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Summary: We conducted the first comparison of dual-energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) outcomes in adolescent girls with anorexia nervosa. We observed deficits in bone density by both tools. pQCT assessments were associated with many of the same clinical parameters as have been previously established for DXA. Introduction: Adolescents with anorexia nervosa (AN) commonly exhibit bone loss, but effects on bone geometry are less clear. We compared measures obtained by DXA and pQCT in girls with AN. Methods: Seventy females (age 15.5 ± 1.9 years ) with AN and 132 normal-weighted controls underwent tibial measures by pQCT including trabecular volumetric bone mineral density (vBMD) at the 3 % site, cortical vBMD and dimensions at the 38 % site, and muscle cross-sectional area (CSA) at the 66 % site. Participants with AN also underwent standard DXA measures. Independent t tests compared the pQCT results, while Pearson coefficient assessed correlations among DXA and pQCT measures. Results: Trabecular vBMD Z-scores were lower in AN compared to controls (AN −0.31 ± 1.42 vs +0.11 ± 1.01, p = 0.01) and cortical vBMD Z-scores were higher (AN +0.18 ± 0.92 vs −0.50 ± 0.88, p < 0.001). Trabecular vBMD and cortical CSA Z-scores positively correlated with DXA BMD Z-scores ( r range 0.57-0.82, p < 0.001). Markers of nutritional status positively correlated with Z-scores for trabecular vBMD, cortical CSA, section modulus, and muscle CSA ( p < 0.04 for all). Conclusions: This study is the first to compare DXA and pQCT measurements in adolescent girls with AN. We observed deficits in BMD by both DXA and pQCT. pQCT assessments correlated well with DXA bone and body composition measures and were associated with many of the same clinical parameters and disease severity markers as have been previously established for DXA. The differences in cortical vBMD merit further study. [ABSTRACT FROM AUTHOR]

Individual exposure to stressors can induce changes in physiological stress responses through modulation of the hypothalamic-pituitary-interrenal (HPI) axis. Despite theoretical predictions, little is known about how individuals will respond to unpredictable short-lived stressors, such as thermal events. We examine the primary neuroendocrine response of coral reef fish populations from the Îles Eparses rarely exposed to anthropogenic stress, but that experienced different thermal histories. Skunk anemonefish, Amphiprion akallopisos, showed different cortisol responses to a generic stressor between islands, but not along a latitudinal gradient. Those populations previously exposed to higher maximum temperatures showed greater responses of their HPI axis. Archive data reveal thermal stressor events occur every 1.92-6 yr, suggesting that modifications to the HPI axis could be adaptive. Our results highlight the potential for adaptation of the HPI axis in coral reef fish in response to a climate-induced thermal stressor. [ABSTRACT FROM AUTHOR]

The impact of commencing or changing antiplatelet therapy on von Willebrand factor antigen (VWF:Ag) and von Willebrand factor propeptide (VWF:Ag II) levels has not been comprehensively assessed following TIA or ischaemic stroke. In this pilot, longitudinal, observational analytical study, VWF:Ag and VWF:Ag II levels were simultaneously quantified in platelet poor plasma by ELISA in patients within 4 weeks of TIA or ischaemic stroke (baseline), and then 14 days (14d) and >90 days (90d) after altering antiplatelet therapy. Ninety-one patients were recruited. Eighteen were initially assessed on no antiplatelet therapy, and then after 14d ( N = 17) and 90d ( N = 8) on aspirin monotherapy; 21 patients were assessed on aspirin and after 14d and 90d on clopidogrel; 52 were assessed on aspirin monotherapy, and after 14d and 90d on aspirin and dipyridamole combination therapy. VWF:Ag, VWF:Ag II levels and VWF:Ag/VWF:Ag II ratio were unchanged at 14d and 90d in the overall study population ( p ≥ 0.1). VWF:Ag and VWF:Ag II levels remained stable at 14d and 90d after commencing aspirin ( p ≥ 0.054), and after changing from aspirin to clopidogrel ( p ≥ 0.2). Following the addition of dipyridamole MR to aspirin, there was a significant reduction in VWF:Ag levels at 14d ( p = 0.03) and 90d ( p = 0.005), but not in VWF:Ag II levels ( p ≥ 0.3). The addition of dipyridamole to aspirin led to a persistent reduction in VWF:Ag but not in VWF:Ag II levels, suggesting that dipyridamole may inhibit release of platelet-derived VWF:Ag following TIA or ischaemic stroke. [ABSTRACT FROM AUTHOR]

