Participant observation as a research tool in a practice based profession

This paper by Catriona Kennedy offers a personal account of the use of participant observation as a tool for exploring and uncovering the knowledge base of experienced district nurses in relation to first assessment visits. Currently, many district nurses (DNs) are educated to degree level. However, despite a long history of educational provision for DNs, the research base available to support their practice is limited.

The gene for hypotrichosis of Marie Unna maps between D8S258 and D8S298: exclusion of the hr gene by cDNA and genomic sequencing

Hypotrichosis of Marie Unna (MU) is an autosomal dominant hair-loss disorder with onset in childhood. A genomewide search for the gene was performed in a large Dutch family using 400 fluorescent microsatellite markers. Linkage was detected with marker D8S258, and analysis of this family and a further British kindred with additional markers in the region gave a combined maximum two-point LOD score of 13.42, with D8S560. Informative recombinants placed the MU gene in a 2.4-cM interval between markers D8S258 and D8S298. Recently, recessive mutations in the hr gene were reported in families with congenital atrichia, and this gene was previously mapped close to the MU interval. By radiation-hybrid mapping, we placed the hr gene close to D8S298 but were unable to exclude it from the MU interval. This, with the existence of the semidominant murine hr allele, prompted us to perform mutation analysis for this gene. Full-length sequencing of hr cDNA obtained from an affected individual showed no mutations. Similarly, screening of all exons of the hr gene amplified from the genomic DNA of an affected individual revealed no mutations. Analysis of expressed sequences and positional cloning of the MU locus is underway.

The Internet in managed health care

Blue Shield of California recognized it could realize business gains by implementing solutions that would streamline health care administration. It began looking for opportunities to apply the Internet to the core business and defining which of those services would benefit quickly from implementation. It selected Internet technology from Healtheon Corp., a Silicon Valley startup in Palo Alto, California.

Vitamin E up-regulates arachidonic acid release and phospholipase A2 in megakaryocytes

The release of arachidonic acid is the rate limiting step in eicosanoid synthesis. In mammalian cells, the release of arachidonic acid is catalyzed by several enzymes. The 85 kDa cytosolic phospholipase A2 (cPLA2) is the key enzyme for the release reaction because of its specific acyl selectivity in phospholipid substrates. We have previously reported that vitamin E enrichment potentiates the arachidonic acid release as well as the spontaneous prostacyclin release in human endothelial cells. In contrast, similar enrichment of diets caused a dose-dependent suppression of platelet thromboxane synthesis. Therefore, the present study was undertaken to determine the effect of vitamin E on arachidonate release and phospholipaseA2 activity in a platelet precursor cell, the MEG-01 megakaryocyte cell line. When these cells were incubated with different concentrations of vitamin E, cellular incorporation was linear with the dosages of this vitamin. Determination of arachidonate release after labeling cells with [3H]-arachidonate showed that vitamin E enrichment caused a dose-dependent increase in ionophore A23187-induced [3H]-arachidonic acid release. Analysis of PLA2 activity showed that activity was detected in the cytosol and this activity was completely abolished by the addition of anti-cPLA2, antibody. Determination of cPLA2 activity demonstrated that vitamin E enrichment caused an increase in enzyme activity. Analysis of cPLA2 protein by Western blot revealed that vitamin E caused an increase in enzyme protein. These data showed that the potentiation of arachidonic acid release and cPLA2, activity by vitamin E was mediated by the enhanced expression of cPLA2 protein.

An audit of children referred with suspected epilepsy

Members of the British Paediatric Neurology Association were invited to participate in a national audit of children presenting with a possible diagnosis of epilepsy. The audit was based on a 'standard' or set of pre-determined questions drawn up by an advisory audit group. The audit form comprised a total of 30 questions divided into four sections addressing history, examination, investigation, treatment and communication. Information for the audit was obtained retrospectively from the child's case notes. Each participating centre or consultant was asked to audit the case notes of 20 children. At the end of the 12-month recruitment period three centres responded, contributing audit forms on 50 children. The required information was provided for the majority of the questions in each of the four sections, thereby meeting the audit 'standard'. Within the history section, only 32 of the 50 (64%) case notes had recorded whether or not there was 'any obvious provoking factor or circumstance to the episodes'. Communication was the least satisfactorily completed section with between none and 48% of the case notes documenting that the child's family had been informed of the existence of a voluntary epilepsy organization. Despite the simplicity of the audit form, the response for this national audit was considerably lower than anticipated.

