Emergency treatment of peri-operative anaphylaxis: Resuscitation Council UK algorithm for anaesthetists

Peri-operative anaphylaxis is a rare but potentially catastrophic event which must be considered whenever unexpected and significant cardiovascular or respiratory compromise occurs during anaesthesia. The Resuscitation Council UK algorithm for peri-operative anaphylaxis highlights the importance of early intravenous adrenaline and fluid resuscitation and provides guidance on the treatment of refractory anaphylaxis and immediate follow-up. This algorithm is endorsed by the Royal College of Anaesthetists, Association of Anaesthetists, British Society of Allergy and Clinical Immunology and Clinical Immunology Professional Network of the British Society for Immunology. This document was produced by the Perioperative Allergy Network steering committee in collaboration with the Resuscitation Council UK.

Pre-existing influenza-specific nasal IgA or nasal viral infection does not affect live attenuated influenza vaccine immunogenicity in children

The United Kingdom has a national immunization programme which includes annual influenza vaccination in school-aged children, using live attenuated influenza vaccine (LAIV). LAIV is given annually, and it is unclear whether repeat administration can affect immunogenicity. Because LAIV is delivered intranasally, pre-existing local antibody might be important. In this study, we analysed banked samples from a study performed during the 2017/18 influenza season to investigate the role of pre-existing influenza-specific nasal immunoglobulin (Ig)A in children aged 6-14 years. Nasopharyngeal swabs were collected prior to LAIV immunization to measure pre-existing IgA levels and test for concurrent upper respiratory tract viral infections (URTI). Oral fluid samples were taken at baseline and 21-28 days after LAIV to measure IgG as a surrogate of immunogenicity. Antibody levels at baseline were compared with a pre-existing data set of LAIV shedding from the same individuals, measured by reverse transcription-polymerase chain reaction. There was detectable nasal IgA specific to all four strains in the vaccine at baseline. However, baseline nasal IgA did not correlate with the fold change in IgG response to the vaccine. Baseline nasal IgA also did not have an impact upon whether vaccine virus RNA was detectable after immunization. There was no difference in fold change of antibody between individuals with and without an URTI at the time of immunization. Overall, we observed no effect of pre-existing influenza-specific nasal antibody levels on immunogenicity, supporting annual immunization with LAIV in children.

The risk of Kawasaki disease after pneumococcal conjugate & meningococcal B vaccine in England: A self-controlled case-series analysis

Kawasaki disease (KD) is an uncommon condition occasionally reported after childhood vaccination. Admissions with a KD-compatible diagnosis identified from a national database in England were linked to immunisation records to investigate the risk after pneumococcal conjugate (PCV) or meningococcal B (MenB) vaccines. Both are given at 2/4/12 months of age but were introduced sequentially, allowing their effects to be separately assessed. A total of 553 linked admissions in 512 individuals were validated as KD. The relative incidence (RI) within 28 days of PCV doses 1 or 2 measured by the self-controlled case-series method was 0.62 (95% confidence interval (CI) 0.38-1.00) with a significantly decreased risk after dose 3 (RI 0.30 (95% CI 0.11-0.77)). For MenB vaccine, the RI after doses 1 or 2 was 1.03 (95% CI 0.51-2.05) and 0.64 (95% CI 0.08-5.26) after dose 3. This study shows no evidence of an increased risk of KD after either vaccine.

Differences in nasal immunoglobulin A responses to influenza vaccine strains after live attenuated influenza vaccine (LAIV) immunization in children

Different vaccine strains included in the live attenuated influenza vaccine (LAIV) have variable efficacy. The reasons for this are not clear and may include differences in immunogenicity. We report a Phase IV open-label study on the immunogenicity of a single dose of quadrivalent LAIV (Fluenz™ Tetra) in children during the 2015/16 season, to investigate the antibody responses to different strains. Eligible children were enrolled to receive LAIV; nasal samples were collected before and approximately 4 weeks after immunization. There was a significant increase in nasal immunoglobulin (Ig)A to the H3N2, B/Victoria lineage (B/Brisbane) and B/Yamagata lineage (B/Phuket) components, but not to the H1N1 component. The fold change in nasal IgA response was inversely proportional to the baseline nasal IgA titre for H1N1, H3N2 and B/Brisbane. We investigated possible associations that may explain baseline nasal IgA, including age and prior vaccination status, but found different patterns for different antigens, suggesting that the response is multi-factorial. Overall, we observed differences in immune responses to different viral strains included in the vaccine; the reasons for this require further investigation.