Climate change presents a new challenge for the management of invasive exotic species that threaten both biodiversity and agricultural productivity. The invasion of exotic perennial grasses throughout the globe is particularly problematic given their impacts on a broad range of native plant communities and livelihoods. As the climate continues to change, pre-emptive long-term management strategies for exotic grasses will become increasingly important. Using species distribution modelling we investigated potential changes to the location of climatically suitable habitat for some exotic perennial grass species currently in Australia, under a range of future climate scenarios for the decade centred around 2050. We focus on eleven species shortlisted or declared as the Weeds of National Significance or Alert List species in Australia, which have also become successful invaders in other parts of the world. Our results indicate that the extent of climatically suitable habitat available for all of the exotic grasses modelled is projected to decrease under climate scenarios for 2050. This reduction is most severe for the three species of Needle Grass (genus Nassella) that currently have infestations in the south-east of the continent. Combined with information on other aspects of establishment risk (e.g. demographic rates, human-use, propagule pressure), predictions of reduced climatic suitability provide justification for re-assessing which weeds are prioritised for intensive management as the climate changes. [ABSTRACT FROM AUTHOR]

The impact of changing antiplatelet therapy on thrombin generation potential in patients with ischaemic cerebrovascular disease (CVD) is unclear. We assessed patients within 4 weeks of TIA or ischaemic stroke (baseline), and then 14 days (14d) and >90 days (90d) after altering antiplatelet therapy. Thrombin generation was assessed in platelet poor plasma. Ninety-one patients were recruited. Twenty-four were initially assessed on no antiplatelet therapy, and then after 14d ( N = 23) and 90d ( N = 8) on aspirin monotherapy; 52 were assessed on aspirin monotherapy, and after 14 and 90 days on aspirin and dipyridamole combination therapy; 21 patients were assessed on aspirin and after 14 days ( N = 21) and 90 days ( N = 19) on clopidogrel. Peak thrombin generation and endogenous thrombin potential were reduced at 14 and 90 days ( p ≤ 0.04) in the overall cohort. We assessed the impact of individual antiplatelet regimens on thrombin generation parameters to investigate the cause of this effect. Lag time and time-to-peak thrombin generation were unchanged at 14 days, but reduced 90 days after commencing aspirin ( p ≤ 0.009). Lag time, peak thrombin generation and endogenous thrombin potential were reduced at both 14 and 90 days after adding dipyridamole to aspirin ( p ≤ 0.01). Lag time was reduced 14 days after changing from aspirin to clopidogrel ( p = 0.045), but this effect was not maintained at 90 days ( p = 0.2). This pilot study did not show any consistent effects of commencing aspirin, or of changing from aspirin to clopidogrel on thrombin generation potential during follow-up. The addition of dipyridamole to aspirin led to a persistent reduction in peak and total thrombin generation ex vivo, and illustrates the diverse, potentially beneficial, newly recognised 'anti-coagulant' effects of dipyridamole in ischaemic CVD. [ABSTRACT FROM AUTHOR]

Background: Post-splenectomy infection has a mortality rate of up to 70%. Previously we have published data confirming the poor adherence to best practice guidelines with relation to management of the asplenic patient. A defined protocol of care was established, staff education commenced and a 'patient information leaflet' made available. Aim: To ascertain whether management of the asplenic patient has improved since the implementation of a structured programme of care. Method: Retrospective chart review of all splenectomies performed in Beaumont Hospital between 2002 and 2008. Results: Overall, 75.9% of patients were documented as having received the recommended vaccinations. Of these, 48.7% were not timed according to recommended guidelines. Prophylactic antibiotics were documented as prescribed in all but five patients discharged. Conclusions: These results demonstrate an improvement in post-splenectomy care between 2002 and 2008. However, further improvements are necessary. [ABSTRACT FROM AUTHOR]

ims: Our initial results with isolated limb perfusion (ILP) using melphalan ± TNF alpha in patients with unresectable melanoma of the limb were analyzed. Methods: 15 ILPs were performed between 2001 and 2006. Indications for ILP were stage III or IV metastatic melanoma. Complete and partial response rates, time to local and systemic tumour progression rates, disease free and overall survival rates were retrospectively analyzed. Results: Overall response rate was 93%, with a 67% complete response and a 26% partial response rate. In eight cases grade II, while in six cases grade III local toxicity was detected. However, one mortality was detected in the early postoperative phase due to a grade V complication. With a mean follow-up period of 2.7 years, eight patients had local progression and in four of those, systemic progression was detected. Conclusions: ILP was generally well tolerated and limb salvage was achieved in all cases. [ABSTRACT FROM AUTHOR]

This study explores water sorption, hygroscopic expansion, mechanical strength and ion release from the experimental amorphous calcium phosphate (ACP) composites formulated for application as endodontic sealers. Light-cure (LC) and dual-cure (DC; combined light and chemical cure) resins comprised urethane dimethacrylate (UDMA), 2-hydroxyethyl methacrylate (HEMA), methacryloyloxyethyl phthalate (MEP) and a high molecular mass oligomeric co-monomer, poly(ethyleneglycol)-extended UDMA (PEG-U) (designated UPHM resin). To fabricate composites, a mass fraction of 60% UPHM resin was blended with a mass fraction of 40% as-made (am-) or ground (g-) ACP. Glass-filled composites were used as controls. Both DC and LC ACP UPHM composites exhibited relatively high levels of water sorption accompanied by a significant hygroscopic expansion. The latter may potentially be useful to offset high polymerization stresses that develop in these materials. Ion release profiles of the experimental materials confirmed their potential for regeneration of mineral-deficient tooth structures. Their moderate to low mechanical strength after 3 months of aqueous immersion did not diminish the enthusiasm for the proposed use as endodontic sealers. For that application, DC g-ACP composites appear to be the most adequate, but micro-leakage and quantitative leachability studies are needed to fully establish their suitability. [ABSTRACT FROM AUTHOR]

