Is all validation equal? Evaluating sensory- and emotion-focused validation in the context of experimentally induced pain

Validation has been examined in experimental and clinical settings, but examination of whether specific content of validation responses affect pain-related outcomes has not been considered. We examined the impact of sensory- or emotion-focused validation following a pain task. Participants (N = 140) were randomly assigned to one of three validation conditions (i.e. sensory, emotional, or neutral) and completed the cold pressor task (CPT). Participants provided self-report ratings of pain and affective-related variables. Subsequently, a researcher validated emotional, sensory, or no aspects of participants' experience. The CPT was repeated, as were the self-report ratings. No significant differences were observed across conditions in pain or affective outcomes. All conditions reported an increase in pain intensity and pain unpleasantness across CPT trials. These findings suggest validation content may not impact pain outcomes during painful experiences. Future directions to understanding the nuances of validation across interactions and settings are discussed.

Smartphone apps for menstrual pain and symptom management: A scoping review

The past decade marks a surge in the development of mobile apps used to digitally track and monitor aspects of personal health, including menstruation. Despite a plethora of menstruation-related apps, pain and symptom management content available in apps has not been systematically examined. The objective of this study was to evaluate app characteristics, overall quality (i.e., engagement, functionality, design aesthetics, and information), nature and quality of pain and symptom tracking features, and availability and quality of pain-related intervention content. A scoping review of apps targeting facets of the menstrual experience was conducted by searching the Apple App Store. After removal of duplicates and screening, 119 apps targeting menstrual experiences were retained. Pain and menstrual symptoms tracking were available in 64 % of apps. Checkboxes or dichotomous (present/absent) reporting was the most common method of tracking symptoms and was available in 75 % of apps. Only a small subset (n = 13) of apps allowed for charting/graphing of pain symptoms across cycles. Fourteen percent of apps included healthcare professionals or researchers in their development and one app reported use of end-users. Overall app quality measured through the Mobile App Rating Scale (MARS) was found to be acceptable; however, the apps ability to impact pain and symptom management (e.g., impact on knowledge, awareness, behaviour change, etc.) was rated as low. Only 10 % of apps (n = 12) had interventions designed to manage pain. The findings suggest that despite pain and symptom management content being present in apps, this content is largely not evidence-based in nature. More research is needed to understand how pain and symptom management content can be integrated into apps to improve user experiences.

N-aryl piperazine metabotropic glutamate receptor 5 positive allosteric modulators possess efficacy in preclinical models of NMDA hypofunction and cognitive enhancement

Impaired transmission through glutamatergic circuits has been postulated to play a role in the underlying pathophysiology of schizophrenia. Furthermore, inhibition of the N-methyl-d-aspartate (NMDA) subtype of ionotropic glutamate receptors (NMDAR) induces a syndrome that recapitulates many of the symptoms observed in patients with schizophrenia. Selective activation of metabotropic glutamate receptor subtype 5 (mGlu5) may provide a novel therapeutic approach for treatment of symptoms associated with schizophrenia through facilitation of transmission through central glutamatergic circuits. Here, we describe the characterization of two novel N-aryl piperazine mGlu5 positive allosteric modulators (PAMs): 2-(4-(2-(benzyloxy)acetyl)piperazin-1-yl)benzonitrile (VU0364289) and 1-(4-(2,4-difluorophenyl)piperazin-1-yl)-2-((4-fluorobenzyl)oxy)ethanone (DPFE). VU0364289 and DPFE induced robust leftward shifts in the glutamate concentration-response curves for Ca(2+) mobilization and extracellular signal-regulated kinases 1 and 2 phosphorylation. Both PAMs displayed micromolar affinity for the common mGlu5 allosteric binding site and high selectivity for mGlu5. VU0364289 and DPFE possessed suitable pharmacokinetic properties for dosing in vivo and produced robust dose-related effects in reversing amphetamine-induced hyperlocomotion, a preclinical model predictive of antipsychotic-like activity. In addition, DPFE enhanced acquisition of contextual fear conditioning in rats and reversed behavioral deficits in a mouse model of NMDAR hypofunction. In contrast, DPFE had no effect on reversing apomorphine-induced disruptions of prepulse inhibition of the acoustic startle reflex. These mGlu5 PAMs also increased monoamine levels in the prefrontal cortex, enhanced performance in a hippocampal-mediated memory task, and elicited changes in electroencephalogram dynamics commensurate with procognitive effects. Collectively, these data support and extend the role for the development of novel mGlu5 PAMs for the treatment of psychosis and cognitive deficits observed in individuals with schizophrenia.