Logarithmic Upturn in Low-Temperature Electronic Transport as a Signature of d-Wave Order in Cuprate Superconductors

In cuprate superconductors, high magnetic fields have been used extensively to suppress superconductivity and expose the underlying normal state. Early measurements revealed insulatinglike behavior in underdoped material versus temperature T, in which resistivity increases on cooling with a puzzling log(1/T) form. We instead use microwave measurements of flux-flow resistivity in YBa_{2}Cu_{3}O_{6+y} and Tl_{2}Ba_{2}CuO_{6+δ} to study charge transport deep inside the superconducting phase, in the low-temperature and low-field regime. Here, the transition from metallic low-temperature resistivity (dρ/dT>0) to a log(1/T) upturn persists throughout the superconducting doping range, including a regime at high carrier dopings in which the field-revealed normal-state resistivity is Fermi-liquid-like. The log(1/T) form is thus likely a signature of d-wave superconducting order, and the field-revealed normal state's log(1/T) resistivity may indicate the free-flux-flow regime of a phase-disordered d-wave superconductor.

How does dose impact on the severity of food-induced allergic reactions, and can this improve risk assessment for allergenic foods?: Report from an ILSI Europe Food Allergy Task Force Expert Group and Workshop

Quantitative risk assessment (QRA) for food allergens has made considerable progress in recent years, yet acceptability of its outcomes remains stymied because of the limited extent to which it has been possible to incorporate severity as a variable. Reaction severity, particularly following accidental exposure, depends on multiple factors, related to the allergen, the host and any treatments, which might be administered. Some of these factors are plausibly still unknown. Quantitative risk assessment shows that limiting exposure through control of dose reduces the rates of reactions in allergic populations, but its impact on the relative frequency of severe reactions at different doses is unclear. Food challenge studies suggest that the relationship between dose of allergenic food and reaction severity is complex even under relatively controlled conditions. Because of these complexities, epidemiological studies provide very limited insight into this aspect of the dose-response relationship. Emerging data from single-dose challenges suggest that graded food challenges may overestimate the rate of severe reactions. It may be necessary to generate new data (such as those from single-dose challenges) to reliably identify the effect of dose on severity for use in QRA. Success will reduce uncertainty in the susceptible population and improve consumer choice.

Important and specific role for basophils in acute allergic reactions

IgE‐mediated allergic reactions involve the activation of effector cells, predominantly through the high‐affinity IgE receptor (FcεRI) on mast cells and basophils. Although the mast cell is considered the major effector cell during acute allergic reactions, more recent studies indicate a potentially important and specific role for basophils and their migration which occurs rapidly upon allergen challenge in humans undergoing anaphylaxis. We review the evidence for a role of basophils in contributing to clinical symptoms of anaphylaxis and discuss the possibility that basophil trafficking during anaphylaxis might be a pathogenic (to target organs) or protective (preventing degranulation in circulation) response. Finally, we examine the potential role of basophils in asthma exacerbations. Understanding the factors that regulate basophil trafficking and activation might lead to new diagnostic and therapeutic strategies in anaphylaxis and asthma.

Minimal impact of extensive heating of hen's egg and cow's milk in a food matrix on threshold dose-distribution curves

We analyzed reaction threshold data from 352 children undergoing open food challenges to hen's egg or cow's milk, either fresh or extensively heated into a muffin. There was no significant shift in dose-distribution curves due to the baking process, implying that existing threshold data for these allergens can be applied to allergen risk management, even when these allergens are heat-processed into baked foods.

Can we identify patients at risk of life-threatening allergic reactions to food?

Anaphylaxis has been defined as a 'severe, life-threatening generalized or systemic hypersensitivity reaction'. However, data indicate that the vast majority of food-triggered anaphylactic reactions are not life-threatening. Nonetheless, severe life-threatening reactions do occur and are unpredictable. We discuss the concepts surrounding perceptions of severe, life-threatening allergic reactions to food by different stakeholders, with particular reference to the inclusion of clinical severity as a factor in allergy and allergen risk management. We review the evidence regarding factors that might be used to identify those at most risk of severe allergic reactions to food, and the consequences of misinformation in this regard. For example, a significant proportion of food-allergic children also have asthma, yet almost none will experience a fatal food-allergic reaction; asthma is not, in itself, a strong predictor for fatal anaphylaxis. The relationship between dose of allergen exposure and symptom severity is unclear. While dose appears to be a risk factor in at least a subgroup of patients, studies report that individuals with prior anaphylaxis do not have a lower eliciting dose than those reporting previous mild reactions. It is therefore important to consider severity and sensitivity as separate factors, as a highly sensitive individual will not necessarily experience severe symptoms during an allergic reaction. We identify the knowledge gaps that need to be addressed to improve our ability to better identify those most at risk of severe food-induced allergic reactions.

