The Cheshire & Merseyside Collaborative trainee-led on-call service: a review of safety and efficiency.

AIM: To assess safety and efficiency of the Cheshire & Merseyside Collaborative, the largest trainee led on-call service in the UK, based on discrepancy rates and time taken to issue reports. MATERIALS & METHODS: All studies reported by the collaborative in a 4-week period were evaluated for discrepancy and the time taken to issue a report. These figures were compared against the Royal College of Radiologists (RCR) guidelines and a recent national audit of discrepancy rates. The time taken to report was measured against the National Institute of Health and Clinical Excellence (NICE) and Trauma Audit Research Network (TARN) guidelines. RESULTS: The overall discrepancy rates for the collaborative were 2.5% for minor discrepancies and 2% for major discrepancies, which is within the RCR standard. The median time taken to issue a report was 30 min, which is within the NICE and TARN 1-h targets. CONCLUSIONS: The Cheshire & Merseyside Collaborative can be deemed a safe and efficient way of delivering an out-of-hours radiology service.

The dietary form of choline during lactation affects maternal immune function in rats.

PURPOSE: The present study was designed to determine the effects of both choline form and availability on maternal immune function during lactation. METHODS: Sprague-Dawley rats were randomized to one of the three diets 24-48 h before parturition and fed ad libitum until 21 days postnatal: 1 g/kg choline as free choline (C, n = 11), the current form, and amount of choline in commercial diets; 1 g/kg choline as phosphatidylcholine (PC1, n = 11); or 2.5 g/kg choline as PC (PC2.5, n = 8). Choline metabolites in offspring stomach contents were quantified. At 21 days, lymphocytes from mothers' mesenteric lymph nodes and spleens were isolated and phenotypes and ex vivo cytokine production after mitogen exposure were determined. RESULTS: There was a higher proportion of choline and a lower proportion of lyso-PC in stomach contents (representing dam's milk) of C pups compared to PC1. In the mesenteric lymph nodes, feeding PC1 compared to C led to a higher IL-2 production after Concanavalin A (ConA) stimulation and a higher proportion of T cells (CD3+) and a lower proportion of B cells [immunoglobulin (Ig)κ, CD45RA+, and IgM+; P < 0.05]. Splenocytes from the PC1 group produced more IL-6 and TNF-α after lipopolysaccharides stimulation compared to C (P < 0.05). Splenocytes from the PC2.5 group produced more IL-2 and IL-6 after ConA stimulation compared to PC1 (P < 0.05). CONCLUSIONS: Feeding choline as PC in the maternal diet improved the ability of immune cells to respond ex vivo to mitogens and increasing the amount of PC in the diet further improved T cell proliferation.

Life history and ecology of the elusive European short-snouted seahorse Hippocampus hippocampus.

To improve the understanding of the life history and ecology of one of Europe's most elusive fishes, the short-snouted seahorse Hippocampus hippocampus, data from wild populations in a shallow coastal lagoon in southern Portugal were analysed. The data were collected from 17 tagged seahorses on a focal-study grid as well as from >350 seahorses encountered during underwater visual surveys and a fishery-independent study using beach seines. These populations of settled juveniles and adults had a mean population density of 0·009 m-2 . During the study period (2000-2004), reproduction peaked in July and August. Juveniles recruited to the lagoon at c. 66 mm standard length (LS ) and 0·5 years of age and established small home ranges (0·8 to 18·2 m2 ). First reproduction was estimated at 100 mm and 1 year of age. Based on a fitted von Bertalanffy model, H. hippocampus grew quickly (growth coefficient K = 0·93) to a maximum theoretical size L∞ = 150 mm and have a maximum lifespan of c. 3·2 years. Courtship behaviours were consistent with the maintenance of pair bonds and males brooded multiple batches of young per year. Estimated annual reproductive output averaged 871 young (±632). Together these analyses provide the first life-history parameters for this species and indicate that H. hippocampus bears characteristics of opportunist and intermediate strategists. Such populations are predicted to exhibit large fluctuations in abundance, making them vulnerable to extended periods of poor recruitment.

