The value of decision tree analysis in planning anaesthetic care in obstetrics.

The use of decision tree analysis is discussed in the context of the anaesthetic and obstetric management of a young pregnant woman with joint hypermobility syndrome with a history of insensitivity to local anaesthesia and a previous difficult intubation due to a tongue tumour. The multidisciplinary clinical decision process resulted in the woman being delivered without complication by elective caesarean section under general anaesthesia after an awake fibreoptic intubation. The decision process used is reviewed and compared retrospectively to a decision tree analytical approach. The benefits and limitations of using decision tree analysis are reviewed and its application in obstetric anaesthesia is discussed.

Invasive oral aspergillosis in a patient with acute myeloid leukaemia.

Aspergillosis (a fungal infection by an organism of the Aspergillus species) of the oral cavity is an uncommon condition which most frequently occurs in immunocompromised patients, such as those with haematological malignancies. In such patients, prolonged neutropenia secondary to chemotherapeutic agents enables the spread of invasive aspergillosis, which is unaffected by anatomical barriers. Early detection and treatment of the condition is essential to avoid more serious complications, such as disseminated infection, which results in increased morbidity and mortality. This case report describes a patient with acute myeloid leukaemia who developed localized invasive Aspergillus flavus of the palate. High-dose antifungal therapy was instituted along with surgical removal of the involved tissues. Aspergillosis of the palate was successfully eradicated with no long-term ill effects from the treatment. Management of invasive aspergillosis includes early aggressive antifungal medication combined with surgical removal of the involved tissues.

Time-resolved FRET and FLIM of four-way DNA junctions.

Conformational transitions in a 4-way DNA junction when titrated with ionic solutions are studied using time-resolved fluorescence resonance energy transfer. Parameters characterising the transition in terms of critical ion concentration (c1/2) and the Hill coefficient for ion binding are obtained by fitting a simple two-state model using steady-state spectra. Data obtained from a fluorescence lifetime plate reader and analysed by fitting a single exponential to donor fluorescence lifetime decays are shown to be in good agreement with the parameters obtained from steady-state measurements. Fluorescence lifetimes, however, offer advantages, particularly in being independent of fluorophore concentration, output intensity, inhomogeneity in the excitation source and output wavelength. We demonstrate preliminary FRET-FLIM images of DNA junction solutions obtained using a picosecond gated CCD which are in agreement with results from a fluorescence lifetime plate reader. The results suggest that time-resolved FRET-FLIM is sensitive to subtle structural changes and may be useful in assays based on 4-way DNA junctions.

The stability and characteristics of a DNA Holliday junction switch.

A Holliday junction (HJ) consists of four DNA double helices, with a branch point discontinuity at the intersection of the component strands. At low ionic strength, the HJ adopts an open conformation, with four widely spaced arms, primarily due to strong electrostatic repulsion between the phosphate groups on the backbones. At high ionic strength, screening of this repulsion induces a switch to a more compact (closed) junction conformation. Fluorescent labelling with dyes placed on the HJ arms allows this conformational switch to be detected optically using fluorescence resonance energy transfer (FRET), producing a sensitive fluorescent output of the switch state. This paper presents a systematic and quantitative survey of the switch characteristics of such a labelled HJ. A short HJ (arm length 8 bp) is shown to be prone to dissociation at low switching ion concentration, whereas an HJ of arm length 12 bp is shown to be stable over all switching ion concentrations studied. The switching characteristics of this HJ have been systematically and quantitatively studied for a variety of switching ions, by measuring the required ion concentration, the sharpness of the switching transition and the fluorescent output intensity of the open and closed states. This stable HJ is shown to have favourable switch characteristics for a number of inorganic switching ions, making it a promising candidate for use in nanoscale biomolecular switch devices.

Role of leucocytes in damage to the vascular endothelium during ischaemia-reperfusion injury.

