General practitioner and nurse prescriber experiences of prescribing antibiotics for respiratory tract infections in UK primary care out-of-hours services (the UNITE study)

Background

Interventions are needed to reduce unnecessary antibiotic prescribing for respiratory tract infections (RTIs). Although community antibiotic prescribing appears to be decreasing in the UK, figures for out-of-hours (OOH) prescribing have substantially increased. Understanding the factors influencing prescribing in OOH and any perceived differences between general practitioner (GP) and nurse prescriber (NP) prescribing habits may enable the development of tailored interventions promoting optimal prescribing in this setting.

Objectives

To explore UK GP and NP views on and experiences of prescribing antibiotics for RTIs in primary care OOH services.

Methods

Thirty semi-structured interviews were conducted with GPs and NPs working in primary care OOH services. Inductive thematic analysis was used to analyse data.

Results

The research shows that factors particular to OOH influence antibiotic prescribing, including a lack of patient follow-up, access to patient GP records, consultation time, working contracts and implementation of feedback, audit and supervision. NPs reported perceptions of greater accountability for their prescribing compared with GPs and reported they had longer consultations during which they were able to discuss decisions with patients. Participants agreed that more complex cases should be seen by GPs and highlighted the importance of consistency of decision making, illness explanations to patients as well as a perception that differences in clinical training influence communication with patients and antibiotic prescribing decisions.

Conclusions

Environmental and social factors in OOH services and a mixed healthcare workforce provide unique influences on antibiotic prescribing for RTIs, which would need to be considered in tailoring interventions that promote prudent antibiotic prescribing in OOH services.

Structural and mechanistic insights into a Bacteroides vulgatus retaining N-acetyl-β-galactosaminidase that uses neighbouring group participation

Bacteroides vulgatus is a member of the human microbiota whose abundance is increased in patients with Crohn's disease. We show that a B. vulgatus glycoside hydrolase from the carbohydrate active enzyme family GH123, BvGH123, is an N-acetyl-β-galactosaminidase that acts with retention of stereochemistry, and, through a 3-D structure in complex with Gal-thiazoline, provide evidence in support of a neighbouring group participation mechanism.

Significantly Reduced Catalyst Consumption in Rigid Foams

The use of Mannich base initiated polyether polyols for the production of rigid polyurethane foams has been employed for many years. The use of this class of polyols has primarily been directed toward sprayed polyurethane foam applications. The inherent properties of these polyols include aromatic character, increased compatibility and inherent catalytic capabilities. The use of this family of polyols has not widely spread to other rigid foam applications.

During the transition to HCFC-141b as the primary blowing agent for rigid polyurethane foams, increased catalyst levels were required. This introduced additional cost and handling concerns. This paper presents 20 rigid foam formulations which show how the use of a variety of Mannich polyols can reduce catalyst consumption by more than 40% while maintaining compressive strength, flowability and maintaining or improving the insulation properties of the foam (K-factor) and dimensional stability.

Why women consent to surgery, even when they don't want to: a qualitative study

Although there has been critical analysis of how the informed consent process functions in relation to participation in research and particular ethical 'dilemmas', there has been little examination of consenting to more routine medical procedures. We report a qualitative study of 25 women who consented to surgery. Of these, nine were ambivalent or opposed to having an operation. When faced with a consent form, women's accounts suggest that they rarely do anything other than obey professionals' requests for a signature. An interactionist analysis suggests that women's capacity to act is reduced by the hospital structure of tacit, socially-imposed rules of conduct. Bourdieu's concepts of habitus, capital and symbolic power/violence show how the practical logic that women apply confers a 'sense of place' relative to professionals. Women experience deficits in capital that constrain their ability to exercise choice. This work demonstrates the weakness of the consent process as a safeguard of autonomy.

Trapping and viability of swimming bacteria in an optoelectric trap

Non-contact manipulation methods capable of trapping and transporting swimming bacteria can significantly aid in chemotaxis studies. However, high swimming speed makes the trapping of these organisms an inherently challenging task. We demonstrate that an optoelectric technique, rapid electrokinetic patterning (REP), can effectively trap and manipulate Enterobacter aerogenes bacteria swimming at velocities greater than 20 μm s(-1). REP uses electro-orientation, laser-induced AC electrothermal flow, and particle-electrode interactions for capturing these cells. In contrast to trapping non-swimming bacteria and inert microspheres, we observe that electro-orientation is critical to the trapping of the swimming cells, since unaligned bacteria can swim faster than the radially inward electrothermal flow and escape the trap. By assessing the cell membrane integrity, we study the effect of REP trapping conditions, including optical radiation, laser-induced heating, and the electric field on cell viability. When applied individually, the optical radiation and laser-induced heating have negligible effect on cells. At the standard REP trapping conditions fewer than 2% of cells have a compromised membrane after four minutes. To our knowledge this is the first study detailing the effect of REP trapping on cell viability. The presented results provide a clear guideline on selecting suitable REP parameters for trapping living bacteria.

