Colon cancer survival in the elderly without curative surgery

INTRODUCTION

The aim of this study was to chart the natural history of elderly patients with colon cancer who are managed nonoperatively, with the primary outcome being life expectancy from diagnosis to death.

METHODS

This was a retrospective analysis of patients aged 80 years and above diagnosed with colon cancer in a tertiary care referral hospital in England between 1 January 2012 and 31 December 2017.

RESULTS

Thirty-two patients were diagnosed with non-metastatic colon cancer and managed non-operatively. The median age of patients in this study was 86 years. The group had a median Charlson Comorbidity Index of 7 (range 6-12) and the median frailty score was 6 (range 3-8). Progression to metastatic disease was identified in two patients; two further patients showed locoregional progression of cancer and therefore required palliative surgical intervention. Survival of these patients ranged from 105 to 1,782 days with a median life expectancy of 586 days. Place of death was identified in 15/31 patients: 4 (27%) died in hospital, 12 (38%) died at home and 15 (47%) died in a nursing or residential home; data were missing for 1 patient (3%).

CONCLUSIONS

Nonoperative management of elderly patients with colon cancer yields reasonable life expectancy and a low risk of life-threatening local complications.

REVISE: re-evaluating the inhibition of stress erosions in the ICU-statistical analysis plan for a randomized trial

BACKGROUND

The REVISE (Re-Evaluating the Inhibition of Stress Erosions in the ICU) trial will evaluate the impact of the proton pump inhibitor pantoprazole compared to placebo in invasively ventilated critically ill patients.

OBJECTIVE

To outline the statistical analysis plan for the REVISE trial.

METHODS

REVISE is a randomized clinical trial ongoing in intensive care units (ICUs) internationally. Patients ≥ 18 years old, receiving invasive mechanical ventilation, and expected to remain ventilated beyond the calendar day after randomization are allocated to either 40 mg pantoprazole intravenously or placebo while mechanically ventilated.

RESULTS

The primary efficacy outcome is clinically important upper GI bleeding; the primary safety outcome is 90-day mortality. Secondary outcomes are ventilator-associated pneumonia, Clostridioides difficile infection, new renal replacement therapy, ICU and hospital mortality, and patient-important GI bleeding. Tertiary outcomes are total red blood cells transfused, peak serum creatinine concentration, and duration of mechanical ventilation, ICU, and hospital length of stay. Following an interim analysis of results from 2400 patients (50% of 4800 target sample size), the data monitoring committee recommended continuing enrolment.

CONCLUSIONS

This statistical analysis plan outlines the statistical analyses of all outcomes, sensitivity analyses, and subgroup analyses. REVISE will inform clinical practice and guidelines worldwide.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov NCT03374800. November 21, 2017.

REVISE: Re-Evaluating the Inhibition of Stress Erosions in the ICU: a randomised trial protocol

INTRODUCTION

The Re-Evaluating the Inhibition of Stress Erosions (REVISE) Trial aims to determine the impact of the proton pump inhibitor pantoprazole compared with placebo on clinically important upper gastrointestinal (GI) bleeding in the intensive care unit (ICU), 90-day mortality and other endpoints in critically ill adults. The objective of this report is to describe the rationale, methodology, ethics and management of REVISE.

METHODS AND ANALYSIS

REVISE is an international, randomised, concealed, stratified, blinded parallel-group individual patient trial being conducted in ICUs in Canada, Australia, Saudi Arabia, UK, US, Kuwait, Pakistan and Brazil. Patients≥18 years old expected to remain invasively mechanically ventilated beyond the calendar day after enrolment are being randomised to either 40 mg pantoprazole intravenously or an identical placebo daily while mechanically ventilated in the ICU. The primary efficacy outcome is clinically important upper GI bleeding within 90 days of randomisation. The primary safety outcome is 90-day all-cause mortality. Secondary outcomes include rates of ventilator-associated pneumonia, Clostridioides difficile infection, new renal replacement therapy, ICU and hospital mortality, and patient-important GI bleeding. Tertiary outcomes are total red blood cells transfused, peak serum creatinine level in the ICU, and duration of mechanical ventilation, ICU and hospital stay. The sample size is 4800 patients; one interim analysis was conducted after 2400 patients had complete 90-day follow-up; the Data Monitoring Committee recommended continuing the trial.

