Nice to know: impact of NICE guidelines on ketogenic diet services nationwide.

BACKGROUND: In 2012, the National Institute for Health and Care Excellence (NICE) Clinical Guidelines for Epilepsies: Diagnosis and Management (CG137) included, for the first time, ketogenic diets (KDs) as a treatment option for drug-resistant paediatric epilepsy. The recommendation was made to refer children and young people with epilepsy whose seizures have not responded to appropriate anti-epileptic drugs to a tertiary paediatric epilepsy specialist for consideration of the use of KDs. We aimed to assess the impact of this change in guidance on the numbers of ketogenic centres and patients following KDs for epilepsy in the UK and Ireland. METHODS: An online survey was circulated to ketogenic dietitians from the UK and Ireland. The results were compared with similar surveys published in 2000 and 2010. RESULTS: The number of centres offering KDs for treatment of epilepsy has risen from 22 in 2000, to 28 in 2010, and to 39 in 2017 (77% overall increase). Seven of these centres accept adult referrals, in comparison to only two centres in 2010. Patient numbers have increased from 101 in 2000 to 754 in 2017. In total, 267 patients are waiting to commence KD at 31 centres. CONCLUSIONS: Over the last 7 years, the number of patients treated with a KD for epilepsy in the UK and Ireland has increased by 647%, with a 77% increase in the number of centres offering KDs. Despite this rapid growth, there is ongoing demand for patients to be considered for dietary therapy, highlighting the need for continued expansion of KD services nationally.

Understanding the core principles of a 'modified ketogenic diet': a UK and Ireland perspective.

BACKGROUND: Many centres across the UK and Ireland anecdotally report using a 'modified ketogenic diet' (MKD) as a treatment for refractory epilepsy. Although a MKD is within the spectrum of ketogenic diets (KDs), there is little literature reporting upon its definition, use or clinical effectiveness. We aimed to understand the core principles of MKD practice and to assess whether and how the MKD differs from other KD protocols. METHODS: An online survey, designed by a consensus group of ketogenic dietitians, was circulated to 39 KD centres across the UK and Ireland. It consisted of 35 questions regarding dietetic practice when providing MKD. RESULTS: Eighteen centres completed the questionnaire: 13 paediatric, three adult and two combined centres. All dietitians based MKD 'prescriptions' on estimated total energy requirements. The average macronutrient profile was 75% fat and 5% carbohydrate, with protein ad libitum. Carbohydrate and fat targets were implemented via weighed portions (carbohydrate lists n = 18; fat lists n = 13) and 'household measures' (carbohydrate lists n = 2; fat lists n = 3). Of the centres, 94% (n = 17) adjusted macronutrients over time; these decisions were based on ketone levels and seizures in most cases (83%; n = 14). Ketogenic nutritional products available on prescription were used by 10 centres (56%) when initiating and by all centres when 'fine-tuning' the MKD. CONCLUSIONS: A modified ketogenic diet in the UK and Ireland is a hybrid KD, adopting principles from other established KD protocols and defining new elements unique to the MKD. Further research into the clinical and cost-effectiveness of MKD would be of benefit.

Motor unit activity within the depth of the masseter characterized by an adapted scanning EMG technique.

OBJECTIVE: To study motor unit activity in the medio-lateral extension of the masseter using an adapted scanning EMG technique that allows studying the territories of multiple motor units (MUs) in one scan. METHODS: We studied the m. masseter of 10 healthy volunteers in whom two scans were performed. A monopolar scanning needle and two pairs of fine-wire electrodes were inserted into the belly of the muscle. The signals of the fine wire electrodes were decomposed into the contribution of single MUs and used as a trigger for the scanning needle. In this manner multiple MU territory scans were obtained simultaneously. RESULTS: We determined 161 MU territories. The maximum number of territories obtained in one scan was 15. The median territory size was 4.0mm. Larger and smaller MU territories were found throughout the muscle. CONCLUSIONS: The presented technique showed its feasibility in obtaining multiple MU territories in one scan. MUs were active throughout the depth of the muscle. SIGNIFICANCE: The distribution of electrical and anatomical size of MUs substantiates the heterogeneous distribution of MUs throughout the muscle volume. This distributed activity may be of functional significance for the stabilization of the muscle during force generation.