β+ Gamow-Teller transition strengths from 46Ti and stellar electron-capture rates

The Gamow-Teller strength in the β(+) direction to (46)Sc was extracted via the (46)Ti(t,(3)He + γ) reaction at 115  MeV/u. The γ-ray coincidences served to precisely measure the very weak Gamow-Teller transition to a final state at 991 keV. Although this transition is weak, it is crucial for accurately estimating electron-capture rates in astrophysical scenarios with relatively low stellar densities and temperatures, such as presupernova stellar evolution. Shell-model calculations with different effective interactions in the pf shell-model space do not reproduce the experimental Gamow-Teller strengths, which is likely due to sd-shell admixtures. Calculations in the quasiparticle random phase approximation that are often used in astrophysical simulations also fail to reproduce the experimental Gamow-Teller strength distribution, leading to strongly overestimated electron-capture rates. Because reliable theoretical predictions of Gamow-Teller strengths are important for providing astrophysical electron-capture reaction rates for a broad set of nuclei in the lower pf shell, we conclude that further theoretical improvements are required to match astrophysical needs.

Nuclear structure towards N = 40 60Ca: in-beam γ-ray spectroscopy of 58,60Ti

Excited states in the neutron-rich N = 38, 36 nuclei (60)Ti and (58)Ti were populated in nucleon-removal reactions from (61)V projectiles at 90 MeV/nucleon. The γ-ray transitions from such states in these Ti isotopes were detected with the advanced γ-ray tracking array GRETINA and were corrected event by event for large Doppler shifts (v/c ∼ 0.4) using the γ-ray interaction points deduced from online signal decomposition. The new data indicate that a steep decrease in quadrupole collectivity occurs when moving from neutron-rich N = 36, 38 Fe and Cr toward the Ti and Ca isotones. In fact, (58,60)Ti provide some of the most neutron-rich benchmarks accessible today for calculations attempting to determine the structure of the potentially doubly magic nucleus (60)Ca.

First charge breeding of a rare-isotope beam with the electron-beam ion trap of the ReA post-accelerator at the National Superconducting Cyclotron Laboratory

An electron-beam ion trap (EBIT) charge breeder is being brought into operation at the National Superconducting Cyclotron Laboratory at Michigan State University. The EBIT is part of the ReA post-accelerator for reacceleration of rare isotopes, which are thermalized in a gas "stopping" cell after being produced at high energy by projectile fragmentation. The ReA EBIT has a distinctive design; it is characterized by a high-current electron gun and a two-field superconducting magnet to optimize the capture and charge-breeding efficiency of continuously injected singly charged ion beams. Following a brief overview of the reaccelerator system and the ReA EBIT, this paper presents the latest commissioning results, particularly, charge breeding and reacceleration of the highly charged rare isotopes, (76)Ga(24 +, 25 +).

Cultivation can increase harvesting pressure on overexploited plant populations

Captive breeding and cultivation of overharvested species is frequently proposed as a conservation strategy, yet there is little evidence under what conditions, if at all, the strategy is effective. We created a bioeconomic model to investigate the socioeconomic conditions favoring cultivation over wild harvesting and likely impacts on the wild population. We parameterize the model with the case study of illegal xaté palm (Chamaedorea ernesti-augusti) harvesting in Belize and Guatemala. We examine how changes in law enforcement, a price premium for cultivated leaf, land ownership, and alternative income might affect decisions to cultivate and the impact of cultivation on wild populations. We show that those switching to cultivation are largely not wild harvesters because of barriers such as land ownership. We also find that if harvesters do switch to cultivation, they may have a negative effect on the wild population through harvesting of material to set up plantations. We found increasing alternative income reduces harvesting pressure and suggests the provision of alternative livelihoods would more directly reduce pressure on the wild population. Although schemes to encourage cultivation seem an appealing conservation intervention, we urge caution in assuming that people will readily adopt cultivation of wild harvested species or that this would necessarily reduce impacts on wild populations.

Direct observation of long-lived isomers in 212Bi

Long-lived isomers in (212)Bi have been studied following (238)U projectile fragmentation at 670 MeV per nucleon. The fragmentation products were injected as highly charged ions into a storage ring, giving access to masses and half-lives. While the excitation energy of the first isomer of (212)Bi was confirmed, the second isomer was observed at 1478(30) keV, in contrast to the previously accepted value of >1910 keV. It was also found to have an extended Lorentz-corrected in-ring half-life >30 min, compared to 7.0(3) min for the neutral atom. Both the energy and half-life differences can be understood as being due a substantial, though previously unrecognized, internal decay branch for neutral atoms. Earlier shell-model calculations are now found to give good agreement with the isomer excitation energy. Furthermore, these and new calculations predict the existence of states at slightly higher energy that could facilitate isomer deexcitation studies.

