Developing a multidisciplinary complex wound care service

This article will describe the development of a dedicated multidisciplinary complex/chronic wound care service. Using a recognized framework, the article will demonstrate how the needs of patients were first assessed and then addressed. The article will conclude that although more research is required, the results of this audit suggest that patients with long-standing complex/chronic wounds benefit from the care of a dedicated multidisciplinary wound care team. For the purpose of this article the term 'complex' is defined as any wound which is not progressing as expected despite the application of good quality standard wound care.

Cryopreservation of macropodid spermatozoa: new insights from the cryomicroscope

This study examined the effects of cooling and cryopreservation upon macropod spermatozoa (eastern grey kangaroo, Macropus giganteus and red-necked wallaby, Macropus rufogriseus). Sperm survival during and after freezing to -30 degrees C or 70 degrees C in minimum essential medium (MEM) + 5, 10, 20 or 30% (v/v) glycerol, MEM + 10 or 20% (v/v) ethylene glycol and MEM containing a mixture of 7.5% (v/v) glycerol + 10% (v/v) dimethylsulphoxide was examined by cryomicroscopy. The MEM/glycerol mixtures permitted better post-thaw sperm recovery than the other cryoprotectants. After freezing to -30 degrees C at 10 degrees C min(-1) in 20% glycerol, then rewarming at 20 degrees C min(-1), flagellar activity resumed in more than 50% of spermatozoa when the temperature increased into the range 5-10 degrees C. However, as the temperature increased, into the range 20-25 degrees C, motility declined rapidly so that less than 5% motile cells were seen at 35 degrees C. Spermatozoa in MEM without cryoprotectant were also examined by cryomicroscopy to evaluate changes in flagellar configuration, swimming behaviour and viability during cooling from 35 degrees C to approximately -7 degrees C, and rewarming to 35 degrees C. Cooling from 35 to 28 degrees C induced kangaroo spermatozoa to exhibit rigid principal-piece bending and non-linear motility, which was reversed by further cooling and the spermatozoa resumed their normal linear movement. Rewarming induced principal-piece bending in the range of 20-30 degrees C, but this effect was reversed by further warming. Although red-necked wallaby spermatozoa showed these effects, they also exhibited a tendency to form rosette-like clusters during rewarming, especially when the temperature reached approximately 14 degrees C. The clusters were induced when the flagellar end-pieces became anteriorly reflected, producing hook-like flagellar conformations, which then became interlinked.

Proteomic analysis of differential protein expression in primary hepatocytes induced by EGF, tumour necrosis factor alpha or the peroxisome proliferator nafenopin

Peroxisome proliferators are nongenotoxic rodent-liver carcinogens that have been shown to cause both an induction of hepatocyte proliferation and a suppression of apoptosis. Both epidermal growth factor (EGF) and the peroxisome proliferator nafenopin induce DNA replication in primary rat hepatocyte cultures, but apparently through different signalling pathways. However, both EGF and nafenopin require tumour necrosis factor alpha (TNFalpha) signalling to induce DNA replication. By examining proteins isolated from rat primary hepatocyte cultures using two-dimensional gel electrophoresis and mass spectrometry, we found that proteins showing an altered expression pattern in response to nafenopin differed from those showing altered expression in response to EGF. However, many proteins showing altered expression upon stimulation with TNFalpha were common to both the EGF and nafenopin responses. These proteome profiling experiments contribute to a better understanding of the molecular mechanisms involved in the response to peroxisome proliferators. We found 32 proteins with altered expression upon stimulation with nafenopin, including muscarinic acetylcholine receptor 3, intermediate filament vimentin and the beta subunit of the ATP synthase. These nonperoxisomal protein targets offer insights into the mechanisms of peroxisome proliferator-induced carcinogenesis in rodents and provide opportunities to identify toxicological markers to facilitate early identification of nongenotoxic carcinogens.

Follicular development in transplanted fetal and neonatal mouse ovaries is influenced by the gonadal status of the adult recipient

OBJECTIVE(S)

To investigate the pattern of follicular development in transplanted fetal and neonatal mouse ovaries in the presence or absence of the recipient's own ovaries.

DESIGN

Controlled experiment.

SETTING

Academic research laboratory, Department of Physiology, Monash University, Clayton, Australia.

INTERVENTION(S)

Mouse ovaries from 16-day-old fetuses, 3-day-old neonates, and 10-day-old neonates were transplanted under the kidney capsule of adult female mice, which either retained their own ovaries in situ or were bilaterally ovariectomized.