Feeding a diet devoid of choline to lactating rodents restricts growth and lymphocyte development in offspring.

The nutrient choline is necessary for membrane synthesis and methyl donation, with increased requirements during lactation. The majority of immune development occurs postnatally, but the importance of choline supply for immune development during this critical period is unknown. The objective of this study was to determine the importance of maternal supply of choline during suckling on immune function in their offspring among rodents. At parturition, Sprague-Dawley dams were randomised to either a choline-devoid (ChD; n 7) or choline-sufficient (ChS, 1 g/kg choline; n 10) diet with their offspring euthanised at 3 weeks of age. In a second experiment, offspring were weaned to a ChS diet until 10 weeks of age (ChD-ChS, n 5 and ChS-ChS, n 9). Splenocytes were isolated, and parameters of immune function were measured. The ChD offspring received less choline in breast milk and had lower final body and organ weight compared with ChS offspring (P<0·05), but this effect disappeared by week 10 with choline supplementation from weaning. ChD offspring had a higher proportion of T cells expressing activation markers (CD71 or CD28) and a lower proportion of total B cells (CD45RA+) and responded less to T cell stimulation (lower stimulation index and less IFN-γ production) ex vivo (P<0·05). ChD-ChS offspring had a lower proportion of total and activated CD4+ T cells, and produced less IL-6 after mitogen stimulation compared with cells from ChS-ChS (P<0·05). Our study suggests that choline is required in the suckling diet to facilitate immune development, and choline deprivation during this critical period has lasting effects on T cell function later in life.

Stoichiometric determination of moisture in edible oils by Mid-FTIR spectroscopy.

A simple and accurate method for the determination of moisture in edible oils by differential FTIR spectroscopy has been devised based on the stoichiometric reaction of the moisture in oil with toluenesulfonyl isocyanate (TSI) to produce CO2. Calibration standards were devised by gravimetrically spiking dry dioxane with water, followed by the addition of neat TSI and examination of the differential spectra relative to the dry dioxane. In the method, CO2 peak area changes are measured at 2335 cm(-1) and were shown to be related to the amount of moisture added, with any CO2 inherent to residual moisture in the dry dioxane subtracted ratioed out. CO2 volatility issues were determined to be minimal, with the overall SD of dioxane calibrations being ∼18 ppm over a range of 0-1000 ppm. Gravimetrically blended dry and water-saturated oils analysed in a similar manner produced linear CO2 responses with SD's of <15 ppm on average. One set of dry-wet blends was analysed in duplicate by FTIR and by two independent laboratories using coulometric Karl Fischer (KF) procedures. All 3 methods produced highly linear moisture relationships with SD's of 7, 16 and 28 ppm, respectively over a range of 200-1500 ppm. Although the absolute moisture values obtained by each method did not exactly coincide, each tracked the expected moisture changes proportionately. The FTIRTSI-H2O method provides a simple and accurate instrumental means of determining moisture in oils rivaling the accuracy and specificity of standard KF procedures and has the potential to be automated. It could also be applied to other hydrophobic matrices and possibly evolve into a more generalized method, if combined with polar aprotic solvent extraction.

Lysosomotropic agents selectively target chronic lymphocytic leukemia cells due to altered sphingolipid metabolism.

Lysosome membrane permeabilization (LMP) mediates cell death in a variety of cancer cells. However, little is known about lysosomes and LMP in chronic lymphocytic leukemia (CLL). Owing to drug resistance and toxicity in CLL patients, better treatment strategies are required. Our results show that CLL cells were sensitive to the lysosomotropic agent siramesine. Furthermore, this drug was more effective in CLL cells, regardless of prognostic factors, compared with normal B cells. Siramesine caused LMP, lipid peroxidation and transcription factor EB nuclear translocation followed by mitochondrial membrane potential loss and reactive oxygen species release. Siramesine-induced cell death was blocked by lipid antioxidants, but not by soluble antioxidants or protease inhibitors. To determine whether CLL cells had altered lysosomes, we investigated sphingolipid metabolism as the lysosome is a hub for lipid metabolism. We found that CLL cells had more lysosomes, increased sphingosine-1-phosphate phosphatase 1 (SPP1) expression, and increased levels of sphingosine compared with normal B cells. Raising sphingosine levels increased LMP and cell death in CLL cells, but not in normal B cells. Together, these results show that excess sphingosine in CLL cells could contribute to their sensitivity toward LMP. Thus, targeting the lysosome could be a novel therapeutic strategy in CLL.