Incidence of food anaphylaxis in people with food allergy: a systematic review and meta-analysis

BACKGROUND

Food allergy is a common cause of anaphylaxis, but the incidence of anaphylaxis in food allergic people is unknown.

METHODS

We undertook a systematic review and meta-analysis, using the inverse variance method. Two authors selected studies by consensus, independently extracted data and assessed study quality using the Newcastle-Ottawa assessment scale. We searched Medline, Embase, PsychInfo, CINAHL, Web of Science, LILACS and AMED between January 1946 and September 2012 and recent conference abstracts. We included registries, databases or cohort studies which described the number of food anaphylaxis cases in a defined population and time period and applied an assumed population prevalence of food allergy.

RESULTS

We included data from 34 studies. There was high heterogeneity between study results, possibly due to variation in study populations, anaphylaxis definition and data collection methods. In food allergic people, medically coded food anaphylaxis had an incidence rate of 0.14 per 100 person-years (95% CI 0.05, 0.35; range 0.01, 1.28). In sensitivity analysis using different estimated food allergy prevalence, the incidence varied from 0.11 to 0.21 per 100 person-years. At age 0-19, the incidence rate for anaphylaxis in food allergic people was 0.20 (95% CI 0.09, 0.43; range 0.01, 2.55; sensitivity analysis 0.08, 0.39). At age 0-4, an incidence rate of up to 7.00 per 100 person-years has been reported. In food allergic people, hospital admission due to food anaphylaxis had an incidence rate of 0.09 (95% CI 0.01, 0.67; range 0.02, 0.81) per 1000 person-years; 0.20 (95% CI 0.10, 0.43; range 0.04, 2.25) at age 0-19 and 0.50 (0.26, 0.93; range 0.08, 2.82) at age 0-4.

CONCLUSION

In food allergic people, the incidence of food allergic reactions which are coded as anaphylaxis by healthcare systems is low at all ages, but appears to be highest in young children.

Accuracy of three-dimensional soft tissue predictions in orthognathic surgery after Le Fort I advancement osteotomies

Prediction of postoperative facial appearance after orthognathic surgery can be used for communication, managing patients' expectations,avoiding postoperative dissatisfaction and exploring different treatment options. We have assessed the accuracy of 3dMD Vultus in predicting the final 3-dimensional soft tissue facial morphology after Le Fort I advancement osteotomy. We retrospectively studied 13 patients who were treated with a Le Fort I advancement osteotomy alone. We used routine cone-beam computed tomographic (CT) images taken immediately before and a minimum of 6 months after operation, and 3dMD Vultus to virtually reposition the preoperative maxilla and mandible in their post operative positions to generate a prediction of what the soft tissue would look like. Segmented anatomical areas of the predicted mesh were then compared with the actual soft tissue. The means of the absolute distance between the 90th percentile of the mesh points for each region were calculated, and a one-sample Student's t test was used to calculate if the difference differed significantly from 3 mm.The differences in the mean absolute distances between the actual soft tissue and the prediction were significantly below 3 mm for all segmented anatomical areas (p < 0.001), and ranged from 0.65 mm (chin) to 1.17 mm (upper lip). 3dMD Vultus produces clinically satisfactory 3-dimensional facial soft tissue predictions after Le Fort I advancement osteotomy. The mass-spring model for prediction seems to be able to predict the position of the lip and chin, but its ability to predict nasal and paranasal areas could be improved.

Dietary management of peanut and tree nut allergy: what exactly should patients avoid?

Peanut and tree nut allergies are the commonest cause of life-threatening food-allergic reactions and significantly affect quality of life in children and their families. Dietary nut avoidance and provision of emergency medication is currently the mainstay of treatment. Nut avoidance has consequences on both quality of life and nutrition. We review the terminology that may cause confusion and lead to unnecessary dietary restrictions. In peanut or tree nut-allergic children, introduction of specific nuts to which the child is not allergic may improve quality of life and should be considered in patients with multiple foods allergies, vegan or ethnic-specific diets, in whom nuts are an important source of protein. Nut-allergic consumers do not just need to avoid foods containing nuts as an ingredient, but also contend with pre-packed foods which frequently have precautionary allergen labelling (PAL) referring to possible nut contamination. Although the published rate of peanut contamination in 'snack' foods with PAL (see Box ) ranges from 0.9-32.4%, peanut contamination in non-snack items with PAL is far less common. We propose that in some peanut-allergic patients (depending on history of reactivity to trace levels of peanut, reaction severity, other medical conditions, willingness to always carry adrenaline, etc.), consideration may be given to allow the consumption of non-snack foods containing PAL following discussion with the patient's (and their family's) specialist. More work is needed to provide consumers with clearer information on the risk of potential nut contamination in pre-packed food. We also draw attention to the change in legislation in December 2014 that require mandatory disclosure of allergens in non-pre-packed foods.