MAIN OUTCOME MEASURE(S)

Histologic analysis.

RESULT(S)

By 4 weeks after transplantation, fetal and neonatal ovaries transplanted to ovariectomized recipients displayed a pattern of follicular development similar to that observed in in situ adult mouse ovaries. In contrast, follicular development did not progress beyond the early antral stage in fetal and 3-day-old ovaries transplanted to recipients that retained their in situ ovaries. However, 10-day-old ovaries transplanted to recipients that retained their in situ ovaries displayed full follicular development and corpora lutea formation by 8 weeks after transplantation.

CONCLUSION(S)

Follicular development in transplanted immature ovarian tissue is influenced by the age of the donor ovary and gonadal status of the recipient. (Fertil Steril(R) 2000;74:000-00. Copyright2000 by American Society for Reproductive Medicine.)

Neuropsychological predictors of distress following traumatic brain injury

Emotional and behavioural difficulties are one of the most common difficulties following traumatic brain injury (TBI), although it is not clear which individuals with TBI become most distressed. Numerous factors contribute to adjustment following TBI, and the current study examined degree of cognitive decline as one potential contributor to distress following TBI. The relationship between cognitive functioning and distress may be conceptualized as being related to (a) an individual's absolute level of cognitive ability following TBI, or (b) relative degree of decline following TBI (i.e. the greater the decline, the greater the distress, regardless of absolute level of ability). The current study tested these hypotheses by comparing a measure of global emotional distress with measures of absolute level of neuropsychological functioning and indices of cognitive decline. In contrast to hypotheses, regression analyses indicated that estimated pre-morbid ability accounted for more variance in distress following TBI than either absolute level of functioning or indices of cognitive decline, with individuals with higher estimated pre-morbid abilities reporting lower levels of distress. Treatment implications are discussed.

Circadian rhythms in Neurospora: a new measurement, the reset zone

The authors define a new feature of a circadian rhythm, the reset zone, and point out its usefulness for predictions concerning oscillator behavior. The reset zone measures the responses of a circadian system to resetting pulses. It can be easily determined from a phase transition curve (PTC), which is simply a phase response curve (PRC) replotted as new phase versus old phase (Winfree's format). The reset zone is the range of new phases seen in such a plot and has two potentially useful characteristics: its size and its midpoint. A series of experiments with Neurospora involving temperature pulses indicated that the size of the reset zone changed in a nonlinear way in response to both the duration of 40 degrees C pulses and to the magnitude of temperature change for 3-h pulses. Other existing data are replotted to show how the reset zone size varies with growth temperature and with the period of different clock mutants. Employing exclusively reset zone data within the framework of a limit cycle displacement model, an equation is formulated that predicts the relative changes in the values of state variables of the oscillator for changes in any given environmental condition, such as temperature. Examples are also drawn from other organisms, such as hamsters, Gonyalaux, Kalanchoe, and Drosophila, illustrating the usefulness of the reset zone measurement. It can be used as a numerical scale for assessing the strength of a pulse, for comparing the relative effects of a given pulse applied to different organisms or mutants, for determining the directionality of the changes in state variables produced by various types of pulses, and possibly for measuring clock amplitude.

Quantitation of Epstein-Barr virus DNA in the blood of adult liver transplant recipients

BACKGROUND

Posttransplant lymphoproliferation is most often observed in pediatric transplant recipients who experience primary Epstein-Barr virus (EBV) infection at the time of or after transplantation. Lymphoproliferation is believed to be caused by impaired control of EBV-infected cells, which may be of recipient or donor origin. Most studies of EBV infection and lymphoproliferation have focused on the pediatric age group.

METHODS

We have undertaken a prospective study of EBV infection in adult liver transplant recipients. Sequentially collected peripheral blood lymphocytes were examined with a recently developed quantitative polymerase chain reaction assay. The assay quantitates EBV DNA genomic titre over a 5 log10 range.

RESULTS

Compared with healthy EBV seropositive people not undergoing immunosuppressive therapy, blood EBV DNA titre is elevated in patients with liver disease before transplantation. Overall, highest titres were observed during the first posttransplant month, and in the context of antilymphocyte therapy. In one patient, lymphoproliferation was associated with high titres which fell during reduction of immunosuppressive therapy. In another patient with lymphoproliferation of donor lymphocyte origin, blood EBV DNA titre was not as high.

