp40 inhibits the transcription of genes linked to kappa B site; however, mutants that do not affect DNA binding have no effect. We propose that the ankyrin repeats and the C-terminal region of pp40 form a structure that associates with the rel homology domain to inhibit DNA binding activity.

Rel-associated pp40: an inhibitor of the rel family of transcription factors

The Rel-associated protein pp40 is functionally related to I kappa B, an inhibitor of the transcription factor NF-kappa B. Purified pp40 inhibits the DNA binding activity of the NF-kappa B protein complex (p50:p65 heterodimers), p50:c-Rel heteromers, and c-Rel homodimers. The sequence of the complementary DNA encoding pp40 revealed similarity to the gene encoding MAD-3, a protein with mammalian I kappa B-like activity. Protein sequencing of I kappa B purified from rabbit lung confirmed that MAD-3 encodes a protein similar to I kappa B. The sequence similarity between MAD-3 and pp40 includes a casein kinase II and consensus tyrosine phosphorylation site, as well as five repeats of a sequence found in the human erythrocyte protein ankyrin. These results suggest that rel-related transcription factors, which are capable of cytosolic to nuclear translocation, may be held in the cytosol by interaction with related cytoplasmic anchor molecules.

The rel-associated pp40 protein prevents DNA binding of Rel and NF-kappa B: relationship with I kappa B beta and regulation by phosphorylation

The product of proto-oncogene Rel associates with a number of cellular proteins. We have studied the effect of one of them, a phosphoprotein of 40 kD (pp40), on the DNA-binding activity of the Rel protein. We demonstrate that purified pp40 not only inhibits the binding of Rel, but also NF-kappa B (p50-p65) heterocomplex to DNA. Additionally, I kappa B beta, but not I kappa B alpha, also prevented the binding of Rel to the kappa B site. I kappa B beta and pp40 are related proteins because (1) they share a number of common tryptic peptides, (2) their inhibitory effect on DNA binding can be abolished by preincubation with pp40-specific antiserum, and (3) labeled I kappa B beta can be immunoprecipitated with pp40 antibodies. pp40 is part of the Rel complex present in the cytoplasm and nuclear extracts of WEHI-231 cells. The activity of pp40 to inhibit the DNA binding of Rel and NF-kappa B is modulated by phosphorylation.

Two-year follow-up of bibliotherapy for depression in older adults

The present study examined the long-term benefits of participation in a bibliotherapy program for depressed older adults. Thirty of the original 44 participants (68%) were assessed at approximately 2 years following treatment for clinician-rated and self-rated depression. There were no significant increases in either index suggesting that improvements were maintained. Follow-up questions revealed that most participants (77%) had not received other treatment, most (73%) felt their depression level had decreased, and over half (53%) had read at least parts of their assigned book during the 2-year interval. Results further support the potential for structured bibliotherapy as a treatment adjunct or alternative.

Comparison of three methods for the estimation of total nitrogen losses in hospitalized patients

Since the measurement of total nitrogen output (TNO) is not routinely determined in the clinical setting, its level is frequently estimated using formulas based on the urinary urea nitrogen excretion (UUN). We measured TNO in 124 surgical patients over 990 days (TNO, 19.22 +/- 8.72 g N/day; total urinary nitrogen (TUN) 18.17 +/- 8.70 g N/day; UUN, 15.17 +/- 7.70 g N/day; mean gastrointestinal nitrogen (MGIN) 0.68 +/- 0.49 g N/day; integumental nitrogen (ITGN), 0.34 +/- 0.08 g N/day) and compared the results with the daily estimations using three different formulas: formula A, UUN + 4; formula B, UUN x 1.20 + 1.05, where 1.20 is the reciprocal of the mean ratio UUN/TUN and 1.05 the mean extraurinary nitrogen losses; and formula C, UUN x 1.0986 + 2.55, derived from the regression analysis of UUN vs TNO. TNO estimated by these formulas were 19.17 +/- 7.70, 19.26 +/- 9.24, and 19.22 +/- 8.70 g N/day, respectively. The regression analyses of the estimated TNO from the three formulas versus the measured TNO indicated that formulas A, B and C were equally accurate in estimating TNO over the entire range of UUN. However, when only values of UUN greater than or equal to 30 g N were considered, a modified formula A (UUN + 6) was the best predictor of TNO. Daily audits of the differences between the estimated and measured TNO showed comparable results for the three formulas. In 28.4 to 31.1% of the observed days the differences were higher than +/- 2 g N/day, an error which is not acceptable when estimating the protein requirements in many clinical conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

The v-rel oncogene product is complexed with cellular proteins including its proto-oncogene product and heat shock protein 70

The oncogene product, pp59v-rel, of avian reticuloendotheliosis virus (REV-T) is complexed in the cytosol of REV-T transformed lymphoid cells with cellular proteins. Monoclonal antibodies and antisera directed against different regions of pp59v-rel coimmunoprecipitate five cellular proteins (p124, p115, p75, p70, and p40) in addition to pp59v-rel. Cellular proteins with the same apparent molecular mass also copurify with pp59v-rel during sequential Sephacryl S200 and immunoaffinity chromatography. Antisera directed against the most abundant cellular protein in the complex, pp40, coimmunoprecipitate pp59v-rel and several cellular proteins with the same apparent molecular mass. The 75-kDa protein in the pp59v-rel complex is the product of c-rel proto-oncogene and is weakly phosphorylated. In MSB-1 cells this protein is not detectably phosphorylated or associated with cellular proteins. The 70-kDa protein in the pp59v-rel containing cytosolic complex is the constitutive form of avian heat shock protein 70 (HSC70). The p70 protein coimmunoprecipitates and copurifies with pp59v-rel using antisera directed against pp59v-rel and coimmunoprecipitates with antisera specific for pp40. The p70 isolated from immune complexes containing pp59v-rel shares V8 protease fragments with HSC70.