IRF5 regulates airway macrophage metabolic responses.

Interferon regulatory factor 5 (IRF5) is a master regulator of macrophage phenotype and a key transcription factor involved in expression of proinflammatory cytokine responses to microbial and viral infection. Here, we show that IRF5 controls cellular and metabolic responses. By integrating ChIP sequencing (ChIP-Seq) and assay for transposase-accessible chromatin using sequencing (ATAC)-seq data sets, we found that IRF5 directly regulates metabolic genes such as hexokinase-2 (Hk2). The interaction of IRF5 and metabolic genes had a functional consequence, as Irf5-/- airway macrophages but not bone marrow-derived macrophages (BMDMs) were characterized by a quiescent metabolic phenotype at baseline and had reduced ability to utilize oxidative phosphorylation after Toll-like receptor (TLR)-3 activation, in comparison to controls, ex vivo. In a murine model of influenza infection, IRF5 deficiency had no effect on viral load in comparison to wild-type controls but controlled metabolic responses to viral infection, as IRF5 deficiency led to reduced expression of Sirt6 and Hk2. Together, our data indicate that IRF5 is a key component of AM metabolic responses following influenza infection and TLR-3 activation.

Anaphylactic responses to histamine in mice utilize both histamine receptors 1 and 2.

BACKGROUND: Anaphylaxis is a severe, potentially life-threatening reaction that can occur in response to common triggers, including food allergens (e.g., peanut), insect stings, and several medications. Activation of mast cells and basophils to release preformed mediators, such as histamine, is thought to be an important process that underlies reactions. Histamine can exert effects through four different receptors, termed H1R-H4R. Despite clinical use of both H1R and H2R blockers in the therapy for acute allergic reactions, there is little mechanistic evidence to support the necessity for blocking H2R, a receptor best characterized for its role in stomach acid production. METHODS: Here, we sought to define the necessity for histamine receptors in the pathology of anaphylaxis using H1R and H2R knockout (KO) mice, as well as a H1R/H2R double KO strain. RESULTS: In response to IgE-mediated systemic anaphylaxis, the symptoms and decreases in core body temperature observed in wild-type mice were reduced but not ablated in either H1R or H2R KO. In contrast, H1R/H2R KO were significantly protected and were indistinguishable from histamine-deficient mice. Intravenous injection of histamine was sufficient to elicit these responses, and similar to IgE-mediated anaphylaxis, loss of both H1R and H2R was necessary for complete protection. CONCLUSION: Our data demonstrate definitively that both H1R and H2R participate in the immediate systemic responses during histamine-associated pathophysiology and mechanistically support the utility of H2R-blocking therapeutics in alleviating symptoms of anaphylaxis.

The relationship between experience and mental workload in anaesthetic practice: an observational study.

Mental workload is seen as a key factor in defining performance and expertise in some complex work environments, but there are no validated instruments for assessing mental workload in anaesthesia. We studied the mental workload of 20 anaesthetists of varying levels of experience, during five routine cases each, by measuring the delay in their responses to a frequently, but randomly, administered vibrotactile stimulus as a secondary task. We delivered, and recorded response times for, 6096 stimuli, with a median (range) of 55.5 (9-178) responses per case. Subjects learnt rapidly to respond to the device and there was no evidence of a 'learning curve' that might bias our results. There was limited evidence of a relationship between workload and experience; for instance, in trainees completing simple cases, mental workload had a negative linear relationship with training grade (rho = -0.360, p = 0.006). However, average differences between trainees and qualified practitioners in response times to the stimulus were overshadowed by differences between subjects at the same level of experience. Finally, although the number of 'hands full' responses was small, removing these from the analysis had a greater effect than expected, suggesting that the 'hands full' condition is not random, but varies with experience and may be independently associated with expertise. This method appears feasible for use in clinical practice and may, with refinement, aid the identification and tracking of the development of expertise in anaesthetic trainees.

Clinical evaluation of a dioic acid-based formulation on facial skin in an Indian population.