Comparison of the Freelite serum free light chain (SFLC) assay with serum and urine electrophoresis/immunofixation and the N Latex FLC assay.

Few reports have compared available serum free light chain (SFLC) assays. Here, a retrospective audit of the Freelite SFLC assay compared results to electrophoresis (EP)/immunofixation (IFX) and the N Latex FLC assay.A total of 244 samples collected over 3.5 months were studied using the Freelite and N Latex FLC nephelometry assays. Results were compared with serum and/or urine EP/IFX. The precision and linearity of the N Latex FLC assay was examined.Detectable paraprotein by serum or urine EP/IFX was present in 94% of samples with kappa and 100% with lambda FLC restriction. The correlation between the assays was higher for kappa (rho = 0.97) than lambda (rho = 0.89) especially when lambda results were above the upper limit of normal (rho = 0.62). Agreement in the categorical diagnosis as measured by the Cohen's kappa statistic was good (0.70). The N Latex FLC assay displayed good precision and linearity. In discordant samples the Freelite and N Latex FLC assays had equivalent agreement with IFX.Traditional methods of EP/IFX detected paraproteins in the majority of cases. Correlation between the Freelite and N Latex FLC assay is better for kappa than lambda FLC. The two assays are not entirely equivalent. Care should be taken by interpreting physicians and laboratories considering switching assays.

Valleytronics. The valley Hall effect in MoS2 transistors.

Electrons in two-dimensional crystals with a honeycomb lattice structure possess a valley degree of freedom (DOF) in addition to charge and spin. These systems are predicted to exhibit an anomalous Hall effect whose sign depends on the valley index. Here, we report the observation of this so-called valley Hall effect (VHE). Monolayer MoS2 transistors are illuminated with circularly polarized light, which preferentially excites electrons into a specific valley, causing a finite anomalous Hall voltage whose sign is controlled by the helicity of the light. No anomalous Hall effect is observed in bilayer devices, which have crystal inversion symmetry. Our observation of the VHE opens up new possibilities for using the valley DOF as an information carrier in next-generation electronics and optoelectronics.

Accuracy assessment of CKC high-density surface EMG decomposition in biceps femoris muscle.

The aim of this study was to assess the accuracy of the convolution kernel compensation (CKC) method in decomposing high-density surface EMG (HDsEMG) signals from the pennate biceps femoris long-head muscle. Although the CKC method has already been thoroughly assessed in parallel-fibered muscles, there are several factors that could hinder its performance in pennate muscles. Namely, HDsEMG signals from pennate and parallel-fibered muscles differ considerably in terms of the number of detectable motor units (MUs) and the spatial distribution of the motor-unit action potentials (MUAPs). In this study, monopolar surface EMG signals were recorded from five normal subjects during low-force voluntary isometric contractions using a 92-channel electrode grid with 8 mm inter-electrode distances. Intramuscular EMG (iEMG) signals were recorded concurrently using monopolar needles. The HDsEMG and iEMG signals were independently decomposed into MUAP trains, and the iEMG results were verified using a rigorous a posteriori statistical analysis. HDsEMG decomposition identified from 2 to 30 MUAP trains per contraction. 3 ± 2 of these trains were also reliably detected by iEMG decomposition. The measured CKC decomposition accuracy of these common trains over a selected 10 s interval was 91.5 ± 5.8%. The other trains were not assessed. The significant factors that affected CKC decomposition accuracy were the number of HDsEMG channels that were free of technical artifact and the distinguishability of the MUAPs in the HDsEMG signal (P < 0.05). These results show that the CKC method reliably identifies at least a subset of MUAP trains in HDsEMG signals from low force contractions in pennate muscles.

Genetic diversity among Campylobacter jejuni isolates from pets in Ireland.

Campylobacter jejuni isolates obtained from pets housed in shelters and in private households were subtyped by fla typing (using DdeI and HinfI restriction enzymes) and pulsed-field gel electrophoresis (PFGE) techniques. Composite fla cluster analysis on 78 C jejuni isolates was more discriminative than either single fla typing technique with 39.7 per cent single isolate patterns. PFGE on 52 C jejuni isolates revealed 53.8 per cent single isolate patterns and was the most discriminative method applied. A database of C jejuni subtyping profiles from pets in Ireland was assembled. The presence of genetic heterogeneity detected in the C jejuni subtypes suggests that pets can acquire the organisms from multiple potential sources. In addition, heterogeneity was detected in the C jejuni subtypes obtained by different culture methods within the same pet. There was a link between isolates from dogs in close contact in the same environment, confirming that this is a potential route of infection, and clusters were detected containing both cat and dog C jejuni isolates, suggesting possible interspecies transmission.