Patients' ability to treat anaphylaxis using adrenaline autoinjectors: a randomized controlled trial

Background

Previous work has shown patients commonly misuse adrenaline autoinjectors (AAI). It is unclear whether this is due to inadequate training, or poor device design. We undertook a prospective randomized controlled trial to evaluate ability to administer adrenaline using different AAI devices.

Methods

We allocated mothers of food‐allergic children prescribed an AAI for the first time to Anapen or EpiPen using a computer‐generated randomization list, with optimal training according to manufacturer's instructions. After one year, participants were randomly allocated a new device (EpiPen, Anapen, new EpiPen, JEXT or Auvi‐Q), without device‐specific training. We assessed ability to deliver adrenaline using their AAI in a simulated anaphylaxis scenario six weeks and one year after initial training, and following device switch. Primary outcome was successful adrenaline administration at six weeks, assessed by an independent expert. Secondary outcomes were success at one year, success after switching device, and adverse events.

Results

We randomized 158 participants. At six weeks, 30 of 71 (42%) participants allocated to Anapen and 31 of 73 (43%) participants allocated to EpiPen were successful – RR 1.00 (95% CI 0.68–1.46). Success rates at one year were also similar, but digital injection was more common at one year with EpiPen (8/59, 14%) than Anapen (0/51, 0%, P = 0.007). When switched to a new device without specific training, success rates were higher with Auvi‐Q (26/28, 93%) than other devices (39/80, 49%; P < 0.001).

Conclusions

AAI device design is a major determinant of successful adrenaline administration. Success rates were low with several devices, but were high using the audio‐prompt device Auvi‐Q.

Skin testing with raw egg does not predict tolerance to baked egg in egg-allergic children

BACKGROUND

Most children with egg allergy tolerate egg in baked foods, such as cake, but tolerance cannot be predicted with conventional allergy testing. We hypothesized that the skin prick test (SPT) wheal to unprocessed raw egg might predict tolerance of baked egg at formal oral food challenge (OFC).

METHODS

We conducted a retrospective chart review to assess the utility of SPT wheal to egg extract (EE), raw egg (RE), and the ratio of EE:RE in predicting outcome of baked-egg OFC in children presenting to our tertiary referral centers with a physician diagnosis of egg allergy and following complete egg avoidance in their diet, between 2009 and 2013. OFC were performed following a standardized protocol using baked egg in cake, to a total dose equivalent to 3g egg protein.

RESULTS

Data were analyzed from 186 completed challenges: OFC was positive in 64 (34%) children and negative in 122 (66%). Six children experienced anaphylaxis at OFC. Children tolerant to baked egg were more likely to have a lower SPT to egg extract/raw egg and EE:RE (median 0.56) than their allergic counterparts (0.70, p < 0.05). However, ROC curve analysis demonstrated poor predictivity of challenge outcome, with AUC for SPT to egg extract, raw egg and EE:ER equal to 0.71, 0.63 and 0.60, respectively.

CONCLUSION

EE:RE was not helpful in predicting outcome of baked-egg OFC. Indeed, SPT to egg extract was slightly better at predicting outcome than either SPT to raw egg or EE:RE. Unfortunately, tolerance to baked egg can only be predicted from previous history or through controlled exposure.

Incidence of fatal food anaphylaxis in people with food allergy: a systematic review and meta-analysis

Background

Food allergy is a common cause of anaphylaxis, but the incidence of fatal food anaphylaxis is not known. The aim of this study was to estimate the incidence of fatal food anaphylaxis for people with food allergy and relate this to other mortality risks in the general population.

Methods

We undertook a systematic review and meta-analysis, using the generic inverse variance method. Two authors selected studies by consensus, independently extracted data and assessed the quality of included studies using the Newcastle-Ottawa assessment scale. We searched Medline, Embase, PsychInfo, CINAHL, Web of Science, LILACS or AMED, between January 1946 and September 2012, and recent conference abstracts. We included registries, databases or cohort studies which described the number of fatal food anaphylaxis cases in a defined population and time period and applied an assumed population prevalence rate of food allergy.