CONCLUSIONS

EBV proliferation is seen in the context of advanced liver disease and after liver transplantation. EBV DNA quantitation is a useful tool to examine the effects of immunosuppression on EBV-associated lymphoproliferation, and may be an essential technique for programs exploring the merits of EBV adoptive immunotherapy.

Automated measurement of unsaturated iron binding capacity is an effective screening strategy for C282Y homozygous haemochromatosis

BACKGROUND

C282Y hereditary haemochromatosis is an appropriate condition for population screening. Transferrin saturation, the best screening test to date, is relatively expensive, labour intensive, and cannot be automated. Unsaturated iron binding capacity is a surrogate marker of transferrin saturation and its measurement can be automated.

AIMS

To evaluate a screening strategy for C282Y hereditary haemochromatosis in a tertiary hospital environment based on unsaturated iron binding capacity as the initial screening test.

METHODS

Measurement of unsaturated iron binding capacity was adapted to the main laboratory analyser. An unsaturated iron binding capacity of less than 30 micromol/l was identified as an appropriate decision point and 5182 consecutive subjects were screened over 28 consecutive days.

RESULTS

Of those screened, 697 had an unsaturated iron binding capacity less than 30 micromol/l. Of these, transferrin saturation was greater than 40% in 294. A total of 227 were able to be genotyped for the C282Y mutation. Nine subjects homozygous for C282Y were identified. Based on full cost recovery, affected persons were identified at a cost of Aus$2268.77 per case (approximately US$1496).

CONCLUSION

Automated measurement of unsaturated iron binding capacity enables a cost effective, large scale population screening programme for C282Y hereditary haemochromatosis to be developed.

Increased calcium influx in a monocytic cell line on exposure to ultrafine carbon black

Ultrafine particles have been shown to induce pro-inflammatory effects both in vivo and in vitro. Increased expression of pro-inflammatory genes probably requires the activation of specific transcription factors such as nuclear factor kappa B (NF-kappaB) via a number of possible pathways including Ca2+ and reactive oxygen species. The fluorescent dye fura 2, was used to measure cytosolic Ca2+ in the human monocytic cell line, Monomac 6 on exposure to 66 microg x mL(-1) of either ultrafine carbon black (ufCB; diameter 14 nm), carbon black (CB; diameter 260 nm), quartz (diameter 1.45 microm), or medium alone. UfCB but not fine CB induced a 1.6-fold increase (p<0.01) in the resting cytosolic Ca2+ concentration of Monomac 6 cells. In addition ufCB induced a 2.6-fold increase (p<0.001) in the response to the endoplasmic reticulum Ca2+- adenosine triphosphatase (ATPase) inhibitor, thapsigargin, suggesting the Ca2+ release-activated Ca2+ current across the plasma membrane was enhanced. This response was inhibited by the removal of extracellular Ca2+ and by the Ca2+ channel blocker, verapamil. In addition, ufCB stimulated the entry of extracellular Mn2+. Finally, the antioxidants mannitol and nacystelin both inhibited the effects of ufCB on the response to thapsigargin. These data suggest that ultrafine carbon black particles stimulated an increase in cytosolic Ca2+, possibly through the entry of extracellular Ca2+ via Ca2+ channels in the plasma membrane. The particles may in part activate the opening of Ca2+ channels via a mechanism involving reactive oxygen species.

Release of TNFalpha in response to SiC fibres: differential effects in rodent and human primary macrophages, and in macrophage-like cell lines

Asbestos has been implicated in the pathogenesis of several lung diseases, but its mechanism of action is not fully understood. However, asbestos-induced oxidative stress and production of inflammatory cytokines may play a significant role. TNFalpha is an inflammatory cytokine which has a central role in inflammation and fibrosis due to its ability to stimulate fibroblasts and collagen deposition. In this study, a panel of fibres designated either pathogenic or non-pathogenic in recent animal studies, were utilized. The amount of TNFalpha released after a 16-hour exposure to the panel of fibres was compared in four different cell types; two primary macrophage cell types and two cell lines. TNFalpha release by cells exposed to the panel did not equate to pathogenicity, although the most pathogenic fibre caused three out of the four cell types tested, to produce the greatest amount of TNFalpha. Primary rat cells and primary human cells behaved in a similar manner as regards to TNFalpha production; the cell lines behaved quite differently to their primary counterparts with regards to TNFalpha production in this study.