The aim of this work was to investigate the effects of 1,18-octadecen-9-dioic acid (dioic acid) and a Rumex occidentalis extract complex for their skin-lightening action in an Indian population. Prior to the clinical study, the efficacy of dioic as an inhibitor of melanogenesis was confirmed on dark-pigmented human melanocytes. As part of a 12-week vehicle-controlled clinical study, the skin-lightening effect of a test product containing 1% dioic acid, 2% of a Rumex occidentalis extract and sunscreens (SPF 15) was assessed on the facial skin of 71 Indian female volunteers. Change in skin colour was monitored by (A) Chroma Meter® measurement (L*, a*, b*) and Individual Typology Angle (ITA˚) calculation and (B) Visual grading of standardized photographs by a dermatologist. Colorimetric measurements on volunteers' cheeks showed a significant increase of L* and ITA˚ compared to baseline after 4, 8 and 12 weeks of test product application. For both L* and ITA˚ measurements, changes were significantly different than the SPF 15-containing vehicle at weeks 4 and 12. These results were confirmed by the dermatological visual grading. The overall skin-lightening action of the test product was beyond the one observed with the SPF 15 vehicle. These findings show that a dioic acid and Rumex occidentalis complex deliver a significant skin-lightening effect on facial skin in an Indian population.

Novel method of measuring the mental workload of anaesthetists during clinical practice.

BACKGROUND: Cognitive overload has been recognized as a significant cause of error in industries such as aviation and measuring mental workload has become a key method of improving safety. The aim of this study was to pilot the use of a new method of measuring mental workload in the operating theatre using a previously published methodology. METHODS: The mental workload of the anaesthetists was assessed by measuring their response times to a wireless vibrotactile device and the NASA TLX subjective workload score during routine surgical procedures. Primary task workload was inferred from the phase of anaesthesia. RESULTS: Significantly increased response time was associated with the induction phase of anaesthesia compared with maintenance/emergence, non-consultant grade, and during more complex cases. Increased response was also associated with self-reported mental load, physical load, and frustration. These findings are consistent with periods of increased mental workload and with the findings of other studies using similar techniques. CONCLUSIONS: These findings confirm the importance of mental workload to the performance of anaesthetists and suggest that increased mental workload is likely to be a common problem in clinical practice. Although further studies are required, the method described may be useful for the measurement of the mental workload of anaesthetists.

Validation of a novel fibreoptic intubation trainer.

The aim of this study was to validate a novel inexpensive training device as a means of improving the psychomotor skills involved in the manipulation of a fibreoptic endoscope. Seventy-five subjects attempted to pass a fibreoptic endoscope through the device five times, with each attempt timed to the nearest second. Although prior clinical experience of fibreoptic intubation was associated with better performance, all groups showed improvement with each attempt. Qualitative feedback indicated that the device required subjects to use similar skills to those used in clinical practice. This study supports the use of such a device in training and assessment although further studies will be required to determine whether the skills learned on the device can be transferred to the clinical environment.

Bioengineering and subjective approaches to the clinical evaluation of dry skin.

Dry skin (also known as xerosis) is a cutaneous reaction pattern indicative of abnormal desquamation, which has not only cosmetic considerations, but can also lead to the penetration of irritants and allergens through the stratum corneum (SC). Over the last few decades, our understanding of the structure, composition, formation and function of the SC has advanced tremendously; however, despite these advancements, the occurrence of dry skin remains prevalent in the adult population. The clinical evaluation of dry skin is therefore of significant importance to the cosmetic industry not only for understanding the condition but also for measuring the effects of treatment. Traditionally, dry skin has been evaluated by visual inspection, however, recently a variety of bioengineering techniques have emerged enabling the investigator to objectively assess the extent of xerotic conditions. The most frequently employed methods for the evaluation of dry skin are discussed in this review, including regression testing, squametry, measurement of transepidermal water loss, epidermal hydration, profilometry, confocal Raman spectroscopy, optical coherence tomography, in vivo confocal microscopy and magnetic resonance imaging.

A novel method of measuring the mental workload of anaesthetists during simulated practice.

