VACUTEX capillary action dressing: a multicentre, randomized trial

This article describes a preliminary study comparing the effect of VACUTEX capillary action wound dressing vs standard protocol for the treatment of sloughy and necrotic wounds. The study was carried out over a period of 5 months. Randomization was computer generated and batches of trial numbers and dressing allocation were delivered to each of the three study sites, sealed in opaque envelopes to ensure blinding of allocation. A total of 35 patient participants were recruited (17 VACUTEX 14, standard protocol, three withdrew, one died). All participants gave their consent to enter the study. All participants were assessed and photographs were taken on days 1, 8, 15, 22 and 29. Nursing assessments of size, site, depth, severity, tissue type of wound and causation were collected, as were demographic factors including mental status, primary/associated medical history, weight, height, and ethnic origin.

Design, expression and functional characterization of a synthetic gene encoding the Chlamydia trachomatis major outer membrane protein

A synthetic gene coding for the Chlamydia trachomatis serovar L2 major outer membrane protein (MOMP) was designed, constructed and expressed in Escherichia coli. The native amino acid sequence was reverse translated and the resulting nucleotide combinations manipulated in order to evenly distribute 25 unique restriction sites along the length of the gene while retaining the native amino acid sequence. The synthetic gene was cloned into a T7 promoter-controlled plasmid (pET-3a) and the expressed product was analyzed to assess antigenicity, cellular localization and function. Monoclonal antibodies specific for native MOMP reacted to the expressed product by immunoblot. Outer membrane fractionation confirmed that the processed protein was located in the outer membrane. MOMP expressed in E. coli and present in the outer membrane was shown to function as a general diffusion porin. This system provides the means to produce readily modifiable MOMP either in purified form or as a membrane-associated protein, and so facilitate the investigation of its functional, structural and antigenic properties.

Striatal and extra-striatal D(2)/D(3) dopamine receptor occupancy by quetiapine in vivo. [(123)I]-epidepride single photon emission tomography(SPET) study

BACKGROUND

Selective action at limbic cortical dopamine D(2)-like receptors could mediate atypical antipsychotic efficacy with few extrapyramidal side-effects.

AIMS

To test the hypothesis that quetiapine has 'limbic selective' D(2)/D(3) receptor occupancy in vivo.

METHOD

The high-affinity D(2)/D(3) ligand [(123)I]-epidepride and single photon emission tomography were used to estimate D(2)/D(3) specific binding and an index of relative percentage D(2)/D(3) occupancy in striatal and temporal cortical regions for quetiapine-treated patients (n=6). Quetiapine-, and previously studied typical-antipsychotic- and clozapine-treated patients were compared.

RESULTS

Mean (s.d.) relative percentage D(2)/D(3) receptor occupancy by quetiapine was 32.0% (14.6) in striatum and 60.1% (17.2) in temporal cortex (mean daily dose 450 mg: range 300-700 mg/day). Quetiapine treatment resulted in limbic selective D(2)/D(3) blockade similar to clozapine and significantly higher than typical antipsychotics.

CONCLUSIONS

Preliminary data suggest that limbic selective D(2)/D(3) receptor blockade is important for atypical drug action.

Experienced nurses learning with medical students: a case study

Although there are successful examples of interdisciplinary education this generally relates to pre-registration health-care professionals. Post-registration projects are usually confined to skills workshops or social science subjects, which rarely include medical staff. This project was unusual in its attempt to combine the needs of experienced practitioners with those of medical students. There are practical issues for this form of learning such as, the organization of modules into 'systems' when health-care professionals (as part of a parallel project) indicated their interests lay in courses that related to clinical practice organized around disease processes/conditions. This case study demonstrates that concerns related to the potential mismatch of clinical expertise, maturity and scientific background are not insurmountable problems, and that clear benefits can be gained. It could be argued that until pre- and post-graduate medical staff are integrated with other disciplines, the real benefits of shared understanding, enhanced team work and mutual respect will remain illusive. It is not anticipated that this form of learning would be suitable for the majority of practitioners, whose core needs are generally met by existing opportunities. However, there is a need for a greater depth of academic understanding particularly for those in senior positions or in specific specialized areas (also identified in the parallel study) and for those whose roles are expanding. These practitioners are more likely to have the ability to apply their new knowledge to clinical practice, using reflective techniques with minimal facilitation to enhance their established clinical expertise. For them this model of learning offers the opportunity to tailor education to the individual needs of the practitioner without the costly establishment of complete new programmes of learning. This case study proved particularly successful for the participants as they enhanced understanding and confidence in the knowledge underpinning their practice. This enabled them to better anticipate patients needs, to identify complications and initiate action at an earlier stage. Their appreciation of rationale underpinning medical treatment has enabled them to support junior medical staff, and to promote the continuity of appropriate care. They are more active in the education of patients, relatives and staff, and have identified specific developments which will be informed by the knowledge they have gained. It also proved beneficial to junior medical staff with whom interdisciplinary working has improved. Each organization involved in facilitating the initiative also benefited by gaining mutual understanding and appreciation of systems, constraints and opportunities. Equally, relationships among them have been strengthened and key issues with practical solutions have been identified to inform future joint ventures. Indications suggest that there would be value in using this case study to inform a structured pilot project involving other modules of learning and potentially other disciplines. If successful it could benefit all health-care professionals, particularly those senior staff who are expanding their roles and have educational needs unmet by existing provision. In addition to providing complementary opportunities this format provides a mechanism to enhance the mutual understanding essential to effective teamwork.