The Effects of the Chemical and Radiolytic Degradation of Asphalt on Plutonium Solubility

The influence of alkaline degradation or radiolytic degradation of asphalt on plutonium solubility has been investigated. Asphalt has been contacted with water, sodium hydroxide solution or concrete leachate at 80°C for periods of up to approximately 2 years. Sodium nitrate was also present in some of the experiments. Plutonium solubilities were measured at pH 12 in the leachates and found to be less than 10-8 mol dm-3 for most degradations. Relatively low levels of Total Organic Carbon were measured in the leachates. Alpha radiolysis of asphalt in the presence of concrete and water has also been studied. Samples of asphalt were encapsulated in concrete after coating with the 238PuO2, crushed and leached at room temperature. The solubility of plutonium was measured in samples of the leachates after approximately 90 days and 180 days had elapsed. The results showed that the solubility of plutonium in the α-radiolysis leachates remained low and was in the range 2 × 10-11 to 8 × 10-9 mol dm-3. A consideration of these results, and data published elsewhere, suggests that chemical and radiolytic attack on asphalt or bitumen under anaerobic, alkaline conditions typical of a deep cementitious repository is unlikely to generate complexants for plutonium which are effective at high pH. Any enhancement of plutonium solubility is likely to be less significant than that arising from the degradation of some other organic materials.

High-precision measurement of the 19Ne half-life and implications for right-handed weak currents

We report a precise determination of the (19)Ne half-life to be T(1/2)=17.262±0.007 s. This result disagrees with the most recent precision measurements and is important for placing bounds on predicted right-handed interactions that are absent in the current standard model. We are able to identify and disentangle two competing systematic effects that influence the accuracy of such measurements. Our findings prompt a reassessment of results from previous high-precision lifetime measurements that used similar equipment and methods.

Complete Barrett's excision by stepwise endoscopic resection in short-segment disease: long term outcomes and predictors of stricture

BACKGROUND AND STUDY AIMS

Complete Barrett's excision (CBE) of short-segment Barrett's high grade dysplasia (HGD) and early esophageal adenocarcinoma by stepwise endoscopic resection is a precise staging tool, detects covert synchronous disease, and may produce a sustained treatment response. Esophageal stricture is the most commonly reported complication of CBE although risk factors have not yet been clearly defined.

PATIENTS AND METHODS

Data were recorded prospectively on patients with limited co-morbidity and age ≤ 80 years undergoing CBE for histologically proven HGD or esophageal adenocarcinoma within ≤ C3M5 segments. Endoscopic resection was performed by standardized protocol every 6 - 8 weeks until CBE was achieved. Esophageal dilation was performed when patients reported dysphagia. Dysphagia scores were recorded at scheduled endoscopic surveillance or by telephone interview.

RESULTS

By intention-to-treat analysis, complete eradication of neoplasia and intestinal metaplasia was achieved in 95 % and 82 %, respectively, in 77 patients undergoing a median of 2 resection sessions (interquartile range [IQR] 1 - 3). Esophageal dilation was required in 33 % (median 3 dilations, IQR 1 - 3.5) at median follow-up of 20 months (IQR 6 - 40). Independent risk factors for dilation requirement were the number of mucosal resections at the index procedure (odds ratio [OR] 1.3 per resection, 95 % confidence interval [CI] 1.0 - 1.9; P = 0.043) and maximal extent of the Barrett's segment (OR 2.2 per cm, 95 %CI 1.2 - 3.9; P = 0.009).

CONCLUSIONS

Although CBE is highly effective in the treatment of Barrett's HGD and esophageal adenocarcinoma, the risk of post-CBE dysphagia increases with the maximal extent of the Barrett's segment and the number of mucosal resections at the index procedure. These data could be used to inform treatment decisions and identify those patients who may benefit from prophylactic therapies such as dilation.

Serpina3n attenuates granzyme B-mediated decorin cleavage and rupture in a murine model of aortic aneurysm

Granzyme B (GZMB) is a proapoptotic serine protease that is released by cytotoxic lymphocytes. However, GZMB can also be produced by other cell types and is capable of cleaving extracellular matrix (ECM) proteins. GZMB contributes to abdominal aortic aneurysm (AAA) through an extracellular, perforin-independent mechanism involving ECM cleavage. The murine serine protease inhibitor, Serpina3n (SA3N), is an extracellular inhibitor of GZMB. In the present study, administration of SA3N was assessed using a mouse Angiotensin II-induced AAA model. Mice were injected with SA3N (0–120 μg/kg) before pump implantation. A significant dose-dependent reduction in the frequency of aortic rupture and death was observed in mice that received SA3N treatment compared with controls. Reduced degradation of the proteoglycan decorin was observed while collagen density was increased in the aortas of mice receiving SA3N treatment compared with controls. In vitro studies confirmed that decorin, which regulates collagen spacing and fibrillogenesis, is cleaved by GZMB and that its cleavage can be prevented by SA3N. In conclusion, SA3N inhibits GZMB-mediated decorin degradation leading to enhanced collagen remodelling and reinforcement of the adventitia, thereby reducing the overall rate of rupture and death in a mouse model of AAA.