BACKGROUND: Cognitive overload has been recognized as a significant cause of error in industries such as aviation, and measuring mental workload has become a key method of improving safety. The aim of this study was to pilot the use of a new method of measuring mental workload using a previously published study design. METHODS: Ten trainee anaesthetists were exposed to a simulated crisis, similar to that used in a previous study. The mental workload of the trainees was assessed by measuring their response times to a wireless vibrotactile device. RESULTS: Although all subjects treated the 'patient' adequately, response times increased significantly during the crisis (P=0.005). These findings are consistent with increased mental workload and with the findings of other studies using similar techniques. CONCLUSIONS: These findings confirm the importance of mental workload to the performance of anaesthetists, and suggest that raised mental workload is likely to be a common problem. Although further studies are required, the method described may provide a useful method for the measurement of the mental workload of anaesthetists.

Ketamine attenuates post-operative cognitive dysfunction after cardiac surgery.

BACKGROUND: Post-operative cognitive dysfunction (POCD) commonly occurs after cardiac surgery. Ketamine exerts neuroprotective effects after cerebral ischemia by anti-excitotoxic and anti-inflammatory mechanisms. We hypothesized that ketamine attenuates POCD in patients undergoing cardiac surgery concomitant with an anti-inflammatory effect. METHODS: Patients randomly received placebo (0.9% saline; n=26) or an i.v. bolus of ketamine (0.5 mg/kg; n=26) during anesthetic induction. Anesthesia was maintained with isoflurane and fentanyl. A nonsurgical group (n=26) was also included as control. Recent verbal and nonverbal memory and executive functions were assessed before and 1 week after surgery or a 1-week waiting period for the nonsurgical controls. Serum C-reactive protein (CRP) concentrations were determined before surgery and on the first post-operative day. RESULTS: Baseline neurocognitive and depression scores were similar in the placebo, ketamine, and nonsurgical control groups. Cognitive performance after surgery decreased by at least 2 SDs (z-score of 1.96) in 21 patients in the placebo group and only in seven patients in the ketamine group compared with the nonsurgical controls (P<0.001, Fisher's exact test). Cognitive performance was also significantly different between the placebo- and the ketamine-treated groups based on all z-scores (P<0.001, Mann-Whitney U-test). Pre-operative CRP concentrations were similar (P<0.33, Mann-Whitney U-test) in the placebo- and ketamine-treated groups. The post-operative CRP concentration was significantly (P<0.01, Mann-Whitney U-test) lower in the ketamine-treated than in the placebo-treated group. CONCLUSIONS: Ketamine attenuates POCD 1 week after cardiac surgery and this effect may be related to the anti-inflammatory action of the drug.

Selected nitrostyrene compounds demonstrate potent activity in chronic lymphocytic leukaemia cells, including those with poor prognostic markers.

The nitrostyrene scaffold was previously identified as a lead target structure for the development of effective compounds targeting Burkitt's lymphoma. The present study aimed to develop these compounds further in haematological malignancies, including chronic lymphocytic leukaemia (CLL). Cellular viability, flow cytometry and lactate dehydrogenase assays, amongst others, were used to examine the effects of nitrostyrene compounds on CLL cells, including a cell line representing disease with poor prognosis (HG­3) and in ex vivo CLL patient samples (n=14). The results demonstrated that two representative nitrostyrene compounds potently induced apoptosis in CLL cells. The pro­apoptotic effects of the compounds were found to be reactive oxygen species and caspase­dependent, and had minimal effects on the viability of normal donor peripheral blood mononuclear cells. Nitrostyrene compounds exhibited synergistic augmentation of apoptosis when combined with the phosphatidylinositol 3­kinase inhibitor idelalisib and demonstrated potent toxicity in ex vivo CLL cells, including those co­cultured with bone marrow stromal cells, making them more resistant to apoptosis (n=8). These compounds also demonstrated activity in samples from patients with poor prognostic indicators; unmutated immunoglobulin heavy chain genes, expression of CD38 and deletions in chromosomes 17p and 11q. These results suggest that this class of pharmaceutically active compounds offer potential in the treatment of CLL.

Role of low-dose, noncontrast computed tomography from integrated positron emission tomography/computed tomography in evaluating incidental 2-deoxy-2-[F-18]fluoro-D-glucose-avid colon lesions.