Results

We included data from 13 studies describing 240 fatal food anaphylaxis episodes over an estimated 165 million food-allergic person-years. Study quality was mixed, and there was high heterogeneity between study results, possibly due to variation in food allergy prevalence and data collection methods. In food-allergic people, fatal food anaphylaxis has an incidence rate of 1.81 per million person-years (95%CI 0.94, 3.45; range 0.63, 6.68). In sensitivity analysis with different estimated food allergy prevalence, the incidence varied from 1.35 to 2.71 per million person-years. At age 0–19, the incidence rate is 3.25 (1.73, 6.10; range 0.94, 15.75; sensitivity analysis 1.18–6.13). The incidence of fatal food anaphylaxis in food-allergic people is lower than accidental death in the general European population.

Conclusion

Fatal food anaphylaxis for a food-allergic person is rarer than accidental death in the general population.

Baked egg food challenges - clinical utility of skin test to baked egg and ovomucoid in children with egg allergy

BACKGROUND

Many children with IgE-mediated egg allergy can tolerate products containing extensively heated (baked) egg. Aside from food challenge, there are no tests which reliably predict tolerance to baked egg in egg-allergic individuals.

OBJECTIVES

To determine if skin prick test (SPT) to baked egg (muffin) and ovomucoid can predict the outcome of baked egg challenges in egg allergic patients.

METHODS

In this prospective study, children with a recent history of immediate allergic reactions to egg [and corroborative positive SPT or serum-specific IgE (ssIgE) to egg] or those with SPT/ssIgE > 95% PPV for egg allergy were invited to undergo an open standardized baked egg (muffin) challenge. SPT to egg white, ovomucoid, and fresh muffin were performed immediately prior to challenge.

RESULTS

One hundred and forty-three egg allergic children underwent baked egg challenge and of these, 90 (63%) tolerated 1 g of egg protein in a baked muffin. Of the 53 positive challenges, eight (15%) had respiratory and/or cardiovascular symptoms. The median SPT diameters in positive challenges compared with negative challenges were baked muffin - 6.0 mm/4.0 mm and ovomucoid 7.5 mm/5.0 mm respectively. Receiver operating characteristic (ROC) curves were generated for SPT to baked egg and ovomucoid. The area under the curve was 0.68 for baked egg, and 0.67 for ovomucoid. A muffin SPT of < 2 mm had a negative predictive value of 88% and an ovomucoid SPT ≥ 11 mm had a positive predictive value of 100%.

CONCLUSIONS AND CLINICAL RELEVANCE

A SPT of < 2 mm to muffin had a high negative predictive value to baked egg challenge. Ovomucoid SPT ≥ 11 mm was very likely to predict a reaction to baked egg. In these children, deferring the challenge would be appropriate.

Commentary. CT stroke window settings: an unfortunate misleading misnomer?

This commentary will discuss the use of the "stroke window" settings in the evaluation of CT head examinations and advocate their more widespread use in patients who present with neurological symptoms in addition to patients with suspected stroke. We present examples of the use of stroke windows, which revealed subtle abnormalities that were not readily apparent on default brain window settings and were subsequently confirmed on MRI or follow-up CT. As a result we suggest that stroke windows should be routine in the review of all CT head examinations.

Real time workload classification from an ambulatory wireless EEG system using hybrid EEG electrodes

This paper describes a compact, lightweight and ultra-low power ambulatory wireless EEG system based upon QUASAR's innovative noninvasive bioelectric sensor technologies. The sensors operate through hair without skin preparation or conductive gels. Mechanical isolation built into the harness permits the recording of high quality EEG data during ambulation. Advanced algorithms developed for this system permit real time classification of workload during subject motion. Measurements made using the EEG system during ambulation are presented, including results for real time classification of subject workload.

A Comparison of Shepard's Osteotome versus Trapdoor Flap Technique to Harvest Iliac Crest Bone for Secondary Alveolar Bone Grafting

Objective:

To compare the postoperative donor site morbidity and alveolar bone graft results following two different techniques for iliac crest bone graft harvest: a closed (Shepard's osteotome) and an open (trapdoor flap) technique.

Design:

A retrospective review of two cohorts of alveolar bone grafts performed from 1998 to 2004 in Birmingham Children's Hospital by two surgeons using different harvest techniques. Medical and nursing anesthetic notes and medication charts were reviewed. Alveolar bone graft results were assessed using preoperative and postoperative radiographic studies.

Patients:

A total of 137 patients underwent an operation. Of these, 109 patients were compatible with the inclusion criteria (data available, first operation, no multiple comorbidities). Sixty-four patients had iliac bone harvested using the open trapdoor technique, while 45 had the same procedure using the closed osteotomy technique.