Factors that predict bleeding following endoscopic mucosal resection of large colonic lesions

BACKGROUND AND STUDY AIMS

Endoscopic mucosal resection (EMR) for large colonic laterally spreading tumors (LSTs) is a safe, efficacious, and cost-effective treatment. The most common serious complication is delayed bleeding, which reduces these advantages, but consensus guidelines for large-polyp EMR do not exist.

PATIENTS AND METHODS

Data from two large prospective intention-to-treat studies of EMR for colonic LSTs 20 mm or greater in size were analyzed. Data collection was comprehensive, and included patient and lesion characteristics. EMR technique and cessation of anticoagulant and antiplatelet therapy was standardized. Clinically significant delayed bleeding was defined as that requiring hospital admission.

RESULTS

EMR was performed on 302 lesions in 288 patients. There was clinically significant delayed bleeding in 21 cases (7 %). Ten underwent colonoscopy. One required angiography. One required surgery after perforation following hemostatic clip placement. There were no deaths. Risk factors for bleeding on multivariate analysis were right colon location [adjusted odds ratio (OR) 4.4, P = 0.01], use of aspirin (OR 6.3, P = 0.005), and age (OR per decade of age 1.70). All bleeds occurred before aspirin was restarted. Patient characteristics, including ASA grade and co-morbidity type, were not predictive. Despite requiring more complex EMR, larger lesion size ( P = 0.2), multiple excisions rather than en bloc resection ( P = 0.1), polyp morphology ( P = 0.2), and previous attempts ( P = 0.5), were not associated with increased risk.

CONCLUSIONS

Proximal lesion location is a highly significant risk for clinically significant delayed bleeding following colonic EMR, and this knowledge could form the basis of a targeted therapeutic trial. Recent aspirin use also increases bleeding risk--specific consensus guidelines in this area are required for colonic EMR.

The Solubility of Actinides in the Near-Field

The solubility of some of the radiologically important actinide elements have been determined in a water whose chemistry was representative of that believed to exist in potential repositories in the U.K. The solubilities of the actinides have been determined as a function of the pH of the water. The results of these experiments have been compared with the results of predictions made using the PHREEQE geochemical modelling code in order to test and validate the data base used in the model. In the light of these comparisons, suggestions are made for alternative values for the thermodynamic data and for further studies.

The Identification and Degradation of Isosaccharinic Acid, a Cellulose Degradation Product

Nirex is seeking to develop a deep underground repository for the disposal of solid intermediate-level and low-level radioactive wastes (ILW and LLW) in the UK. One possible influence on the behaviour of radionuclides is the formation of water-soluble complexants by the degradation of the solid organic polymers that will be present in the wastes. The degradation products of cellulose have been shown to increase the solubility of plutonium and other radionuclides and to reduce sorption onto near-field and far-field materials. Degradation of cellulose under anaerobic alkaline conditions produces a range of organic acids. In this paper 2-C-(hydroxymethyl)-3-deoxy-D-pentonic acid (isosaccharinic acid, ISA) is identified by High Performance Liquid Chromatography as a significant component of cellulose leachates. A combination of fractionation of cellulose leachates and plutonium solubility determinations shows that ISA is responsible for the majority of the enhancement of plutonium solubility observed in such leachates. Further degradation of ISA by chemical or microbial action may lessen the effect of degraded cellulose leachates. Experimental studies on the chemical degradation of this compound under alkaline conditions suggest that the presence of oxygen is required. Microbial degradation studies show that the plutonium solubility in solutions of ISA is reduced by their exposure to microbial action.

Sorption of Plutonium and Americium on Repository, Backfill and Geological Materials Relevant to The JNFL Low-Level Radioactive Waste Repository at Rokkasho-Mura

An integrated programme of batch sorption experiments and mathematical modelling has been carried out to study the sorption of plutonium and americium on a series of repository, backfill and geological materials relevant to the JNFL low-level radioactive waste repository at Rokkasho-Mura.

The sorption of plutonium and americium on samples of concrete, mortar, sand/bentonite, tuff, sandstone and cover soil has been investigated. In addition, specimens of bitumen, cation and anion exchange resins, and polyester were chemically degraded. The resulting degradation product solutions, alongside solutions of humic and iso-saccharinic acids were used to study the effects on plutonium sorption onto concrete, sand/bentonite and sandstone.

The sorption behaviour of plutonium and americium has been modelled using the geochemical speciation program HARPHRQ in conjunction with the HATCHES database.

High-precision half-life measurement for the superallowed β+ emitter ²⁶Al(m)

A high-precision half-life measurement for the superallowed β+ emitter 26Al(m) was performed at the TRIUMF-ISAC radioactive ion beam facility yielding T 1/2 6346.54 ± 0.46(stat) ± 0.60 (syst) ms, consistent with, but 2.5 times more precise than, the previous world average. The 26Al(m) half-life and ft value, 3037.53(61) s, are now the most precisely determined for any superallowed β decay. Combined with recent theoretical corrections for isospin-symmetry-breaking and radiative effects, the corrected Ft value for (26)Al(m), 3073.0(12) s, sets a new benchmark for the high-precision superallowed Fermi β-decay studies used to test the conserved vector current hypothesis and determine the V(ud) element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix.