PURPOSE: To assess the contribution of concurrent low-dose, noncontrast CT in the assessment of the malignant potential of incidental focal 2-deoxy-2-[F-18]fluoro-D-glucose (FDG)-avid colonic lesions on positron emission tomography/computed tomography (PET/CT). PROCEDURES: Routine FDG-PET/CT scans were reviewed for identification of focal FDG-avid colon lesions, and the CT component was independently reviewed for an anatomical lesion and malignant potential based on CT criteria. Clinical, endoscopic, and histopathology follow-up was obtained. RESULTS: A total of 85/2,916 (3%) oncology FDG-PET/CT scans had incidental focal colon lesions. Clinical and/or endoscopic follow-up was available in 83/85 (98%) patients. Focal, corresponding CT lesions were found in 44/83 (53%) patients, but features of malignancy were not assessable. Of the 44 patients with a final diagnosis, 32/44 (73%) were FDG-PET/CT true positives; 5/44 (11%) were false positives; and 7/44 (16%) had inconclusive FDG-PET/CT findings. CONCLUSIONS: Concurrent low-dose, noncontrast CT improves localization, but does not provide independent information on the malignant potential of incidental focal colonic activity on FDG-PET/CT.

Prevalence of occult metastatic disease in patients undergoing 18F-FDG PET for primary diagnosis or staging of lung carcinoma and solitary pulmonary nodules.

BACKGROUND: Accurate staging of lung cancer is essential in determining the most appropriate management plan, as detection of occult metastasis can significantly alter management. AIMS: The aims of this study are to determine the prevalence of occult metastasis in patients undergoing 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography (PET) for evaluation of suspected/proven lung carcinoma and correlate pre-PET TNM stage with prevalence of metastasis. METHODS: FDG-PET, which identified patients with metastasis on institutional database, was re-evaluated by a nuclear medicine physician blinded to clinical information. The confidence level of metastasis was scored on a 5-point scale, with a score of >/=4 considered positive. RESULTS: There were 67 of 645 (10%) patients identified with suspected occult metastasis on FDG-PET. Twelve patients scoring

A critical role for IRF5 in regulating allergic airway inflammation.

Interferon regulatory factor 5 (IRF5) is a key transcription factor involved in the control of the expression of proinflammatory cytokine and responses to infection, but its role in regulating pulmonary immune responses to allergen is unknown. We used genetic ablation, adenoviral vector-driven overexpression, and adoptive transfer approaches to interrogate the role of IRF5 in pulmonary immunity and during challenge with the aeroallergen, house dust mite. Global IRF5 deficiency resulted in impaired lung function and extracellular matrix (ECM) deposition. IRF5 was also essential for effective responses to inhaled allergen, controlling airway hyperresponsiveness, mucus secretion, and eosinophilic inflammation. Adoptive transfer of IRF5-deficient alveolar macrophages into the wild-type pulmonary milieu was sufficient to drive airway hyperreactivity, at baseline or following antigen challenge. These data identify IRF5-expressing macrophages as a key component of the immune defense of the airways. Manipulation of IRF5 activity in the lung could therefore be a viable strategy for the redirection of pulmonary immune responses and, thus, the treatment of lung disorders.

Dynamic confidence during simulated clinical tasks.

OBJECTIVE: Doctors' confidence in their actions is important for clinical performance. While static confidence has been widely studied, no study has examined how confidence changes dynamically during clinical tasks. METHOD: The confidence of novice (n = 10) and experienced (n = 10) trainee anaesthetists was measured during two simulated anaesthetic crises, bradycardia (easy task) and failure to ventilate (difficult task). RESULTS: As expected, confidence was high in the novice and experienced groups in the easy task. What was surprising, however, was that confidence during the difficult task decreased for both groups, despite appropriate performance. CONCLUSIONS: Given that confidence affects performance, it is alarming that doctors who may be acting unsupervised should lose dynamic confidence so quickly. Training is needed to ensure that confidence does not decrease inappropriately during a correctly performed procedure. Whether time on task interacts with incorrect performance to produce further deficits in confidence should now be investigated.

Variation in hepatic extraction ratio with unbound drug fraction: discrimination between models of hepatic drug elimination.