The impact of disadvantage on the development and progression of diabetic kidney disease.

BACKGROUND: Disadvantaged people include those experiencing economic, social or educational deprivation and, in some cases, those undergoing rapid transition from subsistence to industrial economies. Disadvantaged people worldwide are affected disproportionately by the global epidemic of diabetes. They are also at increased risk of kidney disease attributable to diabetes, and for many, the cost of managing their kidney disease far exceeds their available resources. METHODS: We review factors associated with disadvantage that may increase the risk of diabetic kidney disease, and the barriers to care that hinder attempts to provide an adequate therapeutic response. RESULTS AND CONCLUSIONS: A rapidly rising prevalence and magnitude of obesity among children and adults, increasing frequency of intrauterine exposure to diabetes, and inadequate access to healthcare are responsible, in part, for a surge in the frequency of diabetes and, in turn, diabetic kidney disease among disadvantaged people. These factors may also predispose to an earlier onset of diabetes and kidney disease, thereby perpetuating the disadvantage by reducing the earning potential of those affected through illness and disability.

Effects of vitamin E and organic selenium on oxidative stability of omega-3 enriched dark chicken meat during cooking.

The influence of vitamin E and selenomethionine (SeMet) on lipid oxidation in frozen-raw and cooked omega-3 enriched dark chicken meat was evaluated. Feed was supplemented with 2 levels of vitamin E (250 and 50 IU/kg of feed) and selenium (0.1 mg of sodium selenite/kg of feed and 0.3 mg of SeMet/kg of feed). An extruded linseed product was used as the alpha-linolenic acid source. Fatty acid (FA) profile, oxysterols, and thiobarbituric reactive acid substances (TBARs) were analyzed in frozen-raw, boiled, pan-fried, and roasted meat. After 6 mo of storage, oxysterols in frozen-raw meat remained stable with either high or low levels of dietary antioxidants. During cooking, high levels of vitamin E reduced oxysterol formation, whereas high levels of SeMet were inconsistent and even increased oxysterols during roasting. TBARs in frozen-raw meat stored for 6 mo were inhibited by high levels of either antioxidant. Conversely, no protective effect during cooking was observed at this time of storage. After 12 mo at -30 degrees C no antioxidant protection was observed.

Two methods for the separation of monounsaturated octadecenoic acid isomers.

The identification and quantification of complex mixtures of cis and trans octadecenoic (18:1) fatty acid isomers presents a major challenge for conventional one-dimensional GC/FID analysis of their methyl esters. We have compared the use of two methods to achieve optimized separations of positional and geometrical octadecenoic fatty acid isomers-comprehensive two-dimensional gas chromatography (GCxGC), and silver ion high performance liquid chromatography interfaced to atmospheric pressure photoionization (APPI) mass spectrometry. Nine isomers of octadecenoic acid methyl ester were well separated on a single silver ion column with a mobile phase of 0.018% acetonitrile and 0.18% isopropanol in hexane. Reproducible retention times were obtained with relative standard deviations of around 1% over 5 injections. The extra selectivity and reproducibility afforded by APPI-MS, together with the wide separation of cis and trans isomers by silver ion chromatography, resulted in a promising method for measurement of octadecenoic acid FAME. The GCxGC separation was performed using various column combinations, and optimal separation was obtained by coupling an ionic liquid column (Supelco SLB-IL100 [1,9-di(3-vinyl-imidazolium) nonane bis(trifluoromethyl) sulfonyl imidate]) in the first dimension with a SGE BPX50 (50% phenyl polysilphenylene-siloxane) in the second dimension. These methods have been applied to the analysis of octadecenoic acid in milk and beef fat.