During this investigation, a model of tourniquet-induced forearm ischaemia-reperfusion injury is employed to investigate the role of leucocytes in damage to the vascular endothelium during ischaemia-reperfusion injury. Leucocyte entrapment is investigated by measuring the concentration of leucocytes in venous blood leaving the arm. Neutrophil and monocyte leucocyte subpopulations are isolated by density gradient centrifugation techniques. Cell surface expression of CD11b and the intracellular production of hydrogen peroxide are measured via flow cytometry. Plasma concentrations of elastase and von Willebrand factor (vWF) are measured using enzyme-linked immunosorbemt assay (ELISA) techniques. During ischaemia-reperfusion, there was an increase in CD11b cell surface expression on neutrophils (P=0.040) and monocytes (P=0.049), and a decrease in peripheral blood leucocytes (P=0.019). There was an increase in the intracellular production of hydrogen peroxide by leucocyte subpopulations (P=0.027 [neutrophils], P=0.091 [monocytes]) and in the plasma elastase concentration (P=0.05). There was also a trend to increasing plasma concentration of vWF (P=0.0562), which was measured as a marker of endothelial damage. Ischaemia-reperfusion results in increased adhesiveness, entrapment and activation of leucocytes. Even following a mild ischaemic insult, this leucocyte response was followed immediately by evidence of endothelial damage. These results may have important implications for understanding the development of chronic diseases that involve mild ischaemic episodes.

Homeostatic responses to caloric restriction: influence of background metabolic rate.

The biological responses to caloric restriction (CR) are generally examined in rats with elevated metabolic rates due to being housed at ambient temperatures (T(a)) below the zone of thermoneutrality. We determined the physiological and behavioral responses to 2 wk of 30-40% CR in male FBNF1 rats housed in cool (T(a) = 12 degrees C) or thermoneutral (TMN; T(a) = 30 degrees C) conditions. Rats were instrumented with telemetry devices and housed continuously in home-cage calorimeters for the entire experiment. At baseline, rats housed in cool T(a) had reduced rate of weight gain; thus a mild CR (5%) group at thermoneutrality for weight maintenance was also studied. Rats housed in cool T(a) exhibited elevated caloric intake (cool = 77 +/- 1; TMN = 54 +/- 2 kcal), oxygen consumption (Vo(2); cool = 9.9 +/- 0.1; TMN = 5.5 +/- 0.1 ml/min), mean arterial pressure (cool = 103 +/- 1; TMN = 80 +/- 2 mmHg), and heart rate (cool = 374 +/- 3; TMN = 275 +/- 4 beats/min). Cool-CR rats exhibited greater CR-induced weight loss (cool = -62 +/- 3; TMN = -42 +/- 3 g) and reductions in Vo(2) (cool = -2.6 +/- 0.1; TMN = -1.5 +/- 0.1 ml/min) but similar CR-induced reductions in heart rate (cool = -59 +/- 1; TMN= -51 +/- 7 beats/min). CR had no effect on arterial blood pressure or locomotor activity in either group. Unexpectedly, weight maintenance produced significant reductions in Vo(2) and heart rate. At thermoneutrality, a single day of refeeding effectively abolished CR-induced reductions in Vo(2) and heart rate. The results reveal that rats with low or high baseline metabolic rate exhibit comparable compensatory reductions in Vo(2) and heart rate and suggest that T(a) can be used to modulate the metabolic background on which the more prolonged effects of CR can be studied.

Long-Evans and Sprague-Dawley rats exhibit divergent responses to refeeding after caloric restriction.