Subchronic memantine induced concurrent functional disconnectivity and altered ultra-structural tissue integrity in the rodent brain: revealed by multimodal MRI

BACKGROUND

An effective NMDA antagonist imaging model may find key utility in advancing schizophrenia drug discovery research. We investigated effects of subchronic treatment with the NMDA antagonist memantine by using behavioural observation and multimodal MRI.

METHODS

Pharmacological MRI (phMRI) was used to map the neuroanatomical binding sites of memantine after acute and subchronic treatment. Resting state fMRI (rs-fMRI) and diffusion MRI were used to study the changes in functional connectivity (FC) and ultra-structural tissue integrity before and after subchronic memantine treatment. Further corroborating behavioural evidences were documented.

RESULTS

Dose-dependent phMRI activation was observed in the prelimbic cortex following acute doses of memantine. Subchronic treatment revealed significant effects in the hippocampus, cingulate, prelimbic and retrosplenial cortices. Decreases in FC amongst the hippocampal and frontal cortical structures (prelimbic, cingulate) were apparent through rs-fMRI investigation, indicating a loss of connectivity. Diffusion kurtosis MRI showed decreases in fractional anisotropy and mean diffusivity changes, suggesting ultra-structural changes in the hippocampus and cingulate cortex. Limited behavioural assessment suggested that memantine induced behavioural effects comparable to other NMDA antagonists as measured by locomotor hyperactivity and that the effects could be reversed by antipsychotic drugs.

CONCLUSION

Our findings substantiate the hypothesis that repeated NMDA receptor blockade with nonspecific, noncompetitive NMDA antagonists may lead to functional and ultra-structural alterations, particularly in the hippocampus and cingulate cortex. These changes may underlie the behavioural effects. Furthermore, the present findings underscore the utility and the translational potential of multimodal MR imaging and acute/subchronic memantine model in the search for novel disease-modifying treatments for schizophrenia.

Geographic variation in tissue accumulation of endocrine disrupting compounds (EDCs) in grazing sheep

Muscle tissue was collected from ewes and lambs derived from farms throughout Scotland and sample concentrations of five endocrine disrupting compound groups were determined. Farms of origin were categorised according to geographic region. There were few statistically-significant differences with region or distance from cities. However, the magnitude of the difference between the highest and lowest mean values in ewe muscle from different regions exceeded 30% for 13 of the 15 compounds that were consistently detected in muscle, with animals derived from the industrialised region having the highest mean values for 11 of the 13 compounds. A less marked trend was apparent in the lamb muscle (8 of 13 highest were in the industrialised region). The physiological effects of such small differences in exposure to mixtures of pollutants remain to be determined.

Maternal and fetal tissue accumulation of selected endocrine disrupting compounds (EDCs) following exposure to sewage sludge-treated pastures before or after conception