Early CD44(hi)CD4+ and CD44(hi)CD8+ T cell numbers and the absence of mannose-rich glycoconjugates determine the protective outcome of anti-leishmanial immunity.

Vaccination remains the best hope for control of all forms of leishmaniasis, and the development of a safe and effective vaccine is a critical global public-health priority. Our previous work showed that immunization with non-persistent phosphomannomutase-deficient (DeltaPMM) Leishmania major parasites confers significant protection in susceptible BALB/c mice due to increased T-cell numbers and suppression of IL-10 and IL-13 early during infection. Here, we complemented the DeltaPMM L. major parasites with human PMM2 to determine whether we could further improve the protection. Complemented DeltaPMM parasites have restored glycoconjugate biosynthesis, while retaining avirulence of the parental knockout strain. Immunization with hPMM2 add-back parasites showed similar Th1/Th2 cytokine profiles to that observed in DeltaPMM-vaccinated mice. However, the numbers of the activated CD4+CD44(hi) and CD8+CD44(hi) T cells recruited to the draining lymph nodes early after Leishmania infection were reduced, leading to decreased protection following hPMM2-immunization. Thus, the magnitude of T-cell responses early in the infection and the absence of mannose-rich glycoconjugates determine the protective outcome of anti-leishmanial immunity.

Effect of a lifestyle intervention on change in cardiorespiratory fitness in adults with type 2 diabetes: results from the Look AHEAD Study.

OBJECTIVE: To examine the effect of an intensive lifestyle weight loss intervention (ILI) compared to diabetes support and education (DSE) on changes in fitness and physical activity in the Look AHEAD trial. DESIGN: Randomized clinical trial to compare a lifestyle intervention for weight loss with a DSE condition in individuals with type 2 diabetes. SUBJECTS: Data from 4376 overweight or obese adults with type 2 diabetes (age=58.7+/-6.8 years, body mass index (BMI)=35.8+/-5.8 kg/m(2)) who completed 1 year of the Look AHEAD trial and had available fitness data were analyzed. INTERVENTION: Subjects were randomly assigned to DSE or ILI. DSE received standard care plus three education sessions over the 1-year period. ILI included individual and group contact throughout the year, restriction in energy intake and 175 min per week of prescribed physical activity. MEASUREMENTS: Fitness was assessed using a submaximal graded exercise test. Physical activity was assessed by questionnaire in a subset of 2221 subjects. RESULTS: Change in fitness was statistically greater in ILI vs DSE after adjustment for baseline fitness (20.9 vs 5.7%; P<0.0001). Multivariate analysis showed that change in fitness was greater in overweight vs obese Class II and III (P<0.05). Physical activity increased by 892+/-1694 kcal per week in ILI vs 108+/-1254 kcal per week in DSE (P<0.01). Changes in fitness (r=0.41) and physical activity (r=0.42) were significantly correlated with weight loss (P<0.0001). CONCLUSIONS: The ILI was effective in increasing physical activity and improving cardiorespiratory fitness in overweight and obese individuals with type 2 diabetes. This effect may add to weight loss in improving metabolic control in patients in lifestyle intervention programs.

Sensitivity of population viability to spatial and nonspatial parameters using GRIP.

Metapopulation dynamics are influenced by spatial parameters including the amount and arrangement of suitable habitat, yet these parameters may be uncertain when deciding how to manage species or their habitats. Sensitivity analyses of population viability analysis (PVA) models can help measure relative parameter influences on predictions, identify research priorities for reducing uncertainty, and evaluate management strategies. Few spatial PVAs, however, include sensitivity analyses of both spatial and nonspatial parameters, perhaps because computationally efficient tools for such analyses are lacking or inaccessible. We developed GRIP, a program to facilitate sensitivity analysis of spatial and nonspatial input parameters for PVAs created in RAMAS Metapop, a widely applied software program. GRIP creates random sets of input files by varying parameters specified in the PVA model including vital rates and their correlations among populations, the number and configuration of populations, dispersal rates, dispersal survival, initial population abundances, carrying capacities, and the probability, intensity, and spatial extent of catastrophes, while drawing on specified parameter distributions. We evaluated GRIP's performance as a tool for sensitivity analysis of spatial PVAs and explored the consequences of varying spatial input parameters for predictions of a published PVA model of the sand lizard (Lacerta agilis). We used GRIP output to generate standardized regression coefficients (SRCs) and nonparametric correlation coefficients as indices of the relative sensitivity of predicted conservation status to input parameters. GRIP performed well; with a single analysis we were able to rank the relative influence of input parameters identified as influential by the PVA's original author, S. A. Berglind, who used three separate forms of sensitivity analysis. Our analysis, however, also underscored the value of exploring the relative influence of spatial parameters on PVA predictions; both SRCs and correlation coefficients indicated that the most influential parameters in the sand lizard model were spatial in nature. We provide annotated code so that GRIP may be modified to reflect particular species biology, customized for more complex spatial PVA models, upgraded to incorporate features added in newer versions of RAMAS Metapop, used as a template to develop similar programs, or used as it is for computationally efficient sensitivity analyses in support of conservation planning.