Tumour necrosis factor stimulates stress-activated protein kinases and the inhibition of DNA synthesis in cultures of bovine aortic endothelial cells

In this study, we examined the ability of tumour necrosis factor-alpha (TNF) to stimulate the mitogen-activated protein (MAP) kinase homologues p42/44 MAP kinase, c-Jun NH2-terminal kinase (JNK) and p38 MAP kinase and its effect upon DNA synthesis in primary cultures of bovine aortic endothelial cells (BAECs). TNF strongly stimulated p38 MAP kinase and JNK activity in both a time- and concentration-dependent manner. By contrast, TNF was a very poor activator of p42/44 MAP kinase relative to the known activator of p42/44 MAP kinase in endothelial cells, adenosine triphosphate (ATP). TNF-stimulated activation of p38 MAP kinase, and MAPKAP kinase-2, a known downstream target of p38 MAP kinase, was strongly inhibited by pre-incubation with the p38 MAP kinase inhibitor SB203580, whereas the minor activation of p42/44 MAP kinase was abolished by pre-incubation of the cell with the novel MAP kinase kinase 1 inhibitor PD098059. Addition of TNF resulted in a 50-60% decrease in DNA synthesis in BAECs. Pre-incubation with PD098059 or co-incubation with ATP failed to modify the inhibitory effect of TNF upon DNA synthesis. SB203580 reduced basal DNA synthesis by approximately 50%; however, if failed to modify the inhibition mediated by TNF. These results indicate that TNF strongly activates both p38 MAP kinase, JNK and, to a minor extent, p42/p44 MAP kinase. It is likely that only one of these kinases, JNK, plays a role in the regulation of DNA synthesis in these cells.

The generation of human gammadelta T cell repertoires during fetal development

The nature of how human gammadelta T cells are normally generated is not clear. We have used an RT-PCR assay and DNA sequencing to identify and compare delta-encoded TCRs (TCRDs) that are generated de novo in the fetal gut, liver, and thymus and to determine when, where, and how the TCRD repertoire is established during normal embryonic development. Rearranged TCRDV genes are first expressed outside of the thymus in the liver and primitive gut between 6 and 9 wk gestation. Although DV1Rs and/or DV2Rs predominated, differences in the pattern of TCRDV gene rearrangement and transcription in each tissue during ontogeny were identified. Specific, DV2-encoded TCRs are highly conserved throughout ontogeny in the tissues from the same and between genetically distinct donors. Although the thymic and intestinal gammadelta T cell repertoires partially overlap early in development, they diverge and become nonoverlapping during the second trimester, and the generation of the intestinal gammadelta T cell repertoire is characterized by differences in the processing of DV1Rs and DV2Rs. Whereas the structural diversity of DV1Rs progressively increases during gut development up to birth, DV2Rs have limited structural diversity throughout ontogeny. Together, our findings provide evidence for the ability of different fetal tissues to support the development of gammadelta T cells.

Comparison of the actions of ATP and UTP and P(2X1) receptors in smooth muscle of the rat tail artery

The actions of ATP and uridine 5'-triphosphate (UTP) were compared at P2X1 receptors in acutely dissociated smooth muscles cells of the rat tail artery. ATP (30 nM-100 microM) and UTP (1 microM-1 mM) elicited concentration-dependent inward currents. ATP was approximately 100-fold more potent than UTP. In both cases, currents were activated within 3 ms of agonist application and had similar time-courses of activation and inactivation. The decay of responses for both agonists was concentration-dependent and in most cells could be fitted by two exponentials. The P2X receptor antagonists suramin (100 microM) and pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS, 5 microM) inhibited responses to both ATP and UTP. An action of UTP at P2X1 receptors has not previously been reported. However, since the responses to ATP and UTP had similar time-courses and as PPADS and suramin inhibited both agonists, it is concluded that ATP and UTP are acting at the same site in these cells, the P2X1 receptor.