Introducing a lecturer-practitioner: the management perspective

The West Midlands Regional Health Authority Department of Nursing funded a 1-year study to look at 'Implementation aspects of the lecturer-practitioner role (in nursing)'. A feasibility study was carried out from November 1992 to October 1993 to address the issue and highlight areas requiring more in-depth study. Twenty-nine subjects working as or with lecturer-practitioners were interviewed using a semi-structured questionnaire. The interview was divided into two discrete parts. The first section contained a mixture of open and closed questions and the second section adopted a modified repertory grid technique. This paper provides the main results from the first half of the interview. The study describes in practical terms how managers need to plan for the introduction of a lecturer-practitioner post; the key responsibilities of the role; and a person specification. The work identifies clear prerequisite criteria for job role and gives guidance on lecturer-practitioner management and function.

Re-evaluation of hyaluronidase in peribulbar anaesthesia

AIMS/BACKGROUND

Hyaluronidase can augment the actions of local anaesthetics in peribulbar anaesthesia. However, evidence suggests satisfactory anaesthesia can be achieved using mixtures without hyaluronidase. A randomised double blind study was conducted on 50 patients, undergoing peribulbar anaesthesia, to validate this observation.

METHODS

Patients received a standard mixture of local anaesthetic (0.5% bupivacaine and 2% lignocaine in a 1:1 ratio) with or without hyaluronidase (25 IU/ml of mixture), pH values 5.16 and 5.24 respectively. Time taken to establish satisfactory anaesthesia to allow surgery was noted.

RESULTS

The onset time to globe akinesia in the control group ranged from 2 to 15 minutes (mean 5.64 and median 4 minutes) and in the hyaluronidase group from 2 to 12 minutes (mean 4.64 and median 4 minutes). The volume of local anaesthetic injected to achieve satisfactory anaesthesia ranged from 8 to 16 ml (mean 10.96, SD 1.95) in the control group and 10 to 18 ml (mean 11.64, SD 2.8) in the hyaluronidase group. A Mann-Whitney test to compare onset times to globe akinesia between groups gave a p value = 0.6 and 95% confidence interval (-1 to 2 minutes).

CONCLUSION

Addition of 25 IU/ml of hyaluronidase to a standard pH unadjusted local anaesthetic mixture does not significantly reduce the time to the onset of satisfactory globe akinesia.

Family reactions to restraints in an acute care setting

1. Families do not realize that a patient has a right to refuse restraints and that the family members have a voice in the decision-making process. 2. Families in general are interested in restraint issues but do not have information at their disposal. 3. Nursing staff should be encouraged to educate family members regarding restraints through open communication and printed material.

Accessory cells do not contribute to G-CSF or IL-6 production nor to rapid haematological recovery following peripheral blood stem cell transplantation

Haemopoietic recovery is more rapid after peripheral blood stem cell (PBSC) transplantation than after autologous bone marrow transplantation, and the aim of this study was to assess the role of the large number of lymphocytes and monocytes (accessory cells) in a PBSC leukapheresis product in this rapid regeneration. Haematological recovery was therefore assessed in 10 PBSC recipients with lymphoma or myeloma in whom monocytes and T cells were depleted by a median of 2.3 and 3.3 logs by CD34+ cell selection using the CEPRATE SC stem cell concentration system and compared with recovery in 59 recipients who received whole PBSC. After allowing for the number of progenitor cells reinfused, there was no significant delay in engraftment induced by accessory cell depletion. Plasma levels of granulocyte-colony stimulating factor (G-CSF), granulocyte/monocyte-colony stimulating factor (GM-CSF), interleukin-6 (IL-6), stem cell factor (SCF) and macrophage-inhibition factor-alpha (MIP-1-alpha) during the transplant procedure were similar whether or not accessory cells were given. The G-CSF and IL-6 levels rose between days 5 and 14 post transplantation to approximately 1 ng/ml and 50 pg/ml respectively. This study indicates that accessory cells reinfused with PBSC collections are not responsible for the subsequent cytokine profile or rapid haematological recovery.