Results:

Maximum bone graft volumes harvested were similar with both techniques. The mean length of hospital stay was 50.9 hours for the osteotome and 75.5 hours for the open technique group (p < .0001). The postoperative analgesia requirement was higher and the postoperative mobilization was delayed and more difficult for the open technique patients (p < .0005). Kindelan scores performed by two independent orthodontists were similar for both techniques.

Conclusion:

The findings demonstrate that harvesting bone from the iliac crest using an osteotome technique reduces time in hospital, analgesia requirements, and postoperative donor site morbidity with no detrimental outcome.

Superfluid density in a highly underdoped YBa_{2}Cu_{3}O_{6+y} superconductor

The superfluid density rho_{s}(T) identical with1/lambda;{2}(T) has been measured at 2.64 GHz in highly underdoped YBa_{2}Cu_{3}O_{6+y}, at 37 dopings with T_{c} between 3 and 17 K. Within limits set by the transition width DeltaT_{c} approximately 0.4 K, rho_{s}(T) shows no evidence of critical fluctuations as T-->T_{c}, with a mean-field-like transition and no indication of vortex unbinding. Instead, we propose that rho_{s} displays the behavior expected for a quantum phase transition in the (3+1)-dimensional XY universality class, with rho_{s0} proportional, variant(p-p_{c}), T_{c} proportional, variant(p-p_{c});{1/2}, and rho_{s}(T) proportional, variant(T_{c}-T);{1} as T-->T_{c}.

Transient osteoporosis of the knee

We report 12 cases of transient osteoporosis in 10 patients. The presenting symptoms, diagnostic investigations and management are considered here as well as a discussion on the aetiology and the pathology. Arthroscopic surgery was carried out in some of the patients to exclude intraarticular pathology. Resolution of symptoms occurred in all patients within 6 months and the MRI findings returned to normal.

AZD2563, a novel oxazolidinone: definition of antibacterial spectrum, assessment of bactericidal potential and the impact of miscellaneous factors on activity in vitro

AZD2563, a new oxazolidinone targeted at Gram-positive bacteria, was evaluated and compared with linezolid and other agents against 802 aerobic bacterial isolates for spectrum of activity, bactericidal activity, and the effect of miscellaneous factors upon activity in vitro. At a concentration of 2 mg/L, AZD2563 inhibited 98% of all Gram-positive bacteria tested (100% at 4 mg/L), including susceptible and resistant isolates of Staphylococcus aureus, coagulase-negative staphylococci, Enterococcus spp., Streptococcus pneumoniae, other Streptococcus spp. and Corynebacterium spp. Conversely, all Enterobacteriaceae and non-fermenting Gram-negative bacteria had MICs > 128 mg/L, and only a few Haemophilus or Moraxella spp. had MICs < 8 mg/L. By conventional laboratory definition, AZD2563 and linezolid were bacteriostatic against staphylococci and enterococci, with variable bactericidal activity against Strep. pneumoniae. The in-vitro activity of AZD2563 was essentially unaffected by altering pH, inoculum size, the type of testing medium, or the inclusion of human serum up to 25% v/v.

Observation of weak-limit quasiparticle scattering via broadband microwave spectroscopy of a d-wave superconductor

There has long been a discrepancy between microwave conductivity measurements in high temperature superconductors and the conductivity spectrum expected in the simplest models for impurity scattering in a d-wave superconductor. Here we present a new type of broadband measurement of microwave surface resistance that finally shows some of the spectral features expected for a d(x2-y2) pairing state. Cusp-shaped conductivity spectra, consistent with weak impurity scattering of nodal quasiparticles, were obtained in the 0.6-21 GHz frequency range in highly ordered crystals of YBa2Cu3O6.50 and YBa2Cu3O6.99.

The activity of meropenem and comparators against Acinetobacter strains isolated from European hospitals, 1997-2000

In vitro susceptibilities to meropenem and comparators of Acinetobacter strains isolated from serious infections in 37 European hospital centers participating in the Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program (1997-2000) were tested. There were 635 Acinetobacter strains collected: 490 A. baumannii; 51 A. calcoaceticus var. lwoffii; and 94 other Acinetobacter strains. Overall, meropenem and imipenem were the most effective agents tested. Resistance to the antimicrobials was: 14%, meropenem; 16%, imipenem; 39%, piperacillin-tazobactam; 41%, tobramycin; 45%, ceftazidime; and 53%, ciprofloxacin. Thus, the carbapenems have useful activity against Acinetobacter spp. and represent a viable choice for treating infections caused by these organisms.