Granzymes in age-related cardiovascular and pulmonary diseases

Chronic inflammation is a hallmark of age-related cardiovascular and pulmonary diseases. Granzymes are a family of serine proteases that have been traditionally viewed as initiators of immune-mediated cell death. However, recent findings suggest that the pathophysiological role of granzymes is complex. Emerging functions for granzymes in extracellular matrix degradation, autoimmunity, and inflammation suggests a multifactorial mechanism by which these enzymes are capable of mediating tissue damage. Recent discoveries showing that granzymes can be produced and secreted by nonimmune cells during disease provide an additional layer of intricacy. This review examines the emerging biochemical and clinical evidence pertaining to intracellular and/or extracellular granzymes in the pathogenesis of aging and cardiopulmonary diseases.

Spatiotemporal expression of α1, α3 and β1 integrin subunits is altered in rat myometrium during pregnancy and labour

Integrins are transmembrane extracellular matrix (ECM) receptors composed of α- and β-subunits. Integrins can cluster to form focal adhesions and, because there is significant ECM remodelling and focal adhesion turnover in the rat myometrium during late pregnancy, we hypothesised that the expression of α1, α3 and β1 integrin subunits in the rat myometrium would be altered at this time to accommodate these processes. Expression of α1 and β1 integrin subunit mRNA was significantly increased on Days 6–23 of pregnancy compared with non-pregnant (NP) and postpartum (PP) time points (P < 0.05). In contrast, α3 integrin subunit mRNA expression was significantly increased on Days 14, 21 and 22 compared with NP, Day 10, 1 day PP and 4 days PP (P < 0.05). A relative gene expression study revealed that, of the integrins studied, the expression of β1 integrin mRNA was highest in pregnant rat myometrium. The α1, α3 and β1 integrin subunit proteins became immunolocalised to myocyte membranes in situ by late pregnancy and labour in both myometrial muscle layers. Increased α1, α3 and β1 integrin gene expression during gestation and the specific detection of these subunits in myocyte membranes during late pregnancy and labour may contribute to the cell–ECM interactions required for the development of a mechanical syncytium.

The suction pseudopolyp technique: a novel method for the removal of small flat nonpolypoid lesions of the colon and rectum

BACKGROUND AND STUDY AIMS

Small flat nonpolypoid lesions of the colorectum can be technically difficult to target and completely remove; techniques such as hot biopsy forceps electrocauterization are associated with serositis, delayed bleeding, and perforation. This study aimed to describe a novel technique for the removal of such lesions and demonstrate its safety and efficacy.

PATIENTS AND METHODS

Patients aged 18 - 80 years with flat nonpolypoid lesions (Paris-Japanese classification 0-IIa and 0-IIb, measuring less than 10 mm) identified at colonoscopy were included in this prospective study. The lesions were removed by the suction pseudopolyp technique (SPT): the lesion is aspirated into the suction channel of the colonoscope and continuous suction applied for 5 seconds whilst the colonoscope is gently retracted. On release of the suction, the resulting pseudopolyp containing the lesion and a margin of normal tissue is easily ensnared and resected. The primary outcomes were endoscopic completeness of polyp resection and complication rate.

RESULTS

Over a 12-month period, 1231 polyps were removed during 2656 colonoscopies; 126 polyps (in 101 patients) met inclusion criteria. Complete endoscopic resection was achieved in 100 % of the polyps, without immediate or delayed complication. Of the resected lesions, 57 % had malignant potential (adenomas 47 % and sessile serrated lesions 10 %); a higher proportion of lesions removed from the right colon had malignant potential compared with those from the left colon (75 % vs. 41 %, P = 0.0066).

CONCLUSIONS

Diminutive flat lesions of the colorectum are predominantly adenomas and sessile serrated lesions. SPT is a safe, effective, and reproducible therapy for removal of these lesions.

Technetium behaviour in Boom Clay – a laboratory and field study

This paper describes a study of technetium solubility and migration under chemical conditions representative of those prevailing in a Boom Clay environment. Laboratory andin situmeasurements yielded similar aqueous concentrations of technetium, of about 1×10−8mol dm−3, close to the concentrations measured for hydrated technetium(IV) oxide TcO2·1.6H2O in the solubility studies. From fitting the curves of the Tc concentrations as function of time, distribution coefficient (Kd) values were estimated to lie between 0.8 cm3g−1and 1.8 cm3g−1. Exposure of the system at 80 °C and to γ-radiation dose rates of several hundred Gy h−1resulted in only minor differences in behaviour.