Characterization of the glnK-amtB operon of Azotobacter vinelandii

To determine whether in Azotobacter vinelandii the PII protein influences the regulation of nif gene expression in response to fluxes in the ammonium supply, the gene encoding PII was isolated and characterized. Its deduced translation product was highly similar to PII proteins from other organisms, with the greatest degree of relatedness being exhibited to the Escherichia coli glnK gene product. A gene designated amtB was found downstream of and was contranscribed with glnK as in E. coli. The AmtB protein is similar to functionally characterized ammonium transport proteins from a few other eukaryotes and one other prokaryote. glnK and amtB comprise an operon. Attempts to isolate a stable glnK mutant strain were unsuccessful, suggesting that glnK, like glnA, is an essential gene in A. vinelandii. amtB mutants were isolated, and although growth on limiting amounts of ammonium was similar in the mutant and wild-type strains, the mutants were unable to transport [14C]methylammonium.

Pharmacological properties of P2X3-receptors present in neurones of the rat dorsal root ganglia

1. The electrophysiological actions of several agonists which may differentiate between P2X1- and P2X3-receptors were studied under concentration and voltage-clamp conditions in dissociated neurones of 1-4 day old rat dorsal root ganglia. 2. Beta,gamma-Methylene-D-ATP (beta,gamma-me-D-ATP) (1-300 microM), diadenosine 5',5'''-P1,P5-pentaphosphate (AP5A) (100 nM - 300 microM), diadenosine 5',5'''-P1,P4-tetraphosphate (AP4A) (300 nM - 300 microM) and uridine 5'-triphosphate (UTP) (1 microM - 1 mM) all activated concentration-dependent inward currents with a latency to onset of a few ms. 3. The concentration-response curves for beta,gamma-me-D-ATP and AP5A and ATP had similar maximum values, while that for AP4A had a lower maximum. The concentration-response curve to UTP was shallow and did not reach a maximum. Beta,gamma-Methylene-L-ATP was virtually inactive. The rank order of agonist potency was ATP > AP5A approximately AP4A > beta,gamma-me-D-ATP > UTP > > beta,gamma-methylene-L-ATP. 4. The inward currents were inhibited by the P2-receptor antagonists suramin (100 microM) and pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS) (10 microM). PPADS also inhibited responses to ATP (800 nM) and alpha,beta-methylene ATP (2 microM) in a concentration-dependent manner. 5. This study shows that beta,gamma-me-D-ATP, AP5A, AP4A and UTP all act via a suramin- and PPADS-sensitive P2X-receptor to evoke rapid, transient inward currents in dissociated neurones of rat dorsal root ganglia. The very low activity of beta,gamma-methylene-L-ATP suggests that the agonists were acting at the P2X3-subtype to produce these effects.

Evidence that ATP acts at two sites to evoke contraction in the rat isolated tail artery