Mature male Sprague-Dawley (SD) and Long-Evans (LE) rats were instrumented with telemetry transmitters for measurement of heart rate (HR) and housed in room calorimeters for assessment of food intake and oxygen consumption (Vo(2)) at standard laboratory temperatures (23 degrees C) to examine physiological responses to caloric restriction (CR; 60% of baseline ad libitum calories for 2 wk) and refeeding. Ad libitum controls had stable food intake (84-88 kcal/day) and gained weight at rates of 3-4 g/day. Groups from both strains assigned to CR exhibited similar patterns of weight loss and reductions in Vo(2) and HR. Upon refeeding, SD rats exhibited a mild, transient hyperphagic response (1 day) accompanied by sustained suppression of Vo(2) and HR that remained evident 8 days after refeeding. In contrast, LE rats exhibited sustained daily hyperphagia that persisted 8 days after refeeding and was accompanied by a complete restoration of HR and Vo(2). The lower HR and Vo(2) observed during refeeding in SD rats were not due to reduced locomotor activity. The results reveal a strain-dependent divergent response to recovery from CR. We conclude that during recovery from CR, homeostatic stimulation of appetite or suppression of energy expenditure may occur selectively to restore body weight.

Systemic cytokine levels in community-acquired pneumonia and their association with disease severity.

Pro-inflammatory and anti-inflammatory cytokines are important mediators in the host response to infection. In contrast to the pro-inflammatory cytokines little is known about anti-inflammatory cytokines in community-acquired pneumonia (CAP) and their relation to disease severity. Circulating levels of three pro-inflammatory cytokines (interleukin (IL)-1beta, IL-6 and tumour necrosis factor (TNF)-alpha) and two anti-inflammatory cytokines (IL-10, IL-1 receptor antagonist (IL-1ra)) were measured using an enzyme immunoassay on admission, day 3 and day 5 in 24 patients with CAP. The modified British Thoracic Society (BTS) prognostic rule and Acute Physiology and Chronic Health Evaluation (APACHE) II score were used to assess disease severity. IL-6, TNF-alpha, IL-10 and IL-1ra concentrations were detected in most patients on admission and decreased significantly on day 3 and day 5 in all survivors. A significant difference between the BTS high-risk and low-risk groups was only found for IL-6 (median (range) 477 pg x mL(-1) (7.6-1402 pg x mL(-1)) versus 81.6 pg x mL(-1) (0-943 pg x mL(-1)); p<0.05). IL-6 also correlated with the APACHE II scores on admission. Concentrations of anti-inflammatory cytokines were elevated on admission in community-acquired pneumonia but they did not correlate with disease severity scores.

Novel posttranslational activation of the LYS2-encoded alpha-aminoadipate reductase for biosynthesis of lysine and site-directed mutational analysis of conserved amino acid residues in the activation domain of Candida albicans.

The alpha-aminoadipate pathway for lysine biosynthesis is present only in fungi. The alpha-aminoadipate reductase (AAR) of this pathway catalyzes the conversion of alpha-aminoadipic acid to alpha-aminoadipic-delta-semialdehyde by a complex mechanism involving two gene products, Lys2p and Lys5p. The LYS2 and LYS5 genes encode, respectively, a 155-kDa inactive AAR and a 30-kDa phosphopantetheinyl transferase (PPTase) which transfers a phosphopantetheinyl group from coenzyme A (CoA) to Lys2p for the activation of Lys2p and AAR activity. In the present investigation, we have confirmed the posttranslational activation of the 150-kDa Lys2p of Candida albicans, a pathogenic yeast, in the presence of CoA and C. albicans lys2 mutant (CLD2) extract as a source of PPTase (Lys5p). The recombinant Lys2p or CLD2 mutant extract exhibited no AAR activity with or without CoA. However, the recombinant 150-kDa Lys2p, when incubated with CLD2 extract and CoA, exhibited significant AAR activity compared to that of wild-type C. albicans CAI4 extract. The PPTase in the CLD2 extract was required only for the activation of Lys2p and not for AAR reaction. Site-directed mutational analysis of G882 and S884 of the Lys2p activation domain (LGGHSI) revealed no AAR activity, indicating that these two amino acids are essential for the activation. Replacement of other amino acid residues in the domain resulted in partial or full AAR activity. These results demonstrate the posttranslational activation and the requirement of specific amino acid residues in the activation domain of the AAR of C. albicans.

Banning the "A word": where's the evidence?