A prospective randomized trial of cannulation technique in ERCP: effects on technical success and post-ERCP pancreatitis

BACKGROUND AND STUDY AIMS

Inadvertent injection of contrast agent into the pancreatic duct is believed to be an important contributor to pancreatitis occurring after endoscopic retrograde cholangiopancreatography (post-ERCP pancreatitis, PEP). Our aim was to examine whether primary deep biliary cannulation with a guide wire is associated with a lower rate of PEP than conventional contrast-assisted cannulation.

PATIENTS AND METHODS

From August 2003 to April 2006 all patients with an intact papilla who were referred for ERCP were eligible. Patients with pancreatic or ampullary cancer were excluded. Patients were randomized to undergo sphincterotomy biliary cannulation using either contrast injection or a guide wire. The ERCP fellow attempted initially for 5 minutes. If unsuccessful, the consultant attempted for 5 minutes using the same technique, followed by crossover to the other technique in the same sequence and then needle-knife sphincterotomy where appropriate. Patients were assessed clinically after the procedure, then followed up with telephone interviews after 24 hours and 30 days, and serum amylase and lipase tests after 24 hours.

RESULTS

Out of 1654 patients undergoing ERCP, 413 were included in the study. PEP occurred in 29/413 (7.0 %): 16 in the guide-wire arm, 13 in the contrast arm ( P = 0.48). The overall cannulation success rate was 97.3 %. Cannulation was successful without crossover in 323/413 patients (78.2 %): 167/202 (81.4 %) in the guide-wire arm and 156/211 (73.9 %) in the contrast arm ( P = 0.03). Multivariate analysis demonstrated female sex (OR = 2.7, P = 0.04), suspected sphincter of Oddi dysfunction (OR = 5.5, P = 0.01), and complete filling of the pancreatic duct with contrast agent (OR = 3.5, P = 0.02) to be independently associated with PEP. The risk of PEP increased incrementally with each attempt at the papilla (OR 1.4 per attempt, P = 0.04) to greater than 10 % after four or more attempts.

CONCLUSIONS

The guide-wire technique improves the primary success rate for biliary cannulation during ERCP but does not reduce the incidence of PEP compared to the conventional contrast technique. The incidence of PEP increases incrementally with each attempt at the papilla.

Restriction of placental function alters heart development in the sheep fetus

Placental insufficiency, resulting in restriction of fetal substrate supply, is a major cause of intrauterine growth restriction (IUGR) and increased neonatal morbidity. Fetal adaptations to placental restriction maintain the growth of key organs, including the heart, but the impact of these adaptations on individual cardiomyocytes is unknown. Placental and hence fetal growth restriction was induced in fetal sheep by removing the majority of caruncles in the ewe before mating (placental restriction, PR). Vascular surgery was performed on 13 control and 11 PR fetuses at 110-125 days of gestation (term: 150 +/- 3 days). PR fetuses with a mean gestational Po(2) < 17 mmHg were defined as hypoxic. At postmortem (<135 or >135 days), fetal hearts were collected, and cardiomyocytes were isolated and fixed. Proliferating cardiomyocytes were counted by immunohistochemistry of Ki67 protein. Cardiomyocytes were stained with methylene blue to visualize the nuclei, and the proportion of mononucleated cells and length and width of cardiomyocytes were measured. PR resulted in chronic fetal hypoxia, IUGR, and elevated plasma cortisol concentrations. Although there was no difference in relative heart weights between control and PR fetuses, there was an increase in the proportion of mononucleated cardiomyocytes in PR fetuses. Whereas mononucleated and binucleated cardiomyocytes were smaller, the relative size of cardiomyocytes when expressed relative to heart weight was larger in PR compared with control fetuses. The increase in the relative proportion of mononucleated cardiomyocytes and the relative sparing of the growth of individual cardiomyocytes in the growth-restricted fetus are adaptations that may have long-term consequences for heart development in postnatal life.

Small rat islets are superior to large islets in in vitro function and in transplantation outcomes

Barriers to the use of islet transplantation as a practical treatment for diabetes include the limited number of available donor pancreata. This project was designed to determine whether the size of the islet could influence the success rate of islet transplantations in rats. Islets from adult rats were divided into two groups containing small (diameter <125 microm) or large (diameter >150 microm) islets. An average pancreas yielded three times more small islets than large. Smaller islets were approximately 20% more viable, with large islets containing a scattered pattern of necrotic and apoptotic cells or central core cell death. Small islets in culture consumed twice as much oxygen as large islets when normalized for the same islet equivalents. In static incubation, small islets released three times more insulin under basal conditions than did large islets. During exposure to high glucose conditions, the small islets released four times more insulin than the same islet equivalencies of large islets, and five times more insulin was released by the small islets in response to glucose and depolarization with K+. Most importantly, the small islets were far superior to large islets when transplanted into diabetic animals. When marginal islet equivalencies were used for renal subcapsular transplantation, large islets failed to produce euglycemia in any recipient rats, whereas small islets were successful 80% of the time. The results indicate that small islets are superior to large islets in in vitro testing and for transplantation into the kidney capsule of diabetic rats.