Selection of multiresistant hepatitis B virus during sequential nucleoside-analogue therapy

Hepatitis B virus (HBV) drug resistance to lamivudine is always accompanied by mutations in the viral polymerase gene at position 550, termed group 1 (M550V with L526M) or group 2 (M550I) mutations. The latter mutation has not been associated with famciclovir resistance. Thus, the addition of famciclovir to lamivudine therapy in persons with group 2 lamivudine resistance may lead to virus suppression. The effect of lamivudine/famciclovir combination therapy on HBV infection was monitored in 5 lamivudine-resistant patients by quantitative polymerase chain reaction and polymerase gene sequencing of serum virus. No patients treated with combination therapy had a decline in HBV load >1 log10. Continual evolution of the viral polymerase was detected in association with virologic resistance to both drugs. Cloning experiments identified the preexistence of these multidrug-resistant virus variants as minority species prior to addition of famciclovir therapy. HBV resistance to lamivudine monotherapy is associated with a complex mixture of variants that limit the efficacy of second-line nucleoside-analogue therapy. First-line potent combination therapy may reduce the emergence of HBV drug resistance.

Outcome of lamivudine resistant hepatitis B virus infection in the liver transplant recipient

BACKGROUND

In many transplant centres lamivudine is an important component of prophylaxis against, and treatment of, hepatitis B virus (HBV) graft infection. Drug resistant HBV species with specific polymerase mutations may emerge during lamivudine treatment.

AIMS

To examine the clinical consequences of graft infection by lamivudine resistant virus.

METHODS

The clinical course of four liver transplant patients who developed graft infection with lamivudine resistant virus was reviewed. The response of HBV infection to reduction of immunosuppression and to manipulation of antiviral therapy was assessed. For each patient, serum viral titre was measured and the viral polymerase gene was sequenced at multiple time points.

RESULTS

High serum titres were observed following emergence of the lamivudine resistant species. Wild type HBV re-emerged as the dominant serum species after lamivudine withdrawal. All patients developed liver failure, and onset of liver dysfunction was observed when resistant virus was the dominant serum species. In three patients, liver recovery was observed when immunosuppression was stopped and when alternative antivirals were given. Wild type virus appeared to respond to ganciclovir, and to reintroduction of lamivudine. For one patient, introduction of famciclovir was associated with clinical, virological, and histological response.

CONCLUSIONS

Failure of lamivudine prophylaxis may identify patients at special risk for the development of severe graft infection. Treatment of graft reinfection should include reduction of immunosuppression, and systematic exposure to alternative antivirals. Viral quantitation and genetic sequencing are essential components of therapeutic monitoring.

A study of communication in the Cardiac Surgery Intensive Care Unit and its implications for automated briefing

We present a study of the information transferred among caregivers in the context of cardiac surgery and use the study to evaluate a system, MAGIC, that we are developing for automated generation of briefings. Our framework integrates cognitive and quantitative evaluation methods and features three standards that reflect current practice in the Cardiothoracic Intensive Care Unit (CTICU). Using experimental design to compare human-generated and machine-generated briefings, we show that MAGIC's current level of performance is useful. Moreover, MAGIC could help improve information flow in the CTICU by providing a consistent set of information earlier than in current practice. The separate standards are also consistent in suggesting specific modifications that may be necessary for iterative design and further system development.

Bladder augmentation surgery--what about the malignant risk?

Augmentation cystoplasty has become a common surgical treatment for the neuropathic bladder. However, malignancy in bladder augmentations has been well-described and in time is estimated to occur in 1.3% of cases. We surveyed 36 paediatric surgeons from the UK with a special interest in paediatric urology to ascertain how many bladder augmentations were being performed in children each year and whether the surgeons were warning patients/parents of the malignant risks involved with this surgery. Over 150 bladder augmentations were being performed in the UK each year. Surgeons surveyed were concerned about the malignant risks and nearly all agreed that a Central Registry of patients with bladder augmentations should be established to keep track of developments.