BACKGROUND: It is argued that use of the term "accident" has a negative effect on prevention efforts as the term implies that such events are due to chance. AIM: To test the hypothesis that use of "injury" in place of "accident" can influence professional attitudes towards "accident/injury" prevention. SETTING: Leeds Health Authority area serving the population (n=740,000) of the city of Leeds in the Yorkshire region of England. METHOD: A randomised comparative study. Altogether 183 health visiting staff in the Leeds area were randomised (by place of work) to one of two groups. Each group received a similar postal questionnaire assessing attitudes relating to accident/injury prevention. One group received a questionnaire using only accident terminology while the other used injury terminology throughout. RESULTS: Fifty responses in the accident group were received and 39 in the injury group. Analysis by Mann-Whitney U tests showed little difference in group responses. The only significant finding was that respondents in the "accident" group were more likely to rank "accident prevention" of higher importance relative to respondents in the "injury" group (median 2, 25%-75% quartiles 1.8-4.0 compared with median 4, 25%-75% quartiles 2.0-5.0, p=0.04). However, this may have been a chance finding due to the multiple comparisons made. CONCLUSIONS: This study has shown little difference in health visitor responses when "accident" is replaced with "injury". It is possible that the effect of changing terminology is more nebulous--influencing society at large. However, it would be as well to recognise the lack of evidence and clarity relating to the terminology debate. Otherwise, there is a danger that the "injury" believers may become alienated from the "accident" diehards.

Monocytes are a rheologically heterogeneous population of cells.

The effect of increased adhesiveness and decreased deformability of leukocytes following activation can have a profound effect on flow through the microcirculation. Measurement of leukocyte deformability is therefore an important tool in the study of the pathology of vascular diseases. Although much work has been done on the rheological properties of lymphocytes and granulocytes, there is little information available on the larger mononuclear cells, the monocytes. To investigate monocyte rheology, attempts were made to purify monocytes by a variety of methods. Purified monocytes were then filtered through 5 microm polycarbonate filters, with flow profiles (change in volume with time) recorded over 300 seconds. The profiles were analysed by least squares fitting to an appropriate mathematical model. Analysis of filtration data demonstrated 3 distinct sub-populations of monocytes with differing rheological properties. Other workers have characterised monocytes into defined subsets on the basis of their size, phagocytic ability or expression of cell surface markers. The definition of monocytes into defined rheological subsets is a new and useful addition to these studies.

The impact of domestic violence on children: an adolescents' story.

The authors in this paper illustrate how growing up in a violent household impacts the emotional and psychological development of one college-aged student who confronts her father in a letter about his violent behavior as she was growing up. The Williams Assessment of Unresolved Issues (WAUI) survey instrument is briefly discussed as a tool in gathering data about violent episodes experienced by college-aged students during their childhood.

Attitudes of emergency nurses regarding patient assaults.

INTRODUCTION: The purpose of this study was to investigate the frequency of patient assaults on emergency nurses and to explore nurses' attitudes about patient assaults. METHOD: A convenience sample of ED nurses (N = 55) from 2 hospitals in the mid-south region of the United States was used. All subjects completed a 31-item questionnaire that assessed frequency of assaults and attitudes about patient assaults. RESULTS: Eighty-two percent of nurses surveyed had been assaulted during their careers. In the preceding year, 56% of nurses had been assaulted; 29% of these assaults were unreported. The majority of nurses (73%) believed that being assaulted "goes with the job." Only 2 nurses (3.6%) felt safe from the possibility of patient assault at work "all of the time." DISCUSSION: The high rate of patient assault and the subsequent underreporting of patient assault identified in our study are consistent with rates reported by other researchers. It is alarming that, although many of these other studies were conducted 10 or more years ago, the assault rates are nearly the same. Of the 45 nurses in this study who had been the victim of patient assaults, only 9 believed that reporting their assaults had been beneficial. Lack of support for nursing, whether it be from other nurses, management, the institution, or society, appears to be responsible for the vast underreporting of patient assaults. Nurses themselves are also unsure of how to proceed. Whereas 91% of the surveyed nurses stated that they believed they had a right to take legal action against an assaultive patient, only 65% stated that it was ethically appropriate and even less (33%) stated that they would actually press charges against an assaultive patient.