Liver concentrations of selected pollutant classes were determined in groups of sheep fetuses and their dams, at 55 (Experiment 1) and 110 (Experiment 2) days of gestation (term = 145 d) following exposure, throughout their breeding lives and after mating, to pasture treated with either inorganic fertiliser (control, CC) or with sewage sludge (treated, TT). In a unique study designed to separate the respective contributions of environmental sources and mobilised tissue to the available EDC burden, in additional groups of animals, pollutant burdens at 110 days gestation were assessed following exposure to the respective treatments, either throughout their breeding lives until mating, but not thereafter (TC), or only between mating and slaughter (CT) (Experiment 3). With very few exceptions, maternal and fetal liver concentrations of diethylhexyl phthalate (DEHP) and selected polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDE) and polycyclic aromatic hydrocarbons (PAHs) were not significantly affected by sludge exposure in any group. In some cases, maternal and fetal tissue EDC concentrations were different but the differences were not consistent, and maternal and fetal concentrations of none of the classes of chemical were significantly correlated. It was not possible to identify a single chemical, or class of chemical, that may be responsible for previously observed physiological effects of exposure to sludge-treated pastures. It is concluded that exposure of sheep to pastures fertilised with sewage sludge was not associated with increased liver concentrations of EDCs, irrespective of the stage of development at which they were measured and of maternal tissue mobilisation and EDC release during gestation. Thus, retrospective measurements of EDC tissue burdens could not be used to accurately assess earlier fetal EDC insults.

Gene expression profiling of ovine keratinocytes stimulated with Psoroptes ovis mite antigen--a preliminary study

Sheep scab is caused by the noninvasive mite, Psoroptes ovis, which initiates a profound pro-inflammatory skin response leading to lesion development. To investigate these early events between the skin and the parasite, primary ovine epidermal keratinocyte cultures were generated and challenged with mite derived antigens. The kinetics of the mRNA response of these cells were monitored by microarray. The results indicated that the cells responded within 1 h of challenge, with a significant increase in the pro-inflammatory cytokine IL-8. This result was confirmed by real-time RT-PCR, and showed that IL-8 up-regulation was maximal at 1 h but declined to pre-stimulation levels at 24 and 48 h. The IL-8 mRNA response to mite wash antigens containing secretory and/or excretory proteins was also investigated and compared to the response to whole mite antigen. These studies revealed that the mite wash antigen, at a challenge dose of 10 microg/mL, was markedly more potent and induced significantly higher levels of IL-8 mRNA than the same concentration of whole mite antigen. These results are discussed in relation to mite establishment and survival on the ovine host.

Accumulation of endocrine disrupting compounds in sheep fetal and maternal liver tissue following exposure to pastures treated with sewage sludge

Fetal tissue concentrations of endocrine disrupting compounds (EDCs), and their relationship to maternal tissue concentrations, are largely unknown, in any species. In particular, the patterns of accumulation in the respective tissues following increased rates of environmental exposure are little known. This study was designed to determine fetal and maternal tissue concentrations of selected EDCs in sheep exposed to background, environmental concentrations of EDCs (pastures treated with inorganic fertiliser; Control; C) or to elevated, environmental concentrations (sludge-treated pastures; Treated; T). Mean log concentrations of diethylhexyl phthalate (DEHP) were similar in adult and fetal livers but there was a significant interaction between stage of development (maternal or fetal) and treatment reflecting the fact that mean concentrations were lower (P < 0.05) in C than T fetuses but not adults. Relative concentrations of polychlorinated biphenyls (PCB) in maternal and fetal tissue differed with congener; concentrations of congener 101 were higher (P < 0.05) in fetal tissue. Neither maternal nor fetal liver concentrations of any of the PCB congeners differed significantly with treatment. Polybrominated diphenyl ethers (PBDE) in the tissue were represented primarily by congeners 47 and 99. PBDE 99 concentrations were higher in maternal than fetal tissue (P = 0.01). None differed with treatment in either maternal or fetal tissues. Concentrations of many polycyclic aromatic hydrocarbons (PAH) were higher in maternal tissue but none differed with treatment in either adult or fetuses. It is concluded that sheep fetal liver EDC concentrations are variably related to those of their dams and in some cases appear to be selectively accumulated in fetuses. Differential accumulation of individual pollutants may have important implications for the assessment of risk from exposure.