1. The site(s) at which P2-receptor agonists act to evoke contractions of the rat isolated tail artery was studied by use of P2-receptor antagonists and the extracellular ATPase inhibitor 6-N,N-diethyl-D-beta,gamma-dibromomethyleneATP (ARL 67156). 2. Suramin (1 microM(-1) mM) and pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS) (0.3-300 microM) inhibited contractions evoked by equi-effective concentrations of alpha,beta-methyleneATP (alpha,beta-meATP) (5 microM), 2-methylthioATP (2-meSATP) (100 microM) and adenosine 5'-triphosphate (ATP) (1 mM) in a concentration-dependent manner. Responses to alpha,beta-meATP and 2-meSATP were abolished, but approximately one third of the peak response to ATP was resistant to suramin and PPADS. 3. Contractions evoked by uridine 5'-triphosphate (UTP) (1 mM) were slightly inhibited by suramin (100 and 300 microM) and potentiated by PPADS (300 microM). 4. Desensitization of the P2X1-receptor by alpha,beta-meATP abolished contractions evoked by 2-meSATP (100 microM) and reduced those to ATP (1 mM) and UTP (1 mM) to 15+/-3% and 68+/-4% of control. 5. Responses to alpha,beta-meATP (5 microM) and 2-meSATP (100 microM) were abolished when tissues were bathed in nominally calcium-free solution, while the peak contractions to ATP (1 mM) and UTP (1 mM) were reduced to 24+/-6% and 61+/-13%, respectively, of their control response. 6. ARL 67156 (3-100 microM) potentiated contractions elicited by UTP (1 mM), but inhibited responses to alpha,beta-meATP (5 microM), 2-meSATP (100 microM) and ATP (1 mM) in a concentration-dependent manner. 7. These results suggest that two populations of P2-receptors are present in the rat tail artery; ligand-gated P2X1-receptors and G-protein-coupled P2Y-receptors.

District nurses' knowledge and practice of wound assessment: 2

The first article in this series reported a study that examined the wound assessment practices of 20 district nurses in one healthcare trust. The most common method of assessing wounds was found to be a combination of observation and experience (Vol 7(7): 380-6). This article, the second part, describes the subsequent establishment of a forum to develop a research-based wound assessment tool. The issues surrounding changing practice are complex. It is clear that the process of basing practice on evidence is the responsibility of all those who are involved in healthcare. However, there is an urgent need to bring the practice, research and education agenda closer with organizational and managerial commitment to change. This work suggests that a short-term increase in resources will result in possible long-term benefits for patient care.

District nurses' knowledge and practice of wound assessment: 1

Nurses are expected to implement knowledge gained through research into their practice to ensure the delivery of high quality and effective care. As district nurses spend a significant proportion of their time on wound care, a sound knowledge base is essential. The first part of this two-part article reports a study that examined the wound assessment practices of 20 district nurses in one healthcare trust. The most common method of assessing wounds was found to be a combination of observation and experience. Assessment using observation or experience without documentation may be subjective, variable between practitioners and unreliable or inaccurate. The second part of this article, to be published in the next issue, will describe the subsequent establishment of a forum to develop a research-based wound assessment tool.

Telemedicine applications in an integrated mental health service based at a teaching hospital

Psychiatric applications have predominated in Australian telemedicine in recent years. This paper describes the development of the first telemedicine system for an integrated mental health service based at a teaching hospital. Much effort was devoted to training and education for staff. Within about six weeks of the system being installed, over 80% of all clinical administrative staff, from all the mental health disciplines of the integrated service, had completed a formal training programme. Applications within the service included direct clinical work and the use of videoconferencing in preference to standard telephony over short distances. Applications external to the service, over distances of thousands of kilometres, included clinical supervision and teaching. Evaluation is continuing.

Attitudinal changes toward exercise in mexican american women

BACKGROUND

This experimental study was designed to examine the attitude changes and exercise adherence of a group of sedentary minority women.

METHOD

Fifty sedentary Mexican American women participated in a 9-month, biweekly education and exercise program that was preceded by a 6-month program initiation composed of weekly interactions to facilitate trust between participants and researchers.

RESULTS

Compared to Mexican American and Caucasian control groups, the experimental participants displayed significant changes in scores on the Exercise Benefits and Barriers Scales (EBBS) at three, six, and nine months. Adherence to the physical activity program was 84%. At pre-test, the Mexican American participants and controls displayed significantly lower EBBS scores than the Caucasian controls.

CONCLUSIONS

The results of this study are examined in light of existing reports on the facilitation of attitudes toward exercise, exercise adherence and health promotion particularly in regard to understanding the barriers to physical activity for minorities. The findings of this study are particularly important given the paucity of research about health promotion for individuals who belong to minority groups.