Comparison of disc diffusion and epsilometer (E-test) testing techniques to determine antimicrobial susceptibility of Campylobacter isolates of food and human clinical origin.

The antibiotic resistance profiles of 75 Campylobacter isolates of food and human clinical origin was determined by two agar diffusion susceptibility methods; disc diffusion and epsilometer-test (E-test). The most common therapeutic antimicrobials, erythromycin, ciprofloxacin and tetracycline were studied, along with chloramphenicol, ampicillin and naladixic acid. The resistance observed for each antimicrobial, as determined by both of methods, were statistically compared using Fisher two-tailed analysis. Of the six antimicrobials studied only two were shown to have statistically different patterns when resistance was compared by disc diffusion and E-test. The percentage of isolates resistant to clinically relevant antimicrobials using both techniques ranged from 6.6 to 21.3% for erythromycin, 25.3-26.6% for tetracycline and 33.3-36.0% for ciprofloxacin. The prevalence of multi-drug resistant (MDR) campylobacters (isolates resistant to 2 or more antimicrobials) for both disc diffusion and E-test was 44%. It can be concluded that, for four of the six antimicrobials assessed, antimicrobial resistance prevalences could be equally determined by either of the methods studied.

Laparoscopic single-site surgery for placement of an adjustable gastric band: initial experience.

BACKGROUND: Laparoendoscopic single-site (LESS) surgery for cholecystectomy and appendectomy are described in the literature. The benefits of these procedures compared with traditional laparoscopic approaches have yet to be determined. To date, no series of LESS surgeries for placement of an adjustable gastric band has been published or documented. This study aimed to determine the safety and feasibility of LESS surgery for placement of an adjustable gastric band. METHODS: From December 2007 to June 2008, LESS surgery to place an adjustable gastric band via a transumbilical incision was performed for 10 patients with institutional review board approval. Essentially, multiple ports were placed through a single incision in the umbilicus to allow for liver retraction, visualization, and working instruments. All critical steps using a standard pars flaccida technique were performed without alteration. RESULTS: For this study, 10 patients (9 women and 1 man) were carefully selected. These patients ranged in age from 32 to 61 years (mean, 47 years) and had a mean body mass index (BMI) of 42 kg/m2 (range, 35-45 kg/m2). The patients were selected for absence of both hepatomegaly and central obesity. Superobese patients were not considered for inclusion in the study. The mean operative time was 1 h and 10 min (range, 53 min to 1 h and 48 min). All the patients were discharged home within 23 h of admission, and no perioperative complications were noted. In addition, no wound-related complications occurred. Notably, only 2 of the 10 patients required the use of narcotic analgesia after discharge from the recovery room. There were no intra- or postoperative complications. CONCLUSIONS: In our experience, LESS surgery for adjustable gastric banding shows this technique to be both feasible and safe for selected patients. Although technical limitations exist that will be improved upon, further studies are needed to compare LESS surgery for placement of an adjustable gastric band with traditional laparoscopic techniques.

A comparison of different culture methods for the recovery of Campylobacter species from pets.