ETHICS AND DISSEMINATION

All participating centres receive research ethics approval before initiation by hospital, region or country, including, but not limited to - Australia: Northern Sydney Local Health District Human Research Ethics Committee and Mater Misericordiae Ltd Human Research Ethics Committee; Brazil: Comissão Nacional de Ética em Pesquisa; Canada: Hamilton Integrated Research Ethics Board; Kuwait: Ministry of Health Standing Committee for Coordination of Health and Medical Research; Pakistan: Maroof Institutional Review Board; Saudi Arabia: Ministry of National Guard Health Affairs Institutional Review Board: United Kingdom: Hampshire B Research Ethics Committee; United States: Institutional Review Board of the Nebraska Medical Centre. The results of this trial will inform clinical practice and guidelines worldwide.

TRIAL REGISTRATION NUMBER

NCT03374800.

Incisional hernia following colorectal cancer surgery according to suture technique: Hughes Abdominal Repair Randomized Trial (HART)

BACKGROUND

Incisional hernias cause morbidity and may require further surgery. HART (Hughes Abdominal Repair Trial) assessed the effect of an alternative suture method on the incidence of incisional hernia following colorectal cancer surgery.

METHODS

A pragmatic multicentre single-blind RCT allocated patients undergoing midline incision for colorectal cancer to either Hughes closure (double far-near-near-far sutures of 1 nylon suture at 2-cm intervals along the fascia combined with conventional mass closure) or the surgeon's standard closure. The primary outcome was the incidence of incisional hernia at 1 year assessed by clinical examination. An intention-to-treat analysis was performed.

RESULTS

Between August 2014 and February 2018, 802 patients were randomized to either Hughes closure (401) or the standard mass closure group (401). At 1 year after surgery, 672 patients (83.7 per cent) were included in the primary outcome analysis; 50 of 339 patients (14.8 per cent) in the Hughes group and 57 of 333 (17.1 per cent) in the standard closure group had incisional hernia (OR 0.84, 95 per cent c.i. 0.55 to 1.27; P = 0.402). At 2 years, 78 patients (28.7 per cent) in the Hughes repair group and 84 (31.8 per cent) in the standard closure group had incisional hernia (OR 0.86, 0.59 to 1.25; P = 0.429). Adverse events were similar in the two groups, apart from the rate of surgical-site infection, which was higher in the Hughes group (13.2 versus 7.7 per cent; OR 1.82, 1.14 to 2.91; P = 0.011).

CONCLUSION

The incidence of incisional hernia after colorectal cancer surgery is high. There was no statistical difference in incidence between Hughes closure and mass closure at 1 or 2 years.

REGISTRATION NUMBER

ISRCTN25616490 (http://www.controlled-trials.com).

Preparedness and response to COVID-19 in a quaternary intensive care unit in Australia: perspectives and insights from frontline critical care clinicians

OBJECTIVES

This study was conducted to explore the perspectives and opinions of intensive care unit (ICU) nurses and doctors at a COVID-19-designated pandemic hospital concerning the preparedness and response to COVID-19 and to consolidate the lessons learnt for crisis/disaster management in the future.

DESIGN

A qualitative study using in-depth interviews (IDIs) and focus group discussions (FGDs). Purposeful sampling was conducted to identify participants. A semistructured guide was used to facilitate IDIs with individual participants. Two FGDs were conducted, one with the ICU doctors and another with the ICU nurses. Thematic analysis identified themes and subthemes informing about the level of preparedness, response measures, processes, and factors that were either facilitators or those that triggered challenges.

SETTING

ICU in a quaternary referral centre affiliated to a university teaching COVID-19-designated pandemic hospital, in Adelaide, South Australia.

PARTICIPANTS

The participants included eight ICU doctors and eight ICU nurses for the IDIs. Another 16 clinicians participated in FGDs.

RESULTS

The study identified six themes relevant to preparedness for, and responses to, COVID-19. The themes included: (1) staff competence and planning, (2) information transfer and communication, (3) education and skills for the safe use of personal protective equipment, (4) team dynamics and clinical practice, (5) leadership, and (6) managing end-of-life situations and expectations of caregivers.

CONCLUSION

Findings highlight that preparedness and response to the COVID-19 crisis were proportionate to the situation's gravity. More enablers than barriers were identified. However, opportunities for improvement were recognised in the domains of planning, logistics, self-sufficiency with equipment, operational and strategic oversight, communication and managing end-of-life care.

Perceptions held by healthcare professionals concerning organ donation after circulatory death in an Australian intensive care unit without a local thoracic transplant service: A descriptive exploratory study

BACKGROUND AND OBJECTIVE

Organ donation rates continue to be low in Australia compared with demand. Donation after circulatory death (DCD) has been an important strategy to increase donation rates, facilitated by advances in cardiopulmonary support in intensive care units (ICUs). However, DCD may harbour greater logistical challenges and unfavourable perceptions amongst some ICU healthcare professionals. The aim of this study was to evaluate and understand DCD perceptions at an Australian tertiary hospital.