Background: The association between cancer, major surgery and venous thromboembolism (VTE) is well established. Multimodal therapy is increasingly being used as standard treatment for localised gastrointestinal cancer. The aim of this study was to examine the markers of pro-coagulation response and VTE risk in an exemplar multimodal model of pre-operative combination chemotherapy and radiation therapy, followed by complex cancer surgery.Methods: Consecutive patients (n=36) with localised oesophageal cancer were studied at baseline after the first and second cycles of chemoradiation, and on post-operative days 1-28, and at 3, 6 and 9 months. Factors regulating the pro- and anti-coagulant response, as well as pro-inflammatory markers including NFkappaB activation in peripheral blood mononuclear cells, were examined. All patients received enoxaparin 40 mg s.c. postoperatively up to discharge, and underwent pulmonary CT-pulmonary angiography and venography on day 10 postoperatively.Results: Four (11%) non-fatal thromboembolic events were documented, all after hospital discharge. Neoadjuvant therapy before surgery activated factor VIII (FVIII) and pro-inflammatory NFkappaB, and increased D-dimers, pro-thrombin fragment 1+2 (F1+2) and the thrombin-anti-thrombin complex (TAT). Surgery significantly (P<0.05) increased pro-thrombin time (PT), activated partial thromboplastin time, fibrinogen, D-dimers, TAT, F1+2 and FVIII up to 6 months.Conclusion: These data highlight the linked pro-coagulant and immunoinflammatory pathways in the multimodal management of oesophageal cancer, and suggest that the duration of current standard thromboprophylaxis regimens warrants further study. [ABSTRACT FROM AUTHOR]

A pragmatic approach that balances the benefit of a whole-genome association (WGA) experiment against the cost of individual genotyping is to use pooled genomic DNA samples. We aimed to determine the feasibility of this approach in a WGA scan in rheumatoid arthritis (RA) using the validated human leucocyte antigen (HLA) and PTPN22 associations as test loci. A total of 203 269 single-nucleotide polymorphisms (SNPs) on the Affymetrix 100K GeneChip and Illumina Infinium microarrays were examined. A new approach to the estimation of allele frequencies from Affymetrix hybridization intensities was developed involving weighting for quality signals from the probe quartets. SNPs were ranked by z-scores, combined from United Kingdom and New Zealand case–control cohorts. Within a 1.7 Mb HLA region, 33 of the 257 SNPs and at PTPN22, 21 of the 45 SNPs, were ranked within the top 100 associated SNPs genome wide. Within PTPN22, individual genotyping of SNP rs1343125 within MAGI3 confirmed association and provided some evidence for association independent of the PTPN22 620W variant (P=0.03). Our results emphasize the feasibility of using genomic DNA pooling for the detection of association with complex disease susceptibility alleles. The results also underscore the importance of the HLA and PTPN22 loci in RA aetiology.Genes and Immunity (2007) 8, 57–68. doi:10.1038/sj.gene.6364359; published online 7 December 2006 [ABSTRACT FROM AUTHOR]

Venous thromboembolism (VTE) is responsible for an estimated 25 000 deaths per annum in UK hospital practice. It is well established that many of these deaths could be prevented through the use of appropriate thromboprophylaxis. This issue is of particular relevance in oncology practice, where the risks of VTE and bleeding are both significantly higher than those observed in general medical patients. Cancer patients with in-dwelling central venous catheters (CVCs) are at particularly high risk of developing thrombotic complications. However, the literature has produced conflicting conclusions regarding the efficacy of using routine primary thromboprophylaxis in these patients. Indeed such is the level of confusion around this topic, that the most recent version of the American College of Chest Physicians (ACCP) guidelines published in 2004 actually reversed their previous recommendation (published in 2001). Nevertheless, minidose warfarin continues to be routinely used in many oncology centres in the UK. In this article, we have performed a systematic review of the published literature regarding the efficacy and the risks, associated with using thromboprophylaxis (either minidose warfarin or low-dose LMWH) in cancer patients with CVC. On the basis of this evidence, we conclude that there is no proven role for using such thromboprophylaxis. However, asymptomatic CVC-related venous thrombosis remains common, and further more highly powered studies of better design are needed in order to define whether specific subgroups of cancer patients might benefit from receiving thromboprophylaxis. [ABSTRACT FROM AUTHOR]