Assessment of silicone gel breast implant biodurability by NMR and EDS techniques.

In a study using explanted gel breast implants and appropriate nonimplanted controls, we examined silicone biodurability after long-term implantation. Using NMR spectroscopy, as well as NMR relaxometry measurements (T(2)), no evidence of hydrolysis or other chemical degradation of the cross-linked silicone matrix was observed in specimens from an early breast implant model (Cronin) explanted after 32 years in vivo or a more recent Silastic II model after 13 years in vivo. In addition, no appreciable differences were seen in T(2) relaxation times comparing explanted breast implants to suitably-matched nonimplanted controls, further underscoring the biostability of the cross-linked silicone shell and gel. Our T(2) data and resultant interpretations differ from a 2004 report by the NMR lab at the University of Münster, highlighting the importance of suitable nonimplanted controls and sample preparation. Energy dispersive spectroscopy (EDS) was also performed, confirming the persistence of a fluorosilicone layer inside the elastomer shells of Silastic II implants.

Wound healing response is a major contributor to the severity of cutaneous leishmaniasis in the ear model of infection.

In the conventional mouse model for cutaneous leishmaniasis involving infection with stationary phase Leishmania major promastigotes at the base of the tail, mice congenic for leishmaniasis resistance loci designated lmr1,2,3 cured their lesions more rapidly and laid down more ordered collagen fibres than the susceptible parental BALB/c mice, while the opposite was the case for the congenic mice carrying the susceptibility loci on the resistant C57BL/6 background. In that model, we showed that wound healing and not T cell responses played a major role in determining the resolution of skin infection. Here, we show a similar disease phenotype in the mouse model that mimics more closely the situation in humans, that is, strictly intradermal infection in the ear pinna with small numbers of metacyclic promastigotes. The data show that at the site of infection the innate and adaptive immune responses act in concert to clear parasites, and induce tissue repair and wound healing. Importantly, the data show that the host responses controlled by the lmr loci, which act locally to control infection in the skin, are distinct from the host responses operating systemically in the draining lymph node.

Paradoxical effects of IL-12 in leishmaniasis in the presence and absence of vaccinating antigen.

Protective immunity against Leishmania major requires parasite-specific CD4+T helper cells, the development of which is promoted by interleukin 12 (IL-12). In this study we investigated the use of IL-12 DNA to enhance the protective immunity induced by prophylactic vaccination with the L. major Parasite Surface Antigen 2 (PSA-2) DNA. A plasmid was constructed in which the two murine IL-12 subunits p35 and p40 were secreted as a biologically active single chain cytokine. The immunomodulatory effects of this IL-12 DNA were examined by codelivery with PSA-2 DNA in susceptible BALB/c and resistant C3H/He mice and subsequent infection with L. major promastigotes. Surprisingly, administration of IL-12 DNA alone had a protective effect, while coadministration of IL-12 with PSA-2 DNA abrogated protection. This effect of IL-12 DNA was dose dependent and affected by the timing of administration in relation to PSA-2 DNA. The effect of IL-12 on protection was associated with a reduced number of INF-gamma-producing T cells early in infection. A further understanding of this paradoxical effect of IL-12 and possibly other cytokines on protective immunity may be important for their use as adjuvants for Leishmania DNA vaccines.