METHODS

This descriptive exploratory study was conducted at an Australian tertiary hospital. Participants were recruited voluntarily for interview via email and word-of-mouth through the hospital's ICU network. The study used a mixed-methods approach; five close-ended questions were included in the form of Likert scales followed by a semistructured interview with open-ended questions designed to understand participants' perceptions of DCD. Interviews were recorded, transcribed, and thematically analysed.

RESULTS

Sixteen participants were interviewed including eight intensive care doctors, four donation specialist nursing coordinators (DSNCs), and four bedside nurses. Likert responses demonstrated clinicians' support for both DCD and donation after brain death (DBD). Thematic analysis of the transcripts yielded three overarching themes including 'Contextual and environmental influences on DCD decision-making', 'Personal difficulties faced by clinicians in DCD decision-making', and 'Family influences on DCD decision-making'. Significant geographical separation between donation and organ retrieval teams, incurring significant resource utilisation, impacted the donation team's decision-making around DCD, as did a perceived disruption of ICU care to facilitate donation especially for cases where successful DCD was identified to be unlikely.

CONCLUSIONS

Overall, DCD was as acceptable to participants as DBD. However, the geographical separation of this centre meant that logistical barriers potentially impacted the DCD process. Open lines of communication with transplant centres, local resourcing, and a culture of education, experience, and leadership may facilitate the DCD programs where distant retrieval is commonplace.

Effects of Standard vs Energy-Dense Formulae on Gastric Retention, Energy Delivery, and Glycemia in Critically Ill Patients

BACKGROUND

Energy-dense formulae are often provided to critically ill patients with enteral feed intolerance with the aim of increasing energy delivery, yet the effect on gastric emptying is unknown. The rate of gastric emptying of a standard compared with an energy-dense formula was quantified in critically ill patients.

METHODS

Mechanically ventilated adults were randomized to receive radiolabeled intragastric infusions of 200 mL standard (1 kcal/mL) or 100 mL energy-dense (2 kcal/mL) enteral formulae on consecutive days in this noninferiority, blinded, crossover trial. The primary outcome was scintigraphic measurement of gastric retention (percentage at 120 minutes). Other measures included area under the curve (AUC) for gastric retention and intestinal energy delivery (calculated from gastric retention of formulae over time), blood glucose (peak and AUC), and intestinal glucose absorption (using 3-O-methyl-D-gluco-pyranose [3-OMG] concentrations). Comparisons were undertaken using paired mixed-effects models. Data presented are mean ± SE.

RESULTS

Eighteen patients were studied (male/female, 14:4; age, 55.2 ± 5.3 years). Gastric retention at 120 minutes was greater with the energy-dense formula (standard, 17.0 ± 5.9 vs energy-dense, 32.5 ± 7.1; difference, 12.7% [90% confidence interval, 0.8%-30.1%]). Energy delivery (AUC₁₂₀ , 13,038 ± 1119 vs 9763 ± 1346 kcal/120 minutes; P = 0.057), glucose control (peak glucose, 10.1 ± 0.3 vs 9.7 ± 0.3 mmol/L, P = 0.362; and glucose AUC₁₂₀ 8.7 ± 0.3 vs 8.5 ± 0.3 mmol/L.120 minutes, P = 0.661), and absorption (3-OMG AUC₁₂₀ , 38.5 ± 4.0 vs 35.7 ± 4.0 mmol/L.120 minutes; P = .508) were not improved with the energy-dense formula.

CONCLUSION

In critical illness, administration of an energy-dense formula does not reduce gastric retention, increase energy delivery to the small intestine, or improve glucose absorption or glucose control; instead, there is a signal for delayed gastric emptying.

Are point-of-care urine albumin-creatinine ratio measurements accurate in the critically ill?

BACKGROUND

In the critical care environment, elevated albuminuria values show capacity to reflect illness severity and predict mortality and hence assessing albumin/creatinine ratio (ACR) at the bedside has potential clinical benefit Point-of-care (POC) analysers offer rapid results but may be less accurate then laboratory analysis.

METHODS

Critically ill adult patients with a urinary catheter in situ had albumin, creatinine, and ACR measurements performed via laboratory and POC analysis. Data are presented as mean (standard deviation) or median [interquartile range]. Measurement agreement was assessed by Lin's concordance correlation coefficient, Bland Altman 95% limits of agreement, and classification by Cohen's kappa statistic.