Parallel artificial membrane permeability assay (PAMPA) combined with a 10-day multiscreen Caco-2 cell culture as a tool for assessing new drug candidates

The parallel artificial membrane permeability assay (PAMPA) is extensively used for the evaluation of early drug candidates. It is high throughput, low cost and is amenable to automation. This method has been shown useful in assessing transmembrane, non-energy dependent, diffusion of drugs such that reasonable predictability with in vivo (passive) absorption is possible. Cell cultures mimicking the gastrointestinal tract such as the CACO-2 cultures have the advantage of taking into account other transport mechanism including paracellular and carrier-mediated uptake but are lower throughput and labor-intensive. In this study, the applicability of two high throughput permeability assays namely PAMPA (PSR4p, pION Inc.) and 96-well Caco-2 cell assay (MultiScreen, Millipore) were used to rank drug permeability as well as to predict passive and active drug absorption/secretion for a series of marketed drugs as well as a collection of structurally diverse drug candidates. CACO-2 cells were cultured using MultiScreen hardware over a period of 10 days with the integrity of the cells assessed using transepithelial electrical resistance (TEER) and by the ability of the monolayer to the transport a paracellular marker, sodium fluorescence. Effective permeability (Peff) data were calculated using spectrophotometric data and were binned based on a pre-defined cut-off values as either highly and poorly permeable. A comparison of a well characterized drug training set indicate at least 85% concordance between the data generated from PAMPA and Caco-2 MultiScreen. The values obtained using the MultiScreen approach were also similar to data obtained from the literature using the conventional 21-day Caco-2 cell assay. Differences between PAMPA and CACO-2 ranking were useful indicators of either drug efflux (PAMPA (Peff) > CACO-2 (Peff)) or absorptive transport (CACO-2 (Peff) > PAMPA (Peff)). These results indicate that PAMPA combined with the MultiScreen Caco-2 cell culture may be a useful high throughput screening for predicting passive diffusion and active transport of new drugs.

Preclinical Assessment of the Feasibility of Applying Controlled Release Oral Drug Delivery to a Lead Series of Atypical Antipsychotics

In this paper, we present a preclinical approach for evaluating the feasibility of applying controlled-release (CR) oral drug delivery to increase the duration of exposure and lower the C(max) of compounds in a lead series of short half-life atypical antipsychotics. Three lead compounds in the series had demonstrated potential pharmacological benefits for the treatment of psychosis, in preclinical studies. However, the compounds showed evidence of insufficient half-lives to enable a once-a-day (QD) product using immediate-release (IR) oral delivery. To evaluate and compare the potential for oral CR delivery to extend the duration of action and thereby enable QD administration, the in vitro solubility and permeability, and the duodenal and colonic absorption of three compounds in the series were measured. Based on the results, one candidate was selected for advancement that showed moderate in vitro solubility, but had the highest in vitro permeability and ratio of colonic to duodenal bioavailability (0.9) in the rat. The results from this study provided evidence that a CR drug delivery system could be used to extend the duration of exposure of the compounds in the series and a scientific basis for selecting one of the three compounds as a candidate.

An assessment of the utility of the yeast GreenScreen assay in pharmaceutical screening

In this paper we describe an initial reproducibility study of 12 proprietary compounds followed by the assessment of 51 marketed pharmaceuticals and, lastly, a summary of the data so far from 2698 proprietary compounds from the Johnson & Johnson (J&J) compound library, in the yeast GreenScreen assay (GSA). In this assay, a reporter system in the yeast cells employs the DNA damage inducible promoter of the RAD54 gene, fused to the extremely stable green fluorescent protein (GFP). The assay proved to be very robust, the Excel templates provided by Gentronix with the assay interfaced well with in-house J&J systems with little adaptation, the assay was very rapid to perform and used very little compound. The results confirm previous work which suggests that the yeast GSA detects different classes of genotoxic compounds to the Ames assay and as a result can help screen out important genotoxic compounds at the pre-regulatory test phase that are missed by Ames-test-based screens alone. A combination of SAR evaluation of genotoxicity plus an Ames-test-based screen and the GSA provides a powerful pre-regulatory test battery to aid in the selection of successful drug candidates.