Five culture methods for the recovery of Campylobacter species (spp.) were evaluated on 361 rectal swabs collected from cats and dogs in Ireland. Speciation using PCR methods was performed on all isolates to assess the sensitivity of each culture method for isolation of Campylobacter spp., and to establish the prevalence of Campylobacter jejuni, C. coli, C. upsaliensis, C. lari and C. helveticus. Overall 163 of 361 (45.2%) samples were confirmed Campylobacter spp. positive. Direct plating onto modified charcoal cefoperazone deoxycholate agar (mCCDA) with cefoperazone, amphotericin and teicoplanin (CAT) selective supplement yielded a significantly higher prevalence of Campylobacter spp. (33.0%) than each of the other four methods (P < or = 0.05). This method was also the most sensitive method for isolation of C. upsaliensis compared with any of the other four methods used in the current study (P < or = 0.05). A direct plating method onto mCCDA agar with CCDA selective supplement and a filtration method onto blood agar after pre-enrichment in CAT supplemented broth yielded lower Campylobacter spp. prevalences of 19.7% and 17.5% respectively. A filtration method onto CAT agar and pre-enrichment in Preston broth before plating onto mCCDA agar were less sensitive for the isolation of Campylobacter spp. Speciation results of Campylobacter isolates revealed the majority of Campylobacter isolates were C. upsaliensis (50.0%) and C. jejuni (41.9%). A small number of isolates were C. coli (2.6%), C. lari (1.5%) and C. helveticus (1.1%). The overall detection of Campylobacter spp. in the 361 pets sampled was significantly increased by using a combination of isolation methods (P < or = 0.05), producing a more accurate determination of the prevalence of Campylobacter spp. in pets in Ireland and of the actual Campylobacter species. As the majority of Campylobacter spp. were recovered by direct plating onto mCCDA agar with CAT supplement, this method is the method of choice if only a single method is selected for isolation of the most common Campylobacter spp. detected in pets and humans.

Prevalence of thermophilic Campylobacter species in household cats and dogs in Ireland.

Rectal swabs were collected from 147 household dogs and 35 household cats, including healthy animals, animals with gastrointestinal signs and animals with a variety of medical and surgical conditions. A combination of selective culture methods was used to optimise the recovery of Campylobacter species, and a PCR was used to confirm their isolation and to identify the species. The overall prevalence of Campylobacter species was 42.9 per cent in the cats and 41.5 per cent in the dogs. Campylobacter upsaliensis was the species most commonly isolated from the dogs and cats, and Campylobacter jejuni was the second most commonly isolated. Particularly high prevalences were detected in the few cats and dogs with diarrhoea, and in the cats and dogs that were six months old or younger.

Automatic decomposition of multichannel intramuscular EMG signals.

We describe an automatic algorithm for decomposing multichannel EMG signals into their component motor unit action potential (MUAP) trains, including signals from widely separated recording sites in which MUAPs exhibit appreciable interchannel offset and jitter. The algorithm has two phases. In the clustering phase, the distinct, recurring MUAPs in each channel are identified, the ones that correspond to the same motor units are determined by their temporal relationships, and multichannel templates are computed. In the identification stage, the MUAP discharges in the signal are identified using matched filtering and superimposition resolution techniques. The algorithm looks for the MUAPs with the largest single channel components first, using matches in one channel to guide the search in other channels, and using information from the other channels to confirm or refute each identification. For validation, the algorithm was used to decompose 10 real 6-to-8-channel EMG signals containing activity from up to 25 motor units. Comparison with expert manual decomposition showed that the algorithm identified more than 75% of the total 176 MUAP trains with an accuracy greater than 95%. The algorithm is fast, robust, and shows promise to be accurate enough to be a useful tool for decomposing multichannel signals. It is freely available at http://emglab.stanford.edu.

Antibiotic resistance of retail food and human Campylobacter isolates on the island of Ireland from 2001-2002.

The antimicrobial resistance profiles of Campylobacter isolates recovered from a range of retail food samples (n=374) and humans (n=314) to eight antimicrobial compounds were investigated. High levels of resistance in food C. jejuni isolates were observed for ceftiofur (58%), ampicillin (25%) and nalidixic acid (17%) with lower levels observed for streptomycin (7.9%) and chloramphenicol (8.3%). A total of 80% of human C. jejuni isolates were resistant to ceftiofur, while 17% showed resistance to ampicillin and nalidixic acid, 8.6% to streptomycin and 4.1% to chloramphenicol. Resistance to clinically relevant antimicrobials such as erythromycin, ciprofloxacin and tetracycline was 6.7, 12, and 15% respectively for all food isolates and was similar to corresponding resistance prevalences observed for human isolates, where 6.4, 12 and 13% respectively were found to be resistant. Comparisons of C. jejuni isolates in each location showed a high degree of similarity although some regional variations did exist. Comparison of total C. jejuni and C. coli populations showed minor differences, with C. jejuni isolates more resistant to ampicillin and ceftiofur. Multidrug resistance patterns showed some profiles common to human and clinical isolates.

Prevalence of thermophilic Campylobacter species in cats and dogs in two animal shelters in Ireland.