While a number of virus-based delivery schemes have been developed for myocardial gene transfer, no technique has proven capable of modifying a majority of cardiac myocytes rapidly and homogeneously in the in vivo rat model, and most schemes result in significant infection of the liver and other organs. However, adenoviral delivery to the excised heart during retrograde perfusion can produce 67–92% efficient gene transfer. In this study, we adapt this isolation/perfusion scheme to the heart in vivo. We isolated the heart in vivo by simultaneously clamping all vessels to/from the heart. The heart was then continuously retrograde perfused through a catheter positioned in the aortic root. A second catheter in the right ventricle provided a path for efflux. After perfusing the heart for 7.5 min with calcium-free Tyrode solution followed by 90 s no-flow viral exposure (AdV.cmv.LacZ; 1012 viral particles/ml), gene transfer efficiency was 60% compared to 5% by a conventional cross-clamp technique. Infection of peripheral organs was dramatically reduced. Given the prevalence of the rat in so many models of heart disease, this enhancement of infection represents an advancement in viral-based delivery of exogenous genes to heart for the study of gene therapy in vivo.Gene Therapy (2005) 12, 958–964. doi:10.1038/sj.gt.3302477 Published online 24 March 2005 [ABSTRACT FROM AUTHOR]

Overwhelming post-splenectomy infection (OPSI) has a 50–70% mortality rate and carries a lifetime risk for the asplenic patient. Specific British guidelines have been developed to reduce its incidence. To determine whether British guidelines were being followed in our own institution and what impact they had on overwhelming post-splenectomy infection. Retrospective chart review of 100 splenectomies performed by Department of Surgery, Beaumont Hospital from January 1990 to January 2000. Twenty per cent of patients were discharged without any recommended vaccinations. Prophylactic antibiotics were not prescribed in 53% of patients. Just 12% of charts document a verbal explanation of the complications and management of asplenia to the patient. Overall septic mortality was 12%, of whom 8% died in hospital and 4% after discharge. Management of the asplenic patient has improved but is far from complete. A central register of asplenic patients and national asplenic guidelines should be established in Ireland to ensure optimum patient care. [ABSTRACT FROM AUTHOR]

Patients with advanced MDS and secondary AML respond poorly to chemotherapy. Granulocyte-macrophage colony-stimulating factor (GM-CSF) can stimulate proliferation of leukemic blasts and sensitize these cells to the cytotoxic effects of S-phase-specific drugs. This is the first report of safety and efficacy of GM-CSF prior to and during cytarabine in a lowdose, intermittent regimen for elderly patients with poor risk acute myelogenous leukemia or myelodysplastic syndrome. Twenty patients, age 68 to 86 years, each received 250 μg/m² of GM-CSF (Sargramostatin; Immunex, Seattle, WA, USA) subcutaneously (s.c.) or intravenously (i.v.) for 3 days followed by GM-CSF at the same dose and cytarabine 100 mg/m² i.v, for 3 days. GM-CSF and cytarabine were both administered for 3 days during weeks 2 and 3 followed by a 3-week rest period. Rates of CR and PR were 20% and 40%, respectively. These included clinically significant resolution of cytopenias and transfusion requirements. Many of the responding patients had been heavily pretreated prior to enrollment. One- and 2-year survival estimates are 44% and 19%, respectively. Myelosuppression was the most significant toxicity. Our findings suggest that this novel combination of GM-CSF with sequential and concomitant low-dose cytarabine can benefit patients with poor risk myeloid malignancies. [ABSTRACT FROM AUTHOR]

A Regular morbidity and mortality conference has been conducted over a period of 18. months. The conference has been a useful forum for postgraduate surgical education and continuous assessment of surgical trainees. The data from each conference have been combined to provide a comprehensive audit of general surgery at a busy teaching hospital. [ABSTRACT FROM AUTHOR]

Ten operations for angio access for other than haemodialysis were performed in eight patients. A vascular prosthesis was used in all cases to construct an arterio-venous shunt. Five different anatomic sites of implantation were required, and angio access was provided in all cases. We describe the operative techniques and results, and comment on special problems encountered in these patients. [ABSTRACT FROM AUTHOR]

Two cases in which digital arteritis antedated malignant disease are reported. The literature concerning this rare association is reviewed. Cryoimmunoglobulinaemia is suggested as a possible mechanism for digital arteritis. [ABSTRACT FROM AUTHOR]

Carcinoma of the bile ducts can be a problem from the diagnostic point of view and from that of treatment. Active intervention is nearly always worthwhile, providing short-term relief of symptoms when palliative by-pass is used and offering the prospect of long term survival in cases where radical resection is undertaken. [ABSTRACT FROM AUTHOR]

A CASE of malignant insulinoma was treated with streptozotocin intravenously and by coeliac axis infusion. Treatment was repeated over a period of two years, and the total dose was 82.5g. Several clinical remissions of hypoglycaemia were obtained despite the persistence of abnormally elevated plasma insulin levels. At necropsy tumour metastases within the liver were not necrotic. Severe medial degeneration of the lower abdominal aorta was present but the relationship of this change to intra-arterial infusion of the drug could not be established. [ABSTRACT FROM AUTHOR]