The effects of tracheostomy cuff deflation during continuous positive airway pressure

Continuous flow positive pressure devices bridge the gap between mechanical and unsupported ventilation in patients recovering from critical illness. At this point, patients are often fully awake, yet the inflated tracheostomy cuff prevents them from speaking or swallowing. The aim of this study was to investigate the effects of cuff deflation. After ethics committee approval and informed consent, we recorded airway pressures with catheters placed 3 cm beyond the distal tracheostomy tip, respiratory rate, heart rate and peripheral oxygen saturation with continuous positive airway pressures set at 5, 7.5 and 10 cmH(2)O with the cuff inflated and deflated. Sixteen patients completed the study. There were small falls in end expiratory pressure on cuff deflation. The median (interquartile range) pressure drop with set airway pressure of 5 cmH(2)O was 0.25 (0-1.4) mmHg, which increased to 1 (0-3) mmHg at 7.5 cmH(2)O and 1.5 (0-4) mmHg at 10 cmH(2)O. These changes were not clinically significant and cardiopulmonary parameters remained stable. All patients were able to vocalise following cuff deflation. Twelve patients passed a blue dye swallow screen within a day of tolerating cuff deflation. These results suggest that pressures fall slightly following cuff deflation but this is associated with respiratory stability and may allow patients to talk and swallow.

Suppression of the humoral immune response of Atlantic salmon, Salmo salar L. by the 64 kDa serine protease of Aeromonas salmonicida

Bacteria-free supernatants of broth cultures of Aeromonas salmonicida inhibited the humoral immune response, but not the cell-mediated immune response, of Atlantic salmon to bacteriophage MS2. The immunosuppressive factor was the 64 kDa serine protease secreted by A. salmonicida. The suppressive activity was not due to degradation of epitopes of MS2, and although serine protease degraded the heavy chain of salmon IgM in vitro there was no evidence for significant degradation in vivo. The principal lethal toxin of A. salmonicida, the glycerophospholipid: cholesterol acyltransferase did not inhibit the immune response of salmon.

Generation of novel human MHC class II mutant B-cell lines by integrating YAC DNA into a cell line homozygously deleted for the MHC class II region

The human B lymphoblastoid cell line (LCL) 721.174 sustains a large homozygous deletion in the major histocompatibility complex (MHC) class II region that results in an absence of DQ and DR molecules as well as a deficiency in the assembly and transport of class I molecules to the cell surface. The deleted genes include the transporters associated with antigen processing TAP1 and TAP2, DMA and DMB which are involved in editing class II bound peptides, and four genes whose roles in antigen processing are unclear; the low mass polypeptide genes LMP2 and LMP7, and DNA and DOB. To study this region we have integrated into 721.174 two overlapping yeast artificial chromosome (YAC) clones which cover the interval LMP2-DRA inclusive. Three clones (11.2A1.1, 4D1D10.1 and 4D1D10.2), containing complete copies of the transfected YAC, produced varying levels of mRNA from the LMP, TAP, DQ and DR genes and corresponding levels of LMP and TAP protein. Class I cell surface expression was restored in 11.2A1.1 and 4D1D10.1, as was DR expression in both 4D1D10 transfectants. These studies demonstrate the feasibility of introducing large groups of functional genes back into human lymphoblastoid cells sustaining deletions, with full restoration of biological function. The procedure could be exploited in order to restore all but one gene covered by the deletion, effectively producing a single gene defect. This could be used to introduce copies of genes engineered to contain mutations and to study cis regulatory elements at some distance from the chosen loci.

A primary health care service for Glasgow street sex workers--6 years experience of the "drop-in centre', 1989-1994

In Glasgow, a health and social care centre opened in 1988 principally to facilitate HIV prevention among street prostitutes, most of whom are injecting drug users. During 1992 to 1994, 551 women made 17,554 visits to the medical room which is functional 5 nights per week. The mean age of the sex workers was 26 years (range 15 to 62) and 89% injected drugs. Fifty-five per cent of the attendances were for needle/syringe exchange only whilst the remainder involved other health care provision. Common presenting problems included abscesses, burns and venous thromboses, reflecting the high proportion of sex workers who injected drugs. Most women always used condoms for penetrative commercial sex and symptomatic sexually transmitted disease was seen infrequently. In addition to the provision of injecting equipment and condoms, other key prevention activities included Hepatitis B vaccination and cervical screening. The prevalence of HIV infection amongst the women remains under 5% and most seropositives were known to be infected before the Centre opened. This initiative shows that if multidisciplinary health and social services are provided to street sex workers at a time and place convenient to their work, the benefits are considerable.