The lived experiences of adult female victims of child abuse.

The purpose of this study was to investigate the lived experiences of female victims of domestic violence who also identified themselves as victims of physical abuse as children. There have been numerous studies of identifying perpetrators of violence as having a history of experienced violence in the family of origin. However, few studies address the victims/survivors of domestic violence and the historical significance of abuse in the family of origin. It is estimated that greater than 50% of the victims of domestic violence were also victims of abuse as a child. The research design partially followed the qualitative ethnonursing methodology. This pilot project consisted of seven females between the ages of 37 and 58. These women were members of a long-standing support group for battered women. The Pitts-Williams Inventory was used to obtain data. The instrument contained six major research questions, with sub questions. Data analysis was done by identifying major themes that emerged. Eight themes were identified. The majority of the women identified their mother as the perpetrator. They described a continuous cluster of violence, which included several different forms of violence being used consistently in order to maintain control and foster isolations. This type of violence continued in throughout their childhood and adult life.

Examination of a rheological profile for blood using micropore filters.

Various techniques have been used to assess the flow properties of blood and blood cells in a range of clinical situations. Filtration through microfilters offers a single technique for measuring the flow properties of all cellular components of blood in one experiment but depends on an assumed ability to recognize cells that make up <10% of leucocytes. The remaining leucocytes, labelled fast leucocytes, were previously presumed to be lymphocytes and granulocytes. This study confirmed the identities of these fast leucocytes as those of lymphocytes and granulocytes in undiluted blood. The transit time for lymphocytes (1.2 s) and granulocytes (1.6 s) is close to that recorded for fast leucocytes (1.7 s). The resistance of each type of blood cell to flow through 5 microm filters was defined in this study as the product of the concentration of that cell in blood and its transit time through a pore in the filter. The total resistance to flow of healthy blood through the filter is 4.46 x 10(7) s/ml and is attributed to plasma (2.7%), red cells (25.9%), fast leucocytes (25.3%) and slow leucocytes (46.1%). In a cohort of 21 men with peripheral arterial disease the total resistance was increased to 7.82 x 10(7) s/ml and attributed to plasma (1.5%), red cells (14.5%), fast leucocytes (21.0%) and slow leucocytes (63.00%). This analysis therefore provides a single test for assessing the flow properties of all the cellular components of blood and plasma.

Utilising a defective IBV RNA for heterologous gene expression with potential prophylactic application.

Based on the natural ability of coronaviruses to undergo homologous RNA recombination, we are working to produce infectious bronchitis virus (IBV) recombinants using RNA generated from recombinant fowlpox viruses (FPV). The aim is to replace the spike (S) gene of an existing IBV vaccine strain with the S gene of a heterologous strain. CD-61 is an IBV defective RNA (D-RNA) derived from a naturally occurring IBV D-RNA (CD-91). CD-61 D-RNA is being investigated as an RNA vector for the expression of heterologous genes. T7-derived RNA transcripts of CD-61 can be replicated and passaged in the presence of helper virus, following electroporation into IBV-infected cells. CD-61 cDNA was modified by the addition of the hepatitis delta virus ribozyme plus T7 terminator downstream of the 3'UTR. This allowed the synthesis of discreet RNA transcripts. The complete cassette was cloned into an FPV transfer vector (pEFL10) for generating recombinant fowlpox viruses. FPV/CD-61 recombinants will be assessed for D-RNA production in IBV-infected cells. The luciferase reporter gene sequence has been inserted into the modified CD-61, under the control of the IBV transcription associated sequence (TAS) from gene 5. Luciferase has been successfully expressed from CD-61 in helper virus-infected cells.