Exploring music intervention with restrained patients

Roy's Adaptation Model is used in a case study approach to begin examining the potential of music intervention in hospitalized, restrained patients. Restraints were removed during the time in which the patient listened to a musical tape through a headset. Mr. D, presented in this case study, was one of the 30 medical-surgical patients who participated. His observable positive behaviors increased from 10 during the preintervention period to 12 during the musical intervention. Mr. D displayed no negative behaviors during the entire study period.

The effects of recombinant human granulocyte-macrophage colony stimulating factor on the neutrophil respiratory burst in the term and preterm infant when studied in whole blood

To investigate further the susceptibility to infection of newborn infants, particularly those born prematurely, we have used a "whole blood" flow cytometric assay to compare the respiratory burst activity in recombinant human granulocyte-macrophage colony stimulating factor "primed" neutrophils obtained from healthy adults, term infants, and preterm newborn infants. The use of whole blood avoids prior cell separation procedures that may cause artifactual activation or priming. In healthy adults (n = 21), the bacterial cell wall peptide N-formyl-methionyl-leucyl-phenylalanine induced little neutrophil respiratory burst activity, suggesting that the circulating cell is relatively quiescent. Prior exposure to recombinant human granulocyte-macrophage colony stimulating factor augmented the median N-formyl-methionyl-leucyl-phenylalanine response by 425%. In cord blood from full-term neonates (n = 9), recombinant human granulocyte-macrophage colony stimulating factor produced less enhancement of the N-formyl-methionyl-leucyl-phenylalanine response (345%), but the absolute level of respiratory burst activity was at least as great as in adults, suggesting that the neutrophils are fully functional and partially primed after delivery. In preterm infants receiving intensive care (n = 10), the degree of priming was similar to that in neutrophils from term infants (344%), although the absolute level of respiratory burst activity was reduced (p = 0.0003). In response to stimulation with phorbol ester, 73.5% (18-99%) (median and range) of neutrophils obtained from adults and 77.6% (50-92%) from term babies exhibit respiratory burst activity detectable in the whole blood assay. However, in neutrophils obtained from preterm infants, there was a significant reduction in the phorbol ester-induced respiratory burst, with only 32.9% (21-61%) of cells responding (p = 0.0129).

The formation of human synovial joint cavities: a possible role for hyaluronan and CD44 in altered interzone cohesion

During fetal development, cavitation occurs within the primitive skeleton along planes destined to become the articular surfaces of synovial joints. A histochemical study of human fetal limbs was undertaken to identify the cell types involved in this cavitation and the possible role of interactions between cells and extracellular matrix. Cryostat sections were stained with antibodies to CD68, factor VIII related antigen, prolyl hydroxylase, beta 1 integrin, VCAM-1, proliferating cell nuclear antigen, chondroitin-4 sulphate, chondroitin-6-sulphate, hyaluronan synthase and CD44. Similar sections were reacted for uridine diphosphoglucose dehydrogenase (UDPGD) and acid phosphatase activity. Hyaluronan was demonstrated using an aggrecan core protein hyaluronan binding region probe. Macrophages were present prior to cavitation in the periphery of joint interzones but not at the presumptive joint line in the central interzone. Fibroblastic cells were present throughout. Absence of local VCAM-1 expression indicated that cavitation was temporally distinct from full fibroblast-like synoviocyte differentiation. CD44 was expressed by interzone cells at all stages. Staining for hyaluronan and hyaluronan synthase, but not chondroitin sulphates was present in the interzone before and at the time of cavitation. UDPGD activity was increased in a narrow band of cells at the presumptive joint line prior to cavitation. These findings suggest that joint cavitation is dependent on the behaviour of fibroblastic cells and/or adjacent chondrocytes, rather than macrophages. Since UDPGD activity is involved in hyaluronan synthesis, it is proposed that joint cavitation is facilitated by a rise in local hyaluronan concentration in an area of tissue where cohesion is dependent on the interaction between cellular CD44 and extracellular hyaluronan. As proposed by Toole et al. (1984) such a local rise in hyaluronan concentration may lead to a switch from intercellular cohesion to dissociation, leading to tissue cavitation.