Nurse-led clinics. Nurse practitioners managing anticoagulant clinics

A combination of factors resulted in the reconsideration of how the anticoagulant therapy service was offered at Frimley Park Hospital in Camberley. The reduction in available staff led to the introduction of a nurse managed service. This has improved the service by cutting waiting times. Anecdotal evidence suggests that patients value the service. Objective measures of blood results suggest that the nurse-led service manages the patients as well as the previous medically led service.

Behavioral medicine: an emerging field of social work practice

The burgeoning field of behavioral medicine is reviewed in terms of its relevance and implications for social work practice. This article reviews the behavioral medicine paradigm and its applications relevant to social work practice in health care settings. Specific applications of social learning theory to the treatment of cardiac disorders, chronic pain, headaches, obesity, and smoking are reviewed. The manuscript concludes with a review of practice issues.

Enterogastric reflux and gastric clearance of refluxate in normal subjects and in patients with and without bile vomiting following peptic ulcer surgery

A noninvasive scintigraphic technique was used to estimate enterogastric reflux and subsequent gastric evacuation of refluxate in 35 normal, healthy subjects and 55 patients previously treated by vagotomy or partial gastrectomy. Reflux was provoked by a milk drink and quantitated by counting 99Tcm-EHIDA activity within the gastric area during gamma camera imaging. Seven normal subjects (20%) showed reflux of 5-18% of initial activity (mean: 10%), with peak values occurring at 5-30 minutes (mean: 14 minutes) following the milk. Gastric evacuation of activity in these subjects was monoexponential (r = 0.993, T1/2 = 24.1 minutes). Reflux occurred more frequently than normal in patients with truncal vagotomy and drainage (22/28 patients) and partial gastrectomy (20/21 patients). All of 16 patients with Billroth II anastomoses exhibited reflux, which was excessive compared with refluxing normal subjects (mean: 25%; p less than 0.01) and occurred later into the study (mean: 34 minutes; p less than 0.01). Ten of 11 asymptomatic patients showed reflux of similar amounts of activity (mean: 21%) compared with 16 patients who complained of bile vomiting (mean: 22%). However, asymptomatic patients exhibited gastric evacuation of refluxate at a rate similar to that of refluxing normal subjects, while bile vomiters showed significant gastric retention of refluxate at 25-30 minutes following peak gastric activity (p less than 0.05). This result confirms that post-operative bile vomiting is essentially a problem of gastric emptying.

A rapid and sensitive method for measuring ribonucleic acid in ribosomal preparations

By using the fluorescence enhancement of ethidium bromide when it binds to RNA, a very rapid, simple and sensitive assay for the concentration of ribosomal RNA in complex mixtures has been devised.

The effect of problem-oriented medical records on clinical management controlled for patient risks

This study examines the change in clinical management by 28 medical and surgical firms in three London teaching hospitals following the introduction of Problem-Oriented Medical Records (POMR) in one of the hospitals. Comparison is made between firms using and not using POMR. The data are analyzed using a regression model. Analysis is based on the coefficient of change in each firm between the two study years when modified by the physiological and demographic patient variables significantly associated with the management of each disease. Although not conclusive, the results in four of the seven diseases studied encourage the speculation that POMR may have improved the thoroughness of patient management. The significant patient variables in each diagnosis suggest that patient risk on admission can affect management scores. Were this to be found elsewhere, the influences of patient mix might be considered in using explicit criteria to make comparisons between hospitals that serve different kinds of populations.