Rectal swabs or faecal samples for the isolation of Campylobacter species were taken from 120 dogs and cats in an animal shelter in which only one kitten showed signs of gastrointestinal disease, and rectal swabs were taken from 46 dogs, 22 of which showed signs of gastrointestinal disease, in another shelter. At the first shelter, the swabs from 24 of 47 dogs (51.1 per cent) and 36 of 48 cats (75 per cent) yielded a Campylobacter species. The rate of isolation was significantly higher from dogs and cats less than six months old, and significantly higher from cats than from dogs (P< or =0.05). At the second shelter Campylobacter species were isolated from 40 of 46 dogs (87 per cent), but there was no significant difference between the age groups. Campylobacter species were isolated from 19 (86.4 per cent) of the 22 dogs with signs of gastrointestinal disease and from 21 (87.5 per cent) of the 24 unaffected dogs. Several culture methods were applied to the samples collected from both shelters, and the combination significantly increased the recovery of Campylobacter species.

Diagnosis of Mycobacterium bovis infection in cattle by use of the gamma-interferon (Bovigam) assay.

The strategic use of the gamma-interferon (IFN-gamma) assay (Bovigam) can provide a means for the early identification of Mycobacterium bovis infected cattle, thus ensuring their removal from an infected herd. When used in parallel with the tuberculin test, it is capable of identifying infected cattle, which might otherwise not be detected until later, if at all. The early detection and removal of these animals reduces the risk that they will become a source of infection for other cattle. When targeted in herds of high prevalence the benefits to the herd owner directly concerned can be considerable as the assay provides a means of shortening the period of restriction for such herds. This serves to generate confidence among herd owners and other stakeholders that effective schemes, based on sound scientific principles, can be developed to eradicate tuberculosis from infected cattle populations.

The effect of the tuberculin test and the consequences of a delay in blood culture on the sensitivity of a gamma-interferon assay for the detection of Mycobacterium bovis infection in cattle.

The strategic use of the gamma-interferon (IFN-gamma) assay (Bovigam) can provide a means for the early identification of Mycobacterium bovis infected cattle, thus ensuring their removal from an infected herd. It has been reported that performance of the test can be influenced by various factors including a recent tuberculin skin test and the length of delay between collection and processing of blood samples. In this study, single intradermal comparative tuberculin test (SICTT) reactor and non-reactor cattle were recruited from herds infected with M. bovis and grouped according to their SICTT responses. Group 1 comprised reactor cattle selected on the basis of their SICTT response to PPD-bovine (purified protein derivative of tuberculin) exceeding that of PPD-avian by at least 12mm. Group 2 animals were selected from herds undergoing routine surveillance for bovine tuberculosis and contained standard SICTT reactor cattle (PPD-bovine exceeding that of PPD-avian by at least 4mm) and non-reactors. We investigated the effects of the SICTT on the assay results by measuring the in vitro IFN-gamma responses of Group 1 reactor cattle at time intervals pre- and post-skin test. No significant differences were measured in the IFN-gamma responses of the reactor animals to PPD-bovine and PPD-avian for up to 65 days. To investigate if a delay in processing of blood affected the performance of the assay, we compared results using duplicate blood samples from Group 1 and Group 2 cattle stimulated with PPD antigen at 8h and at 24h after collection. In both groups of animals the mean optical density (OD) values of the assay at 24h post-collection were significantly lower than those at 8h. Our results demonstrated that a delay in processing of the blood samples from cattle subjected to routine surveillance could significantly impact on the outcome of the IFN-gamma assay resulting in a change of the IFN-gamma status of the animals.

Surface electromyogram signal modelling.

The paper reviews the fundamental components of stochastic and motor-unit-based models of the surface electromyogram (SEMG). Stochastic models used in ergonomics and kinesiology consider the SEMG to be a stochastic process whose amplitude is related to the level of muscle activation and whose power spectral density reflects muscle conduction velocity. Motor-unit-based models for describing the spatio-temporal distribution of individual motor-unit action potentials throughout the limb are quite robust, making it possible to extract precise information about motor-unit architecture from SEMG signals recorded by multi-electrode arrays. Motor-unit-based models have not yet been proven as successful, however, for extracting information about recruitment and firing rates throughout the full range of contraction. The relationship between SEMG and force during natural dynamic movements is much too complex to model in terms of single motor units.