Emerging antimicrobial resistances among Proteus mirabilis in Europe: report from the MYSTIC Program (1997-2001). Meropenem Yearly Susceptibility Test Information Collection

Resistance patterns that are currently problematic in Europe can vary greatly within the same species over time, among various patient populations and among geographic regions on the same continent. The results from the Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program, which monitors carbapenem resistance rates in institutions using meropenem, were used to determine resistance differences among Proteus mirabilis. MIC results from 688 P. mirabilis strains were classified into 4 patient care groups: ICU (n=426), neutropenia patients (NP; n=145), general wards (n=97) and cystic fibrosis patients (CF; n=20). A total of 40 centers from 12 European countries have participated since 1997, divided into 3 geographic regions (East, North, South). All testing was performed by NCCLS reference methods and interpretive criteria, including screening of extended-spectrum beta-lactamase (ESBL) phenotypes. Over the monitored interval the resistance rates varied for each agent without a clear trend toward a greater rate. Rank order of susceptibility was: meropenem (99%) > piperacillin/tazobactam (TAZ; 96%) > cefepime (95%) > ceftazidime (CAZ; 94%) > imipenem (IPM; 92%). Ciprofloxacin (CIP) was the least active agent tested (MIC90 4 microg/ml; 86% susceptible). Unexpectedly, 3.6% of P. mirabilis were imipenem-resistant (MIC, > or = 16 microg/ml). Greater rates of resistance were found for strains from NP and CF patients, and from eastern or southern European sites, usually associated with epidemic clusters. Generally susceptible species such as P. mirabilis have recently emerged as therapeutic problems in European medical centers following mutations that compromise CIP, CAZ and aminoglycoside use. Imipenem also showed decreased susceptibility of greater than 7% compared to less than 1% for meropenem. Continued surveillance by the MYSTIC Program appears to be a prudent practice to focus effective empiric treatment regimens.

Unit differences in pathogen occurrence arising from the MYSTIC program European database (1997-2000)

The Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) Program is a longitudinal global antimicrobial surveillance study that compares the activity of meropenem and comparator antimicrobial agents against pathogens isolated from intensive care, neutropenic or cystic fibrosis patients, and general wards. Data from the different European MYSTIC Program units (1997-2000) showed that the most prevalent isolates tested overall were methicillin-susceptible Staphylococcus aureus (MSSA; in accordance with study design methicillin-resistant S. aureus was not tested), Pseudomonas aeruginosa and Escherichia coli. In all the unit types, E. coli (approximately 20% having an extended spectrum beta-lactamase phenotype) and MSSA were highly susceptible to meropenem (97-99% susceptibility). Isolates of MSSA showed lower levels of susceptibility to ciprofloxacin (61-77% susceptibility) in both cystic fibrosis and neutropenia patients, and particularly high levels of resistance to ceftazidime (38% susceptibility) in cystic fibrosis units. Ciprofloxacin (54% susceptibility) and gentamicin (46% susceptibility) demonstrated low levels of activity against P. aeruginosa (frequently encountered in cystic fibrosis units). Meropenem and piperacillin/tazobactam were the most active agents against P. aeruginosa in all the unit types. Carbapenems and piperacillin/tazobactam have sustained > 90% susceptibility rates overall against the most frequently isolated pathogens. The analysis of specific units that house patients with a high-risk of contracting antimicrobial-resistant pathogens remains very important for the optimal selection of empiric regimens.

Speech recognition software

This article discusses the use of speech recognition software by means of reviewing two leading packages. Both programs require considerable training before they can be used effectively, but are then able to convert continuous speech into text with varying degrees of success.

Internet service providers: choosing the right one

In order to access the Internet it is necessary to open an account with an Internet Service Provider. This article describes the typical services provided by these companies so that the new subscriber will be in a better position to make an informed choice.

What, when and how to back up your data

This article defines and describes the process of backing up data files, which should be undertaken by anyone who routinely uses a computer. The important points to be considered when developing a backup strategy are explained and a résumé given of the backup devices currently available.

An evaluation of the reproducibility of landmark identification using scanned cephalometric images

OBJECTIVE

A method of cephalometric analysis is described in which cephalometric x-rays were scanned using a flat-bed scanner and transparency hood. Then the image was displayed on a computer monitor for point identification and subsequent cephalometric analysis using dedicated software. The reproducibility of point identification using this method was compared with two other, commonly used, methods.

MATERIAL AND METHODS

The study material comprised 25 lateral skull x-rays taken as part of routine orthodontic assessment. Repeat cephalometric point identification was carried out on each x-ray using 3 methods: 1. On-screen digitization of the scanned bitmap image (Screenceph method). 2. Tracing followed by digitization of the identified points and 3. Direct digitization.