Blockade of cerebral blood flow response to insulin-induced hypoglycemia by caffeine and glibenclamide in conscious rats

The possibility that adenosine and ATP-sensitive potassium channels (KATP) might be involved in the mechanisms of the increases in cerebral blood flow (CBF) that occur in insulin-induced hypoglycemia was examined. Cerebral blood flow was measured by the [14C]iodoantipyrine method in conscious rats during insulin-induced, moderate hypoglycemia (2 to 3 mmol/L glucose in arterial plasma) after intravenous injections of 10 to 20 mg/kg of caffeine, an adenosine receptor antagonist, or intracisternal infusion of 1 to 2 mumol/L glibenclamide, a KATP channel inhibitor. Cerebral blood flow was also measured in corresponding normoglycemic and drug-free control groups. Cerebral blood flow was 51% higher in untreated hypoglycemic than in untreated normoglycemic rats (P < 0.01). Caffeine had a small, statistically insignificant effect on CBF in normoglycemic rats, but reduced the CBF response to hypoglycemia in a dose-dependent manner, i.e., 27% increase with 10 mg/kg and complete elimination with 20 mg/kg. Chemical determinations by HPLC in extracts of freeze-blown brains showed significant increases in the levels of adenosine and its degradation products, inosine and hypoxanthine, during hypoglycemia (P < 0.05). Intracisternal glibenclamide had little effect on CBF in normoglycemia, but, like caffeine, produced dose-dependent reductions in the magnitude of the increases in CBF during hypoglycemia, i.e., +66% with glibenclamide-free artificial CSF administration, +25% with 1 mumol/L glibenclamide, and almost complete blockade (+5%) with 2 mumol/L glibenclamide. These results suggest that adenosine and KATP channels may play a role in the increases in CBF during hypoglycemia.

Perseverative behavior in Alzheimer's disease and subcortical ischemic vascular dementia

Perseverative behavior has not been extensively studied in patients with dementia. In this study, perseverative behavior was elicited with the dementia version of the Graphical Sequence Test. A control group and participants with Alzheimer's disease (AD) and subcortical ischemic vascular dementia (IVD) were studied. A factor analysis revealed a 3-factor model consisting of perseverations related to semantic knowledge, motor functioning, and a third, intermediary factor. IVD participants made more total perseverations than did AD participants. Perseverations made by AD participants were correlated with deficits on tests of semantic knowledge, whereas the perseverations made by IVD participants were correlated with motor and frontal systems tests. Results are consistent with the view that perseverative behavior is hierarchically arranged in terms of specific levels of cognitive complexity and the overall pattern of cognitive deficits associated with each type of dementia.

Using uncovered metallic endoprostheses to treat recurrent benign esophageal strictures

OBJECTIVE

The management of recurrent benign esophageal strictures is a difficult clinical problem, especially in patients who are not surgical candidates. We evaluated the role of uncovered metallic endoprostheses in four patients who had strictures that were resistant to repeated balloon dilatation.

CONCLUSION

Our preliminary experience indicates that uncovered metallic endoprostheses can be effective in treating a select group of patients who have benign esophageal strictures and for whom multiple dilatations have failed. It is also important to note that epithelial hyperplasia can result in stenoses and recurrent dysphagia.

Breast cancer in young women

BACKGROUND

It is believed that cancer of the breast is more difficult to diagnose in young women and it has long been disputed whether breast cancer occurring in women aged < or = 40 years is more aggressive than that occurring later in life. A number of reports in the literature suggest that the disease is of similar aggressiveness in the young patients and older age groups, while other reports suggest that it is more aggressive and carries a higher mortality in young women.

METHODS

To address these aspects of breast cancer we have undertaken a review of the cases treated at The Strathfield Breast Centre between 1989 and 1996 and compared the disease in the young and old groups with particular reference to the modes of diagnosis, the pathological staging and types of tumour and the outcomes of treatment.