Investigations into the role of calcium ions in the control of steroid production by isolated adrenal zona glomerulosa cells of the rat

An increase in the concentration of extracellular potassium from 3.6 to 8.4 mmol/1 had only a small delayed effect on the uptake of radioactive calcium by isolated adrenal glomerulosa cells. However, the same stimulus had a rapid and highly significant effect on the efflux of radioactive calcium from glomerulosa cells preloaded with 45Ca2+. Cells incubated in medium containing 8.4 mmol potassium/1 had retained approximately 15% more radioactivity than conrol cells after 2.5 min and this difference was maintained for up to 90 min. There was an increase in the production of steroids by the glomerulosa cells in the presence of 8.4 mM-potassium. No effect on calcium efflux was observed in similar experiments with isolated fasciculata cells; it has been established that this concentration of potassium does not affect steroidogenesis in fasciculata cells, indicating that the effect on glomerulosa cells may be causally linked to steroidogenesis. There was no significant change in the total calcium content of glomerulosa cells in the presence of 8.4 mM-potassium. Exchangeable calcium in these cells was found to be 60% of the total calcium content.

Firm, patient, and process variables associated with length of stay in four diseases

Factors associated with length of stay in three London teaching hospitals during 1972 and 1975 were examined in patients treated for myocardial infarction, cerebrovascular disease, inguinal hernia without obstruction, and gall stones. Statistical analyses were carried out with multiple regressions on log lengths of stay.Increased length of stay was associated with infection in all four groups and with the seriousness of operative procedures in all but patients with cerebrovascular disease. Although age was a significant variable in patients with hernias and gall stones, it had relatively little practical effect on length of stay. Other significant variables in at least one disease were obesity, number of abnormalities in blood chemistry, administration of parenteral fluids or oxygen, or use of monitoring devices, and whether chest radiography was carried out, blood electrolytes and urea were measured, or anticoagulants were used. Patients with cerebrovascular disease who were not discharged to their own homes stayed on average more than two and a half times longer than other patients.Between a third and a half of the variance was explained by these variables and the variation among firms. The method described is reproducible in other hospital settings, and the study shows that much new information could be available routinely without mounting expensive field trials.

Communication as a method of medical audit

Advances in the practice of medicine over the past forty years have rendered informal communication ineffective in setting and maintaining standards of clinical care. In the past five years, four methods in communication have been introduced in the department of surgery at Guy's Hospital: problem-oriented medical records, death-and-complications meetings, unit review meetings, and a clinical information service. It is suggested that these can achieve quality control.

Relation of intracellular K+ and steroidogenesis in isolated adrenal zona glomerulosa and fasciculata cells

1. Intracellular K+ content, water spaces and corticosterone output were measured in isolated zona glomerulosa and zona fasciculata-reticularis cell suspensions of rat adrenal cortex, after incubation in vitro under conditions designed to alter steroidogenesis. 2. Intracellular K+ of unpurified zona glomerulosa cells was not altered after stimulation of corticosterone output with serotonin. Similarly, with zona glomerulosa cells purified by unit gravity sedimentation, no change in intracellular K+ was detected after stimulation of steroidogenesis with serotonin or angiotensin II. 3. In high-potassium medium (final concentration 8.4 mmol/1), parallel increases in intracellular K+ and corticosterone output were observed with both purified zona glomerulosa cells. However, a similar increase in intracellular K+ also occurred in high-potassium medium with zona fasciculata cells, whose steroid output is unresponsive to external potassium concentration ([K+]). 4. Ouabain at 10(-5) mol/1 depressed the intracellular [K+] of glomerulosa cells but did not alter basal or stimulated corticosterone output. Similar results were obtained with fasciculata cells. 5. Ouabain at 5 times 10(-4) mol/1 further depressed intracellular [K-+] of glomerulosa cells and inhibited basal and stimulated corticosterone output. However, this concentration of ouabain also inhibited steroidogenesis in fasciculata cells. 6. These results demonstrate a variety of situations where changes in intracellular [K+] are dissociated from those in corticosterone output and indicate that intracellular [K+] cannot be the sole mechanism regulating steroidogenesis under these conditions.