Occurrence of Campylobacter in retail foods in Ireland.

A surveillance study was carried out to determine the prevalence of Campylobacter in a range of retail foods purchased in three Irish cities over a 20-month period between March 2001 and October 2002. In total 2391 food samples were analysed during this period. Campylobacter was isolated from 444 raw chicken (49.9%), 33 turkey (37.5%) and 11 duck samples (45.8%). Lower isolation rates of 7/221 (3.2%), 10/197 (5.1%) and 31/262 (11.8%) were observed for raw beef, pork and lamb, respectively. One sample of pork paté from 120 samples analysed (0.8%) was Campylobacter-positive. A total of three shellfish samples (oysters) from 129 raw specimens examined (2.3%) were found to contain Campylobacter. Low prevalences of the organism (0.9%) were also isolated from fresh mushrooms. Of 62 raw bulk tank milk samples analysed, Campylobacter was recovered in a single sample (1.6%). Campylobacter was not detected in any of the comminuted pork puddings, prepared vegetables and salads, retail sandwiches or cheeses made from unpasteurised milk. In total, 543 Campylobacter were isolated from all of the food samples analysed, of which 453 (83.4%) were confirmed as Campylobacter jejuni and the remaining 90 (16.6%) as Campylobacter coli.

Campylobacter spp. in Irish feedlot cattle: a longitudinal study involving pre-harvest and harvest phases of the food chain.

The aim of this study was to investigate faecal shedding and transmission of Campylobacter spp. in cohorts of cattle within a feedlot, to assess subsequent contamination of carcasses with this pathogen and to identify risk factors associated with faecal shedding of Campylobacter spp. A cohort of 133 heifers housed in four adjacent pens was examined over a five and a half month period, from entering the feedlot to slaughter. A parallel investigation of individual rectal faecal samples and pen environmental samples were taken at monthly intervals from November to February. The entire outer and inner surfaces of a carcass side of each animal were swabbed immediately following slaughter. Campylobacter spp. were isolated from 322 (54%) of the 600 rectal faecal samples. Campylobacter jejuni and C. coli accounted for 69 and 29.7% of the isolate recovered, respectively. A total of 159 environmental samples were examined, of these Campylobacter spp. was isolated from 46 samples (29%). Campylobacter jejuni and C. coli accounted for 35 and 59% of these isolates, respectively. Campylobacter spp. was not isolated from any of the dressed carcasses. Logistic regression indicated prevalence of Campylobacter spp. faecal shedding within pens was positively correlated to the pen, the month of sampling and the Campylobacter spp. contamination status of the pen dividing bars and the water trough surface. Campylobacter spp. should be considered as a pathogen shed in the faeces of a substantial proportion of feedlot cattle. However, with good hygienic practice during harvest, a very low level of this pathogen can be achieved on dressed carcasses.

Evaluation of serum eosinophil cationic protein as a predictive marker for asthma exacerbation in patients with persistent disease.

BACKGROUND: Eosinophilic inflammation is a feature of asthma. However, serological markers to indicate eosinophil activation in this process are not fully defined. OBJECTIVE: To evaluate the relationship of serum eosinophil cationic protein (ECP) to asthma worsening and a marker for treatment effectiveness, 26 adult patients with an asthma exacerbation were identified. METHODS: Identified asthma subjects were treated with oral corticosteroids (prednisone) for 14 days. The lung function variables, forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF), were determined as percentage of predicted and the blood total eosinophil count and serum ECP levels were measured. Patients were re-evaluated after 14 days of corticosteroid treatment and then every 3 months thereafter during a 12-month period. RESULTS: Eighteen patients responded to prednisone treatment, whereas eight did not, assessed as improvement of their lung function parameters. Different serum ECP patterns could be seen in the responders compared with the non-responders. All 18 responders had considerably increased serum ECP at the time of exacerbation, whereas the non-responders had lower serum ECP levels. The serum ECP levels decreased to a greater extent in the responder patient group than in the non-responder patients following prednisone treatment. This difference in patterns was not seen with total blood eosinophil counts. CONCLUSION: Our findings suggest that serum ECP may be used to predict a response to corticosteroid therapy in adult patients with asthma.