We describe a patient with longstanding steroid-dependent systemic lupus erythematosus (SLE) in whom clinical and serological remission was achieved following high-dose therapy and autologous bone marrow rescue for high-grade non-Hodgkin’s lymphoma. However, 3 years later, autoimmune disease re-presented in the form of immune thrombocytopenia (ITP), which had not previously been a feature of the SLE, necessitating reintroduction of steroid immunosuppression. Relapse of SLE is most likely, although de novo ITP post-BMT is also a possibility. The case suggests that severe longstanding autoimmune disease may be controlled by high-dose therapy and autologous stem cell reconstitution. However, further studies are required to determine the mechanism of re-emergence of autoimmunity and to evaluate optimal regimens and the potential value of such therapy in severe autoimmune diseases. [ABSTRACT FROM AUTHOR]

Objective: In a multicentre, double-blind, parallel group study, the anti-anginal and the anti-ischaemic efficacy of 12 weeks of therapy with the vasodilating β-adrenoceptor-blocker carvedilol 25 mg b.i.d. was compared with verapamil 120 mg t.i.d. Methods: During a 2-week placebo run-in period, patients were required to have two treadmill exercise tests (modified Bruce Protocol) differing by not more than 15% with regard to total exercise time (TET). Of 313 patients enrolled, 248 were randomized and 212 completed the study according to the protocol. Results: The primary variable TET was analysed using the Cox Proportional Hazards Model to take into account censored values due to the patient stopping the exercise test for reasons other than angina. Forty-three per cent of patients allocated to carvedilol and 36% to verapamil did not stop with angina at the final visit. There was no difference in the TET between the groups, the risk ratio being 1.14 in favour of carvedilol (90% CI 0.85–1.52). TET increased from 378 s at baseline to 436 s at the final visit in the carvedilol group and from 386 to 438 s in the verapamil group. Results for time to angina and time to 1 mm ST-segment depression were similar. Compared to verapamil, carvedilol significantly reduced HR, systolic BP and rate pressure product at peak exercise. Analysis of 48 h Holter monitor data showed a greater reduction of HR and PVCs with carvedilol. Lown grading improved in both groups. Adverse events were reported by 48% (3.2% serious adverse events) of patients taking carvedilol and 58% (5.7% serious adverse events) taking verapamil. Conclusion: Carvedilol is at least as effective as verapamil in the management of chronic stable angina and demonstrated a favourable adverse event profile. [ABSTRACT FROM AUTHOR]

Ninety-six consecutive above-knee femoropopliteal bypasses, using polytetrafluoroethylene (PTFE) preferentially, were performed for limb-threatening ischaemia. Cumulative primary graft patency was 68 per cent, 49 per cent and 36 per cent and limb salvage 93 per cent, 85 per cent and 75 per cent at 1, 3 and 5 yr respectively. As a result of poor long term survival (51 per cent at 5 yr), and the healing of remedial lesions before graft occlusion, 68 patients (72 per cent) required no further intervention. Eighteen secondary bypasses were undertaken, 12 using ipsilateral saphenous vein. In this group of elderly patients with poor life expectancy, where a limited operation is desirable, the use of PTFE provided excellent limb salvage with low morbidity. Although we can no longer justify our continued use of PTFE in every case of critical ischaemia because of its inferior patency to autogenous vein, we continue to use it preferentially in patients whose lifespan is likely to be short and in cases where a remedial lesion is present. [ABSTRACT FROM AUTHOR]

The increased risk of sepsis in patients following splenectomy has been well documented. Fear of over-whelming post-splenectomy sepsis (OPSI) has resulted in a generalised trend towards splenic salvage among surgeons. However, splenorrhaphy and attempts at splenic salvage may of themselves predispose to significant morbidity, sometimes more serious than increased susceptibility to infection associated with splenectomy. This study aims to assess the risk of splenectomy and subsequent asplenia. We reviewed 246 patients who underwent splenectomy over a 16 year period. Indications for splenectomy were considered under the following headings: haematological (N = 116), trauma (N = 69), visceral carcinoma (N = 28), incidental (N = 13) and miscellaneous (N = 20). There were 28 deaths in the series, primarily among those in the intra-abdominal carcinoma (13) and multiple trauma (13) groups. Two deaths were recorded among patients undergoing elective splenectomy for benign disease. Thrombo-embolic complications were recorded in nine patients; respiratory tract infection in 36 patients and intra-abdominal abscess in two patients. Two cases of post-splenectomy pneumococcal septicaemia were documented, neither of which was fatal. While not an entirely benign procedure, splenectomy can be performed relatively safely, especially when performed for benign disease in an adult population. [ABSTRACT FROM AUTHOR]

A structural study of glass-ionomer cement (GIC) dental restoratives has been completed. Transmission electron microscopy, selected area electron diffraction, and X-ray diffraction studies indicate domain-like microstructure in a new experimental material, whereas a featureless amorphous gel-like microstructure exists in the conventional GIC. Nuclear magnetic resonance studies were also conducted. The new experimental GIC contains domains of (i) bonelike material (apatite), (ii) mesoporous material and (iii) other framework structures (aluminium phosphate in the high cristobalite structure), with its setting chemistry a restructuring of the aluminosilicate glass around the template of poly(acrylic acid). Conventional glass-ionomer cement may set by a similar but slower process. Leaching properties of glass-ionomer cements are also explained. [ABSTRACT FROM AUTHOR]