58Ni: an unpaired band crossing at new heights of angular momentum for rotating nuclei

High-spin states in 58Ni have been investigated by means of the fusion-evaporation reaction 28Si(32S, 2p)58Ni at 130 MeV beam energy. Discrete-energy levels are observed in 58Ni at record-breaking 42 MeV excitation energy and angular momenta in excess of 30h. The states form regular rotational bands with unprecedented high rotational frequencies. A comparison with configuration dependent cranked Nilsson-Strutinsky calculations reveals an exceptional two-band crossing scenario, the interaction strength of which is strongly shape dependent.

Argon plasma coagulation in the management of symptomatic gastrointestinal vascular lesions: experience in 100 consecutive patients with long-term follow-up

BACKGROUND

The long-term efficacy of argon plasma coagulation (APC) in the management of gastrointestinal vascular lesions has not been evaluated in a large and well-defined series. The impact of APC on transfusion requirements and hemoglobin, and technical parameters including complications and number of treatment sessions, is assessed in this series.

METHODS

Patients who underwent APC for bleeding gastrointestinal vascular lesions were identified via interrogation of an established endoscopic database, excluding patients with radiation proctitis, tumors, residual polypectomy tissue and acute ulcer bleeding. Follow-up data were collected via interview with patients and referring doctors, review of medical records, and follow-up blood tests.

RESULTS

One hundred patients were enrolled, males = 46, median age = 74 yr (range: 19-99 yr). Median follow-up time was 16 months (range: 4-47 months). Lesions treated were arteriovenous malformations (n = 74) and gastric antral vascular ectasia (n = 26). Fifty-three patients required transfusion. In this group, median hemoglobin improved from 66 g/L (range: 35-114) to 111 g/L (range: 55-155, p < 0.001). Median transfusion velocity fell from 2 units/month (range: 0.1-6) to 0 units/month (range: 0-4, p < 0.001). Transfusion requirement was abolished in 77%. In non-transfusion-requiring patients, median hemoglobin improved from 105 g/L (range: 58-143) to 123 g/L (range: 79-158, p < 0.001). No complications occurred.

CONCLUSIONS

APC is effective and safe in the management of gastrointestinal vascular lesions.

Expression of α5 Integrin (Itga5) Is Elevated in the Rat Myometrium During Late Pregnancy and Labor: Implications for Development of a Mechanical Syncytium1

The underlying mechanisms controlling uterine contractions during labor are still poorly understood. Integrins are heterodimeric, transmembrane receptors composed of alpha and beta subunits that can be found in focal adhesions. Because these structures play an important role in the regulation of smooth muscle contractility and cell adhesion, we hypothesized that alpha5 integrin mRNA (Itga5) and protein (ITGA5) expression would be induced in the rat myometrium during late pregnancy and labor. Itga5 mRNA expression was significantly increased (P < 0.05) from Day 17 to labor, noticeably decreasing 1 day postpartum (PP). Immunoblot analysis illustrated a continual increase in ITGA5 levels during pregnancy, labor, and PP, with levels reaching significance at labor (P < 0.05). Analysis of ITGA5 expression by immunocytochemistry demonstrated that it is primarily localized to myometrial cell membranes in the longitudinal muscle layer of the myometrium from before pregnancy to Day 6, and in both the longitudinal and circular muscle layers from Day 15 to PP. Treatment of late-pregnant rats with progesterone blocked labor and resulted in sustained expression of Itga5 mRNA expression to Day 24. In addition, immunocytochemistry experiments showed ITGA5 was detectable at higher levels in cell membranes of both myometrial layers in progesterone-treated animals on Days 23 and 24, compared with vehicle controls. We propose that ITGA5, with its sole known partner, ITGB1, may be important in promoting cellular cohesion during late pregnancy. This process may aid the development of a mechanical syncytium for efficient force transduction during the sustained, coordinated, and powerful contractions of labor.

Increased myogenic tone in 7-month-old adult male but not female offspring from rat dams exposed to hypoxia during pregnancy

Intrauterine growth restriction (IUGR) increases the risk of cardiovascular disease later in life. Vascular dysfunction occurs in adult offspring from animal models of IUGR including maternal undernutrition, but the influence of reduced fetal oxygen supply on adult vascular function is unclear. Myogenic responses, essential for vascular tone regulation, have not been evaluated in these offspring. We hypothesized that 7-mo-old offspring from hypoxic (12% O(2); H) or nutrient-restricted (40% of control; NR) rat dams would show greater myogenic responses than their 4-mo-old littermates or control (C) offspring through impaired modulation by vasodilators. Growth restriction occurred in male H (P < 0.01), male NR (P < 0.01), and female NR (P < 0.02), but not female H, offspring. Myogenic responses in mesenteric arteries from males but not females were increased at 7 mo in H (P < 0.01) and NR (P < 0.05) vs. C offspring. There was less modulation of myogenic responses after inhibition of nitric oxide synthase (P < 0.05), prostaglandin H synthase (P < 0.005), or both enzymes (P < 0.001) in arteries from 7-mo male H vs. C offspring. Thus reduced vasodilator modulation may explain elevated myogenic responses in 7-mo male H offspring. In contrast, there was increased modulation of myogenic responses in arteries from 7-mo female H vs. C or NR offspring after inhibition of both enzymes (P < 0.05). Thus increased vasodilator modulation may maintain myogenic responses in female H offspring at control levels. In summary, vascular responses in adult offspring from adverse intrauterine environments are impaired in a gender-specific, age-dependent, and maternal insult-dependent manner, with males more profoundly affected.