Cost-efficacy modeling of functional testing with perfusion imaging to detect asymptomatic restenosis following percutaneous transluminal coronary angioplasty

The objective of this study was to perform a theoretical cost-efficacy analysis on the use of routine functional testing with perfusion imaging to identify patients with asymptomatic restenosis following percutaneous transluminal coronary angioplasty (PTCA) procedures. Approximately 50% of patients with restenosis following PTCA are asymptomatic. Routine functional testing is commonly performed at 3 to 6 months to identify these patients. The cost-efficacy associated with this strategy is unknown. Theoretical models were constructed based on assumed costs for functional testing (U.S. $1,300) and coronary angiography (U.S. $3,000). Restenosis rates were assumed to be 40%, and half of patients with restenosis were assumed to be asymptomatic. To provide a range of costs to identify a patient with asymptomatic restenosis, three scenarios were constructed based on the diagnostic test characteristics of functional testing. Sensitivity analyses were performed using a range of costs for functional testing, restenosis rates, and proportion of patients with restenosis who are asymptomatic. Depending on the diagnostic accuracy of functional testing, it costs $8,200 to $22,400 to identify an asymptomatic patient with restenosis following PTCA. The cost to identify a patient with asymptomatic restenosis varies inversely with the rates of restenosis. When restenosis rates are < 20%, the cost to identify a patient with asymptomatic restenosis exceeds $10,000. Similarly, the cost to identify a patient with asymptomatic restenosis increases when the proportion of patients with asymptomatic restenosis decreases. The cost, associated with the use of routine functional testing for the identification of asymptomatic patients with restenosis appears exorbitant. However, a formal study is warranted to determine the cost-efficacy of such a strategy. Cathet. Cardiovasc. Intervent. 48:352-356, 1999.

Immunohistochemical survey of p16INK4A expression in normal human adult and infant tissues

p16INK4A is a cell cycle inhibitor that is commonly inactivated in human tumors and tumor cell lines. Despite its importance in human neoplasia, the normal pattern of p16 expression remains largely unknown. Therefore, we analyzed the immunohistochemical localization of p16 in all human organs and demonstrated that cellular p16 expression is highly selective. In adults, proliferative endometrium, breast ductal epithelium, squamous and tubal metaplastic epithelium of the uterine cervix, esophageal squamous epithelium, salivary glands, and antral gastric glands all strongly express the protein. p16 is also widely expressed in endocrine glands, including Langerhans cells in the pancreas and anterior pituicytes and Leydig and Sertoli cells in testis. Within each tissue, however, p16 expression does not correlate with cellular proliferation or maturation. In infants, p16 staining was limited to thymic Hassall's corpuscles, occasional thymic lymphocytes, and only rare pancreatic epithelial cells. Therefore, increased expression of p16 in adult tissues, as in mouse tissues, may reflect a role of p16 in cellular senescence. Restriction of p16 expression in infants to the thymus, the only organ committed to early senescence, is also consistent with such a role. Documentation of the pattern of p16 expression in normal tissues will contribute to our understanding of the normal function of this protein and to interpretation of potentially altered p16 expression in human tumors.

8-aminoquinolines as anticoccidials - Part III

Analogues of the antimalarial pentaquine, 1, in which the nature of the side-chain on the 8-amino position was varied, were prepared and evaluated for anticoccidial activity both in vitro and in vivo. Specifically, both the inter-nitrogen distance and the nature of the terminal amino group were investigated. Novel analogues of equal or improved efficacy in vitro and in vivo to pentaquine were discovered.

Selection of hepatitis B surface "escape" mutants during passive immune prophylaxis following liver transplantation: potential impact of genetic changes on polymerase protein function

CASE REPORT

A patient is described who developed hepatitis B virus (HBV) reinfection five months following liver transplantation. Failure of hepatitis B immunoglobulin prophylaxis was associated with the emergence of mutations. HBV gene sequencing identified nucleotide substitutions associated with amino acid changes, one within the major hydrophilic region (MHR) of the HBV surface antigen at amino acid position 144 and one outside the MHR. Because of the overlapping reading frames of surface and polymerase genes, the latter surface antigen change was associated with an amino acid change in the polymerase protein. The patient developed significant allograft hepatitis and was treated with lamivudine (3TC) 100 mg daily. Rapid decline of serum HBV DNA was observed with loss of HBV e antigen and HBV surface antigen from serum. There was normalisation of liver biochemistry, and liver immunohistochemistry showed a reduction in HBV core and disappearance of HBs antigen staining.

CONCLUSION

Surface antigen encoding gene mutations associated with HBIg escape may be associated with alteration of the polymerase protein. The polymerase changes may affect sensitivity to antiviral treatment. Selection pressure on one HBV reading frame (for example, HBIg pressure on HBsAg, or nucleoside analogue pressure on polymerase protein) may alter the gene product of the overlapping frame. Such interactions are relevant to strategies employing passive immune prophylaxis and antiviral treatment.