The influence of elevated Mg (20 mM) on mechanical response, fibre electrolyte composition and Ca-exchange, as a function of external Ca concentration, has been studied in an isolated trabecular muscle column of rat ventricle. At [Ca] 2.5 mM, cellular Mg-content increased in 20 mM [Mg] without effect on contractility or fibre content of other electrolytes. As [Ca] was reduced from 2.5 mM, 20 mM Mg caused progressive inhibition of contractile response of muscle to electrical stimulation. In both resting and stimulated trabeculae the intrafibre Mg-content rapidly increased and Ca-content fell in the initial 20 min incubation in reduced (1.5 or 0.75 mM) Ca, as the contractile response declined. Subsequent restoration of [Ca] to 2.5 mM restored contractile response in the presence of high Mg concentration. Exposure of trabeculae to high Mg also caused a significant decrease in 45-Ca exchange in a muscle calcium-pool exchanging with t1/2 7 min when [Ca] was 1.5 mM, but had no effect on Ca-exchange when [Ca] was 2.5 mM. The effect of high Mg on exchange of Ca indicated that displacement of a fraction of superficially-bound muscle Ca was responsible for the diminished contractile response in Mg-loaded trabeculae. [ABSTRACT FROM AUTHOR]

The membrane stabilizer diphenylhydantoin (DPH) did not alter the net content of Na, K, Ca or Mg in frog sartorius muscle freshly incubated or actively transporting Na and K following Na-loading and K-depletion. Resting influx of K from normal Ringer was significantly reduced by DPH, and this inhibition occurred in the ouabain-insensitive K-uptake. Inhibition of K-influx by DPH was overcome when [K] was raised to 10 mM, and Rb-influx was not sensitive to the inhibitor in 2.5 mM Rb-Ringer. Efflux of tracer K was reduced by DPH in the presence and absence of ouabain. Exchange of muscle Na was not affected under condit in which K-exchange was significantly reduced, but DPH appeared to cause increased net loss of Na from muscles washed in Na-free medium. The inhibition by DPH of resting K-exchange was not sensitive to wide variations in [Na] or in [Ca]. The results suggest that the effect of DPH on frog skeletal muscle in normal ionic environment is to reduce the resting, passive component of K-exchange across the fibre membrane. This effect is discussed in relation to the membrane stabilizing actions of diphenylhydantoin. [ABSTRACT FROM AUTHOR]

The penetration of magnesium from high-Mg Ringer's solution into skeletal muscle, and accompanying effects on intrafibre electrolyte composition, muscle contractility and Ca-exchange have been studied in isolated preparations of whole sartorius of Rana temporaria. Muscle magnesium, corrected for extracellular space, rose rapidly and then more slowly, and at 60 min in 20 mM Mg-Ringer it was calculated that intrafibre unbound Mg was increased by at least two-fold over the level in companion muscles in normal Ringer. Contractile response to direct, supramaximal stimulation was reduced in Mg-loaded muscles while resting membrane potential ( E) remained unaffected. Contracture in response to high-K was diminished while caffeine contracture was not changed. Muscles loaded with Mg also showed significant loss of fibre K and gained Na. Mg-loading caused a significant decrease in exchangeability of muscle Ca. Three fractions of exchangeable Ca in muscle were detected, characterised by half-times of circa 1.5, 7 and 50 min, respectively. In muscles soaked in high-Mg Ringer the half-times for these fractions were not different to the controls, but the quantities exchanged in the two slower fractions were reduced. [ABSTRACT FROM AUTHOR]

A low temperature ESR technique has been developed for the observation of free radical intermediates generated in clear polymer films during photolysis by UV light under nitrogen. The technique is simple and reproducible, and can be used for polymers having glass transition temperatures at or about room temperature without the need to employ spin traps. The generation of free radicals can be monitored and quantified during exposure, and the radical yields obtained can then be correlated with the chemical structure of the polymer to provide a rapid predictive evaluation of the exterior durability of the polymer. [ABSTRACT FROM AUTHOR]

The solid-state C NMR spectra of a 99% cis-1,4-polybutadiene after γ-irradiation at 25°C showed a reduction in the intensity of the -CH=resonance at 130.1 ppm and the development of a broad resonance at 45.8 ppm due to H-crosslinks. The -CH-signal comprises the original narrow resonance at 28.2 ppm due to -CH-groups remote from crosslinks, and a broad resonance centred at 30.5 ppm attributable to -CH-groups adjacent to crosslinks. There was an increase in the intensity of the -CH-resonance at 33.6 ppm due to trans -CH-groups resulting from radiation-induced isomerization. Quantitative determinations of (i) the decrease in -CH= and (ii) the increase in crosslinked carbon atoms both gave G values of about 14 after 3 MGy. The crosslinks are evidently located in clusters, since literature G(X) values derived from gel contents and swelling ratios range from 3 to 6. The high G(X) value from NMR is consistent with a chain reaction for the crosslinking process. [ABSTRACT FROM AUTHOR]