Development of a simplified single-apheresis approach for peripheral-blood progenitor-cell transplantation in previously treated patients with lymphoma

PURPOSE

The aims of this study were to develop a simplified, safe, and cost-effective peripheral-blood progenitor-cell (PBPC) mobilization protocol.

PATIENTS AND METHODS

Twenty-six patients with relapsed or resistant lymphomas were entered onto a sequential cohort study in which schedules of various granulocyte colony-stimulating factor (G-CSF) were administered after cyclophosphamide 1.5 g/m2. Hematologic recovery after high-dose carmustine (BCNU) etoposide, cytarabine, and melphalan (BEAM) chemotherapy was compared with that of 46 patients who received autologous bone marrow transplantation (ABMT) without growth factors and 28 patients who received ABMT followed by G-CSF.

RESULTS

When G-CSF (10 micrograms/kg/d) was administered from the day after the cyclophosphamide, neutropenia developed on day 8 followed by an abrupt increase in the WBC count. The optimal time for PBPC harvesting was the day on which the postnadir WBC count was greater than 8.0 x 10(9)/L, as shown by CD34+ cell counts and granulocytic-macrophage colony-forming cell (GM-CFC) assays. The reproducibility of the response was such that routine monitoring of CD34+ cell counts and GM-CFC was not necessary. A single leukapheresis on this day was adequate for prompt hematologic engraftment, and posttransplant G-CSF made little further impact on the rapid recovery. Compared with both control groups, the use of PBPC led to more rapid neutrophil recovery, markedly accelerated platelet recovery, less use of antimicrobial agents and parenteral nutrition, and more than 10 days earlier discharge from hospital. All of these differences were highly significant (P < .01).

CONCLUSION

A simplified mobilization protocol is described that requires only one apheresis to achieve rapid hematologic engraftment.

The effects of gestation on circulating progenitor cells

The frequency of BFU-E in second-trimester fetal blood (484 +/- 104/10(5)) falls progressively during gestation to a value of 69 +/- 41/10(5) in cord bloods of 36 weeks gestation and beyond, but this is still significantly greater than adult blood values of 14 +/- 8 (P < 0.01). BFU-E obtained from unfractionated peripheral blood mononuclear cells from fetuses/neonates less than 36 weeks gestation were more sensitive to erythropoietin than adult BFU-E, but the sensitivity of highly purified BFU-E obtained from second-trimester fetal liver was similar to that in adult cells. Almost maximal growth of BFU-E from purified fetal progenitor cells could be achieved with erythropoietin alone, whereas adult cells required the presence of other factors with 'burst-promoting activity'.

Expression and dynamic modulation of the human granulocyte colony-stimulating factor receptor in immature and differentiated myeloid cells

In this study we have examined the expression and modulation of the human granulocyte colony-stimulating factor (G-CSF) receptor (R) in immature and differentiated myeloid cells using a 125I labelled human G-CSF analogue (TG50). Equilibrium binding data revealed a single affinity class of receptor on all cell types expressing G-CSFR (KD 235-606 pM) with neutrophils expressing 2883 +/- 672 Rs/cell. Rapid internalization of surface receptor-bound ligand at 37 degrees C was detected in both immature cells (U937) and neutrophils with > 70% of specifically bound ligand internalized within 5 min. Concentration-response data showed that the level of occupancy of neutrophil G-CSFRs by ligand at 37 degrees C was approximately 5-fold greater than predicted by equilibrium binding data and correlated closely with concentration-response data for biological activity. Re-expression of G-CSFRs following down-regulation by internalization was not detected. Down-regulation of the neutrophil G-CSFR by several agents including granulocyte-macrophage colony-stimulating factor (GM-CSF), tumour necrosis factor (TNF), lipopolysaccharide (LPS), f-met-leu-phe (fMLP), phorbol ester (TPA) and C5a was observed at 37 degrees C but not at 4 degrees C. In contrast, G-CSFRs on immature myeloid cells were significantly down-regulated by TPA only. Differentiation of myeloid leukaemic cell line HL-60 with DMSO, a frequently used model of granulocytic differentiation, was associated with a significant reduction in G-CSFR expression (11 +/- 5% of control) whereas treatment with retinoic acid led to increased G-CSFR expression (161 +/- 3%).