Small heat shock protein 27 (Hsp27) expression is highly induced in rat myometrium during late pregnancy and labour

The underlying mechanisms that regulate uterine contractions during labour are still poorly understood. A candidate regulatory protein is heat shock protein 27 (Hsp27). It belongs to the small heat shock protein family and can regulate actin cytoskeleton dynamics, act as a chaperone, and may regulate contractile protein activation. As a result, we hypothesized that Hsp27 expression would be highly induced during late pregnancy and labour. Hsp27 mRNA expression was significantly elevated (P <0.05) on days 17 to 22 of gestation. In addition, immunoblot analysis demonstrated that detection of total Hsp27 increased (P <0.05) between day 21 and 1 day post-partum (PP) inclusive. Since phosphorylation of Hsp27 has been reported to be a prerequisite for smooth muscle contraction, we examined the temporal and spatial expression of Ser-15 phosphorylated Hsp27. Immunoblot analysis showed that the detection of Ser-15 phosphorylated Hsp27 significantly increased (P <0.05) between days 19 and 23 (active labour) inclusive, in parallel with detection of total Hsp27. Immunocytochemical analysis of Ser-15 phosphorylated Hsp27 expression in situ demonstrated that phosphorylated Hsp27 in circular muscle became detectable in peri-nuclear and membrane regions on days 19 to 22, but was primarily restricted to the cytoplasm on days 23 to PP. In contrast, phosphorylated Hsp27 in longitudinal muscle was primarily detected in myocyte membranes on days 15 to 22, and then also became detectable in the cytoplasm of myocytes on days 23 and PP. Our results demonstrate that Hsp27 expression is highly upregulated during late pregnancy and labour and suggest that Hsp27 is a potential candidate contraction-associated protein.

Investigation of quantitative secondary electron imaging of semiconducting polymer materials using environmental scanning electron microscopy

The development of environmental scanning electron microscopy has opened the way for the examination of a wide variety of new sample types that were previously inaccessible to conventional scanning electron microscope techniques. With the advent of such a new methodology comes also the potential for new contrast mechanisms. We investigated the use of environmental scanning electron microscopy on semiconducting organic polymer materials. We observed contrast from these materials in secondary electron images, this contrast being attributed to differences in electron yield due to the polymer's electronic structure. Further study of these materials, and specifically the influence of film thickness on signal, has indicated a significant effect as the secondary electrons move through the sample. Systematic studies such as these are needed for a full understanding of the relationship between electronic properties and signal and, hence, the ability to probe structure-property relationships in greater depth.

Application of disposable plastic microfluidic device arrays with customized chemistries to multiplexed biochemical assays

Plastic microfluidic array platforms and synergistic multiplexed assay chemistries are under development for a variety of applications, including assays of gene expression, proteomics, genotyping, DNA sequencing and fragment analysis, sample preparation and high-throughput pharmaceutical discovery. The low production costs of plastic substrates makes possible economical single-use device arrays, eliminating cleaning and sample-to-sample carryover contamination. Hundreds of microchannels and reservoirs are readily included on a single microtitre-plate-size substrate, enabling the manufacture of highly parallel fluidic array systems to increase throughput and speed.

Glycosynthases: Mutant Glycosidases for Glycoside Synthesis

Glycosynthases are engineered mutant glycosidases that catalyse the formation of a glycosidic bond from a glycosyl donor and an acceptor alcohol. They are constructed by mutation of the enzymic nucleophile of a retaining glycosidase to a small non-nucleophilic residue. To date, five glycosynthases have been reported capable of synthesizing a range of β-glycosidic linkages. Methods to integrate protecting groups into glycosynthase-mediated glycosylations have been developed that broaden their applicability and enable finer control over product formation. Mutagenesis studies have improved the catalytic power of the original Abg glycosynthase, and a general methodology has been developed that allows the rapid screening of libraries of mutant glycosynthases for catalysts with improved activity. A method for determining aglycon substrate specificity has been developed to define the limits of substrate variation tolerated by a parent glycosidase and thence the derived glycosynthase. Together, these developments portend a bright future for the discovery of new glycosynthases and their widespread application as catalysts to assist in the rapid and efficient assembly of complex glycoconjugates.