RESULTS

The accuracy of ultrasound and fine needle aspiration biopsy were similar in both groups, but the false negative rate of mammography in the young patients was 15% or 50% greater than that which was observed in the older patients. The incidence of histopathological type, bilaterality, size of lesion and receptor positivity were the same in both groups. In the young group, 40% had Grade 3 tumours compared with 27% in the older group. Nineteen per cent of young patients had 4 or more lymph nodes involved while only 10% of the older patients had similar lymph node involvement. Overall 5-year survival was 79% in the older patients compared with 90% in the young patients.

CONCLUSIONS

The spectrum of disease is similar in both the young and older patient and the prognosis is no worse for the young group but mammography is less effective in the diagnosis of the young patient.

Perseverative behavior in Alzheimer's disease and subcortical ischemic vascular dementia

Perseverative behavior has not been extensively studied in patients with dementia. In this study, perseverative behavior was elicited with the dementia version of the Graphical Sequence Test. A control group and participants with Alzheimer's disease (AD) and subcortical ischemic vascular dementia (IVD) were studied. A factor analysis revealed a 3-factor model consisting of perseverations related to semantic knowledge, motor functioning, and a third, intermediary factor. IVD participants made more total perseverations than did AD participants. Perseverations made by AD participants were correlated with deficits on tests of semantic knowledge, whereas the perseverations made by IVD participants were correlated with motor and frontal systems tests. Results are consistent with the view that perseverative behavior is hierarchically arranged in terms of specific levels of cognitive complexity and the overall pattern of cognitive deficits associated with each type of dementia.

Pulmonary resection for metastatic breast cancer

BACKGROUND

A patient with a solitary pulmonary metastasis who had breast cancer in the past may benefit from pulmonary resection.

METHODS

Between 1984 and 1996, 17 patients underwent metastatectomy for metastatic breast cancer. There were 15 females and two males whose average age was 59 (range: 40-74 years). The median tumour-free interval after the primary breast-cancer operation was 5.1 years (range: 8 months-18.2 years). Sixteen patients had complete resections, which included six lobectomies and 10 lesser resections.

RESULTS

The postoperative mortality was nil and the morbidity rate was 6%. Follow-up was complete in all patients. Recurrent disease developed in four patients and two patients died of their disease. The 5-year survival was 62%.

CONCLUSION

An aggressive surgical approach is warranted in patients with isolated resectable pulmonary metastases from breast cancer.

Gallstone dissolution with oral bile acid therapy. Importance of pretreatment CT scanning and reasons for nonresponse

In patients with cholesterol-rich gallbladder stones and a patent cystic duct, complete stone clearance rates of 65-90% have been reported with oral bile acids (OBAs) alone or with adjuvant lithotripsy (extracorporeal shock-wave lithotripsy; ESWL). The aims of the present study were to analyze pretreatment gallstone characteristics that predict the speed and completeness of dissolution with OBAs +/- ESWL, and to assess, in patients with incomplete dissolution, the reasons for the poor response. We compared pretreatment gallstone characteristics in 43 patients who became stone-free after a median of 9 months OBAs +/- ESWL with those in 43 age- and sex-matched patients whose stones failed to dissolve after two years of treatment. In those with incomplete gallstone dissolution, we repeated the oral cholecystogram and computed tomogram (CT) and, in selected patients, obtained gallbladder bile by percutaneous fine-needle puncture. In patients who became stone-free, those with stones that were isodense with bile and/or had CT scores of < 75 Hounsfield units had the fastest dissolution rates. In the 43 nonresponders, the main causes for treatment failure were impaired gallbladder contractility and acquired stone calcification. CT-lucent, noncholesterol stones, or failure of desaturation of bile with the prescribed bile acids, occurred in a minority. We conclude that the pretreatment CT attenuation score predicts both the speed and completeness of gallstone dissolution. In patients with incomplete stone dissolution, the combination of oral cholecystography, CT, and analysis of gallbladder bile will determine the underlying reasons for treatment failure in most, but not all, cases.