The high resolution C NMR spectrum of Kapton in sulfuric acid solution is reported. Assignments to the spectrum were made by comparison with non-proton-decoupled spectra, and with improved solid-state spectra. The solid-state spectrum of the reprecipitate from a HSO solution showed that no change in the chemical structure of Kapton occurred during dissolution, but that the regular morphology present in the original film had been disrupted. [ABSTRACT FROM AUTHOR]

The compositions of copolymers of butadiene (B) and isoprene (I), produced by anionic copolymerization with sec-butyl lithium initiator in hexane at 20-40°C gave a good fit at low conversions to the terminal model for copolymerization. Non-linear, 'best estimates' of the reactivity ratios r and r were 2.82 and 0.42, 1.72 and 0.36, 2.18 and 0.35 at 20, 30 and 40°C. The rates of copolymerization at conversions up to 98% of total monomer gave a smooth relationship with the instantaneous feed composition, calculated using the terminal model, at each temperature and independent of the initial feed composition. These results are in accord with the terminal model being applicable to this anionic copolymerization from low to hiqh conversions. [ABSTRACT FROM AUTHOR]

The confluence of enhanced attention to primary care and palliative care education presents educators with an opportunity to improve both (as well as patient care) through integrated teaching. Improvements in palliative care education will have benefits for dying patients and their families, but will also extend to the care of many other primary care patients, including geriatric patients and those with chronic illnesses, who make up a large proportion of the adult primary care population. In addition, caring for the dying, and teaching others to carry out this task, can be an important vehicle for personal and professional growth and development for both students and their teachers. [ABSTRACT FROM AUTHOR]

A method of estimating antiplasmin levels in human serum is described. Antiplasmin activity is stable at room temperature for 24 hours. The diurnal variations of antiplasmin parallel the 10% clot lysis time. The hour to hour and day to day variation is slight in normal individuals. The normal range of antiplasmin activity is from 50% to 300% with most values falling between 100% and 150%. The age of the individual does not influence the antiplasmin level. In neoplastic disease and cardiovascular disease antiplasmin activity is considerably increased in some cases. It is suggested that antiplasmin activity is of clinical importance in patients with neoplastic disease, rheumatoid arthritis, arteriosclerosis and possibly disseminated sclerosis. [ABSTRACT FROM AUTHOR]

For many years, it has been recognised that venous thrombo-embolism (VTE) represents a common complication of malignancy. Moreover, VTE in the form of pulmonary embolism (PE) is life-threatening, and constitutes the second leading cause of death in patients with cancer. Consequently, overall survival is significantly reduced in cancer patients who develop thrombosis. In addition, treatment of VTE with anticoagulation is often difficult to manage in the context of cancer. Studies have shown that the risk of recurrent VTE, and the risk of major bleeding are both increased significantly in cancer patients on therapeutic anticoagulant therapy. In this case report, we describe a patient with metastatic carcinoma of the cervix, who developed recurrent thrombotic complications despite being maintained on standard therapeutic doses of both warfarin, and subsequently low molecular weight heparin. However, her refractory VTE was successfully managed using a supra-therapeutic dose low-molecular-weight-heparin (LMWH) regimen, together with close monitoring of plasma anti-Xa levels. [ABSTRACT FROM AUTHOR]

Raised percentage hypochromic red cells (%HRC) were detected at diagnosis in 10 of 34 consecutive patients with low-risk myelodysplastic syndrome (MDS) [refractory anemia (RA) (4/26) and RA with ring sideroblasts (6/8)], all of whom had normal or increased serum ferritin and bone marrow iron stores. Elevated %HRC has persisted in all 10 cases and subsequently developed in another RA patient who later had a complete remission of MDS with normalisation of %HRC after a respiratory tract infection. A strong positive correlation was found between %HRC and erythrocyte zinc protoporphyrin levels in 11 MDS patients tested ( p=0.01), suggesting that functional iron deficiency contributes to ineffective erythropoiesis in cases of MDS with raised %HRC. Five of seven patients with elevated %HRC had satisfactory haemoglobin responses to a trial of human recombinant erythropoietin without iron supplementation. [ABSTRACT FROM AUTHOR]

Investigation of lower extremity pain is compromised by comorbid disorders that may interfere with conventional testing. To compare pedal ergometry with conventional treadmill testing. A prospective study was performed where patients presenting with a diagnosis of intermittent claudication were assessed by both methods of testing. Of 78 patients studied with both tests, no exercise-induced ankle pressure changes occurred in 26, two were unable to complete either test despite normal pressure measurements, while 24 had exercise-induced pressure drop detected by both tests. Of patients who completed pedal ergometry, 21 were unable to complete the treadmill test, 14 of whom had negative ergometry, while seven had a pressure drop detected by pedal ergometry. Three had pressure changes with pedal ergometry, but not with treadmill testing and two had pressure changes on the treadmill not reproduced by pedal ergometry. Pedal ergometer is more sensitive than treadmill testing in detecting arterial insufficiency, as indicated by a 20% or greater fall in ankle pressure, and more suitable in a subgroup of patients unable to tolerate conventional treadmill testing. [ABSTRACT FROM AUTHOR]