Effects of ionization mode on charge-site-remote and related fragmentation reactions of long-chain quaternary ammonium ions.

Comparison of collisionally activated fragment spectra of long-chain quaternary ammonium ions, formed by liquid-assisted secondary ion mass spectrometry (LSIMS) and electrospray ionization (ESI), shows the latter are dominated by radical cations while the former yield mainly even-electron charge-site-remote (CSR) fragments, similar to the report for different precursors by Cheng et al., J. Am. Soc. Mass Spectrom. 1998, 9, 840. Here, mixed-site fragmentation products (formal loss of a radical directly bonded to the nitrogen plus a radical derived from the long chain) are of comparable importance for both ionization techniques. These observations are difficult to understand if the CSR ions are formed by a concerted rearrangement-elimination reaction, since precollision internal energies of the ESI ions are much lower than those of the ions from LSIMS. Alternatively, if one discards the concerted mechanism for high-energy CA, and assumes that the even-electron fragments are predominantly formed via homolytic bond cleavage, the colder radical cations from ESI survive to the detector while the more energized counterparts from LSIMS preferentially lose a hydrogen atom to yield the CSR ions, as proposed by Wysocki and Ross (Int. J. Mass Spectrom. Ion Processes 1991, 104, 179). The present work also attempts to reconcile discrepancies involving critical energies and known structures for neutral fragments.

Characterization of spirolides a, c, and 13-desmethyl c, new marine toxins isolated from toxic plankton and contaminated shellfish.

Three additional marine toxins, spirolides A (1), C (3), and 13-desmethyl-C (7), were isolated from contaminated scallops and phytoplankton collections obtained from a Nova Scotian aquaculture site, as well as from batch cultures of the dinoflagellate Alexandrium ostenfeldii obtained as a single-cell isolate from these phytoplankton assemblages. The structures of these new spirolide derivatives, characterized by mass spectrometry and NMR, indicate a close relationship with spirolides B (2) and D (4) isolated previously from contaminated shellfish in the same area. All of these compounds display "fast-acting" toxicity in the traditional bioassay used for monitoring shellfish, and this is related to the presence of a cyclic imine function in all these compounds. Those spirolides containing a vicinal dimethyl group in the seven-membered ring are resistant to oxalic acid hydrolysis, whereas those that do not are readily hydrolyzed. These observations suggest that the extra methyl group on the seven-membered imine ring of 3, 4, and 7 appears to block the process of imine hydrolysis perhaps by stereochemical interference.

Therapy of murine cutaneous leishmaniasis by DNA vaccination.

Prophylactic DNA vaccination protects mice against infection with Leishmania major by inducing an exclusive Th1 immune response dominated by the production of IFN-gamma. Here we show that DNA vaccines, initially designed to prevent infection, can also have a significant therapeutic effect. In L. major infected mice, vaccination with DNA encoding the Parasite Surface Antigen/gp46/M2 causes reduction in lesion size and promotes healing in both genetically resistant C3H/He mice and susceptible BALB/c mice. The therapeutic effect is underpinned by a shift in the T cell-derived cytokine environment with an increase in the IFN-gamma producing Th1 type cells. Application of such immunotherapy in conjunction with antiparasite drugs may result in faster or more certain cure of the disease in humans.

Vaccination with recombinant Parasite Surface Antigen 2 from Leishmania major induces a Th1 type of immune response but does not protect against infection.

Vaccination with the native Parasite Surface Antigen 2 of Leishmania major with Corynebacterium parvum as adjuvant protects mice from leishmaniasis through a Th1 mediated response. Here we show that vaccination with a recombinant form of this protein, purified from Escherichia coli and administered in iscoms or with C. parvum as adjuvant, does not induce protective immunity despite the induction of Th1 responses. The results suggest that protective immunity depends on the ability of the vaccinating antigen to induce Th1-like T cells with ability to be recalled by infection. Therefore, the conformation of antigens may play a more major role for the induction of T cell mediated immunity than originally considered.