RESULTS

For the 8 angular and 4 linear cephalometric measurements examined the Screenceph method compared favourably with the two conventional methods. The median difference between methods was 0.5 degrees and 0.2 mm. Using constructed Cartesian axes to examine the x, y discrepancy between repeat measurements and comparing Screenceph to tracing followed by digitization, there were significant differences in 3 instances at the 5% level and 2 instances at the 1% level. These differences represented median scores of 0.14 to 0.32 mm greater for Screenceph. Comparing Screenceph to direct digitization 15 significant differences out of the 28 measurements were noted: six at the 5% level and 9 at the 1% level. The actual difference in median scores ranged from 0.2 mm to 0.53 mm.

CONCLUSION

The results demonstrated that Screenceph is sufficiently accurate to use in a clinical setting but is not yet sufficiently exact for use in research projects owing to hardware limitations.

Unicellular cyanobacteria fix N2 in the subtropical North Pacific Ocean

Fixed nitrogen (N) often limits the growth of organisms in terrestrial and aquatic biomes, and N availability has been important in controlling the CO2 balance of modern and ancient oceans. The fixation of atmospheric dinitrogen gas (N2) to ammonia is catalysed by nitrogenase and provides a fixed N for N-limited environments. The filamentous cyanobacterium Trichodesmium has been assumed to be the predominant oceanic N2-fixing microorganism since the discovery of N2 fixation in Trichodesmium in 1961 (ref. 6). Attention has recently focused on oceanic N2 fixation because nitrogen availability is generally limiting in many oceans, and attempts to constrain the global atmosphere-ocean fluxes of CO2 are based on basin-scale N balances. Biogeochemical studies and models have suggested that total N2-fixation rates may be substantially greater than previously believed but cannot be reconciled with observed Trichodesmium abundances. It is curious that there are so few known N2-fixing microorganisms in oligotrophic oceans when it is clearly ecologically advantageous. Here we show that there are unicellular cyanobacteria in the open ocean that are expressing nitrogenase, and are abundant enough to potentially have a significant role in N dynamics.

Induction by inhibitors of nitric oxide synthase of hyperresponsiveness in the human nasal airway

1. The effects of inhibitors of nitric oxide synthase (NOS) on the responsiveness of the human nasal airway were investigated, by measuring the nasal response to histamine and bradykinin. 2. Repeated intranasal administration of N(G)-nitro-L-arginine methyl ester (L-NAME) or N(G)-monomethyl-L-arginine (L-NMMA), 1 micromol per nostril every 30 min for 6 h, increased the nasal obstruction induced by histamine, 50 - 500 microg, and bradykinin, 200 microg per nostril. A single administration of L-NAME, 1 micromol per nostril did not induce hyperresponsiveness to histamine. 3. Pretreatment with L-arginine, 30 micromol, abolished the hyperresponsiveness to histamine caused by L-NAME, 1 micromol. Pretreatment with N(G)-nitro-D-arginine methyl ester (D-NAME), 1 micromol, did not induce hyperresponsiveness to histamine. 4. Repeated administration of L-NAME, 1 micromol, caused a significant reduction in the amount of nitric oxide measured in the nasal cavity. 5. Neither L-NMMA, 1 micromol, nor L-arginine, 30 micromol, altered the nasal hyperresponsiveness induced by platelet activating factor (PAF), 60 microg. PAF did not alter the levels of nitric oxide in the nasal cavity. 6. The results suggest that inhibition of nitric oxide synthase induces a hyperresponsiveness in the human nasal airway, and that this occurs by a mechanism different from that involved in PAF-induced hyperresponsiveness.

MYSTIC (Meropenem Yearly Susceptibility Test Information Collection): a global overview

The Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) is a global, multicentre surveillance study that compares the activity of meropenem in centres that are prescribers with that of imipenem, ceftazidime, piperacillin/tazobactam, ciprofloxacin and gentamicin. Of the 46 centres (intensive care units, cystic fibrosis units, neutropenia units and general wards) contributing to this study, 29 were in Europe, 14 in the Americas and three in the Middle East and Asia. The results for the most common isolates obtained in the first year of the study from these three regions show that meropenem has a broad spectrum of activity and potency in these centres, with 89% of the 6890 strains tested having an MIC < or = 4 mg/L. The overall susceptibility was lower for the comparator antibiotics. There was evidence in all regions of strains producing beta-lactamases and other resistance mechanisms against the other beta-lactams tested, fluoroquinolones and aminoglycosides. Future years' results from this surveillance study will show whether meropenem will continue to exhibit such activity.