A non-invasive programme of post-operative surveillance and intervention where necessary is essential to optimise results with arterial reconstruction. We report our experience with duplex ultrasonography in the follow-up lower limb arterial bypass grafts. One hundred and three duplex studies were performed in 58 patients with 59 lower limb arterial bypass grafts. Grafts were visualised throughout their length and haemodynamic characteristics including peak systolic velocity (PSV) were measured. Angiography was performed on the basis of any significant anatomical or haemodynamic abnormality on duplex. AH grafts were visualised throughout their length with ease. Satisfactory visualisation of 86% of anastomoses was achieved. PSV was found to be the most easily reproducible haemodynamic index and the best indicator of graft function. PSV had a median value of 79 cm/sec and a range of 51-117 cm/sec in normal grafts compared to 26 cm/sec (range 19-42 cm/sec) in grafts with stenosis. Twelve pre-occlusive lesions which were not evident clinically, 5 within and 7 outside the graft, have been detected. Eight have been treated by transluminal angioplasty. Two grafts with stenosis and PSVs of less than 25 cm/sec had occluded by the time angiography was performed 2 weeks later. Duplex is an excellent, non-invasive, and repeatable method of screening of grafts at risk of failure, allowing earlier intervention with improved secondary patency. [ABSTRACT FROM AUTHOR]

Repair of abdominal aortic aneurysms (A A A) is being performed with a progressively lower mortality and morbidity. We reviewed 111 patients who underwent repair of their AAA. Sixty-two were electively repaired and 49 had emergency surgery. Eight patients had cocomitant non-vascular procedures carried out. Operative mortality was 3.2 % and 49 % for elective and emergency cases respectively. Postoperative complications occurred in 40% of elective cases and 72% of emergency cases, respiratory complications being the most common, occurring in 25% and 40% of elective and emergency cases respectively. Subsequent graft complications occurred in six patients, five following emergency surgery. [ABSTRACT FROM AUTHOR]

B19 parvovirus infection is a principal cause of transient bone marrow suppression in patients with chronic haemolytic anaemias. Acute infection is described in a family of five individuals with hereditary spherocytosis; three of them developed marked hypoplastic anaemia. [ABSTRACT FROM AUTHOR]

Ninety-three consecutive treadmill exercise stress tests were performed for the assessment of peripheral vascular function. Thirty-one were for atypical claudication-like symptoms including pain on standing, relief on sitting and back pain. Pedal pulses were palpable in 24 patients. Twentyfive patients (81%) had a negative stress test, suggesting a non-vascular aetiology and this finding was subsequently confirmed in 24 of the 25. The final diagnoses were spinal stenosis 13, [CT = 3, myelogram = 5, neurosurgeon opinion = 4, MRI = 1], myositis 2, restless leg syndrome 2 and osteoarthritis 7. Four patients had symptoms due to a combination of peripheral occlusive arterial disease and spinal stenosis; the latter was considered the predominant disorder in all four. Of the original 31 patients with atypical symptoms, spinal stenosis was present in 13 (42%). Atypia - in the common syndrome of intermittent claudication should alert the surgeon to the possibility of spinal canal disorders. Further investigation may identify significant pathology spinal stenosis in particular. [ABSTRACT FROM AUTHOR]

This article describes a 22 year experience of a general surgical unit in the treatment of infantile hypertrophic pyloric stenosis (I HPS). The hospital course of 229 IHPS patients is reviewed. The male:female ratio was 3.6:1, median age 6 weeks (range 2-26 weeks) with a positive family history in 8.3%. The diagnosis of IHPS was established clinically by palpation of a 'pyloric tumour' during a pre operative test meal/clinical examination in 92.6%; in the remainder, the diagnosis was made radiologically. Ramstedt's pyloromyotomy was performed within 5 days of admission in 74% of patients and within 10 days of admission in 89%. The median post-operative hospital stay was 10 days (range 3-60 days). Wound morbidity occurred in 10.0% - wound infection (7.3%) and wound dehiscence (2.6%). However, wound morbidity was reduced in the second half of the series, partly by greater utililisation of non-absorbable suture in place of chromic catgut for wound closure. Mucosal penetration was suspected in 14.8% of cases. Repeat pyloromyotomy was necessary in 1.3%. One baby died (0.4%) - this was in the early part of the series and was directly attributable to fluid and electrolyte disorder. We conclude that Ramstedt's pyloromyotomy for infantile hypertrophic pyloric stenosis can be performed with acceptable morbidity and minimal mortality in a general surgical unit. [ABSTRACT FROM AUTHOR]