Systematic examination of model-dependent predictions of changes in the hepatic extraction ratio (E), following alteration in the unbound fraction of drug in plasma (fub), should allow sensitive discrimination between the venous equilibrium model (model I) and the sinusoidal perfusion model (model II) of hepatic sinusoidal function if drugs which show high clearance of free drug are used. Analysis of experimental data from the literature confirmed the utility of this approach. Specifically, data related to diazepam (E = 0.95 at fub = 1) clearly conformed to the predictions of the sinusoidal perfusion model and differed markedly from those of the venous equilibrium model. Conversely, data for phenytoin (E = 0.69 at fub = 1) failed to discriminate between models, as predicted by our analysis. We identify a sensitive, convenient method for discrimination between current models of hepatic sinusoidal function and establish for the first time that a drug substrate (diazepam) conforms closely to the predictions of the sinusoidal perfusion model.

A noninvasive technique for monitoring lung vascular permeability in man.

Increased microvascular permeability resulting in increased plasma protein extravasation is the hallmark of acute inflammatory oedema and hence radiolabelled proteins can be used to monitor this process. The adult respiratory distress syndrome (ARDS) is characterized by acute inflammatory oedema and thus provides an ideal model for studying this type of oedema in the human lung. A noninvasive technique applicable to the intensive care unit has been developed for monitoring the pulmonary accumulation of the plasma protein transferrin. Transferrin was radiolabelled in vivo with indium-113m and its accumulation was monitored using a portable probe radiation detector. After correcting for changes in intrathoracic blood distribution, by simultaneously monitoring the accumulation of technetium-99m-labelled red blood cells, an index of plasma protein accumulation was calculated. In all patients with established ARDS (n = 10) the index values were greater than 1.0 X 10(-3) min-1 and these were clearly separate from the values of less than 0.5 X 10(-3) min-1 in all healthy volunteers (n = 5; P less than 0.001). The technique can clearly detect raised plasma protein accumulation indices in the lungs of patients with established inflammatory oedema of ARDS and hence may provide a pharmacological tool for the rapid evaluation in these conditions of the effects of drugs (like corticosteroids) which are known to modulate inflammatory oedema.

Endocyte endometrial smears in the cytodiagnosis of endometrial carcinoma.

The cytologic diagnosis of endometrial cancer using material obtained with the Endocyte endometrial sampler was assessed for 874 patients. The samples obtained were smeared directly on slides for fixation and staining; the smears were more difficult to assess than cervicovaginal smears, however, due to the presence of blood, the small size and density of the cells and the flattened three-dimensional architecture of the tissue fragments obtained. Only 8.2% of the samples were classified as inadequate; repeat sampling in some of those cases produced diagnostic material. All 12 cases of carcinoma (including one case in a woman less than 40 years of age) were diagnosed by cytology as malignant; however, the original cytologic sample in one of those cases was inadequate. For the diagnosis of benign versus malignant, cytology had a sensitivity of 92%, a specificity of 100% and predictive value of 100%. Cytology also diagnosed as suspicious the smears from 5 of 13 cases of endometrial hyperplasia and 2 of the 9 cases of endometrial polyps. The cytologic findings for benign and malignant samples are described and illustrated in detail. Relative to other endometrial sampling devices, the Endocyte is inexpensive and was easily used by the gynecologist and well tolerated by the patients, with no complications and minimal discomfort.

Development of evidence-based guidelines in midwifery and gynaecology nursing.

OBJECTIVE: To develop an effective and efficient method for basing nursing practice on research evidence. SETTING: The Royal Women's Hospital, Brisbane, Australia. METHOD: Nurses and midwives from various clinical areas were invited to participate in an evidence-based practice project. Standard procedures for retrieving relevant articles and evaluating their quality were observed. Where possible, raw data from studies with similar methods were summarised using appropriate statistical tests. FINDINGS: Several guidelines have been developed, staff involved with the project have become 'research literate' and the project is contributing to the hospital-wide quality improvement activities. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: It is possible to translate research findings into practice when small groups use systematic reviews to develop practice guidelines.

Trismus due to bilateral mandibular coronoid hyperplasia.

Bilateral mandibular coronoid hyperplasia is a rare cause of restricted mouth opening. Diagnosis of the condition prior to general anaesthetic is essential, as oral intubation may be impossible. The reported case illustrates the role of computed tomography in assessment of the disorder and effective treatment by coronoidectomy.