RESULTS/FINDINGS

Albumin, creatinine, and ACR analysis was performed for 30 patients. Lin's correlation coefficient showed 'substantial' agreement for albumin and ACR and 'almost perfect' agreement for creatinine for POC vs laboratory analysis. POC vs laboratory analysis also showed poor agreement for identification of normal ACR (>1 mg/mmol) and mild urine ACR (1-3 mg/mmol) and 'substantial' agreement for moderately increased urine ACR (3-30 mg/mmol).

CONCLUSIONS

ACR POC values appear to provide an accurate and rapid method that has potential to provide an early indication of injury severity and mortality risk in the critically ill.

The impact on new-onset stress and PTSD in relatives of critically ill patients explored by diaries study (The "INSPIRED" study)

BACKGROUND

There is rising prevalence of post-traumatic-stress-disorder (PTSD) in patients and their relatives after ICU discharge. The impact of ICU diaries on PTSD in relatives of critically ill patients in Australia has not been fully evaluated.

OBJECTIVES

To determine if relatives of an Australian critically ill population were interested in using ICU diaries. To determine the prevalence and impact of ICU diaries upon symptoms of PTSD, depression and anxiety in relatives of an Australian critically ill population.

METHODS DESIGN

Prospective, observational, exploratory study.

SETTING

Royal Adelaide Hospital (RAH), Adelaide, Australia.

PARTICIPANTS

One hundred and eight consecutive patients, staying >48h in a level 3 ICU were identified. A survey using DASS-21, IES-R questionnaires was performed on admission followed by a repeat survey 90days post discharge from ICU. An IES-R score >33 was used to define severe PTSD symptoms. A comparison between subjects who did and did not complete their diaries was performed.

RESULTS

Forty subjects refused to participate, eight were excluded, and sixty family members were included for analysis, thirty-six of whom completed diaries. There was no statistically significant difference between PTSD symptom scores at follow-up controlling for useful diary completion (complete - see methods) and PTSD at baseline. There was a statistically significant association between PTSD and unemployment, controlling for PTSD at baseline (P value=0.0045). Family members had significantly higher odds of PTSD at baseline compared to 3 month follow up (P value=0.0092, Odds Ratio=3.3, 95% CI: 1.3, 8.2). This was independent of the completeness of the diaries and adjusted for clustering on subject. Family members with incomplete diaries were less likely to report depressive symptoms at baseline (P value=0.0218, estimate=-4.6, 95% CI: -8.5, -0.7). Diary completion was not indicative of the likelihood of family members to report PTSD symptoms (P value=0.5468, estimate=-1.6, 95% CI: -6.8, 3.6).

CONCLUSION

ICU diaries were often not completed and completion did not appear to be related to the incidence of stress, anxiety, depression and PTSD symptoms in the families of patients in the ICU. This may be because Australian families are generally not interested in maintaining a diary.

The rapid and accurate categorisation of critically ill patients (RACE) to identify outcomes of interest for longitudinal studies: a feasibility study

The capacity to measure the impact of an intervention on long-term functional outcomes might be improved if research methodology reflected our clinical approach, which is to individualise goals of care to what is achievable for each patient. The objective of this multicentre inception cohort study was to evaluate the feasibility of rapidly and accurately categorising patients, who were eligible for simulated enrolment into a clinical trial, into unique categories based on premorbid function. Once a patient met eligibility criteria a rapid 'baseline assessment' was conducted to categorise patients into one of eight specified groups. A subsequent 'gold standard' assessment was made by an independent blinded assessor once patients had recovered sufficiently to allow such an assessment to occur. Accuracy was predefined as agreement in >80% of assessments. One hundred and twenty-two patients received a baseline assessment and 104 (85%) were categorised to a unique category. One hundred and six patients survived to have a gold standard assessment performed, with 100 (94%) assigned to a unique category. Ninety-two patients had both a baseline and gold standard assessment, and these agreed in 65 (71%) patients. It was not feasible to rapidly and accurately categorise patients according to premorbid function.

Real-time kinetic binding studies at attomolar concentrations in solution phase using a single-stage opto-biosensing platform based upon infrared surface plasmons

Here we present a new generic opto-bio-sensing platform combining immobilised aptamers on an infrared plasmonic sensing device generated by nano-structured thin film that demonstrates amongst the highest index spectral sensitivities of any optical fibre sensor yielding on average 3.4 × 10⁴ nm/RIU in the aqueous index regime (with a figure of merit of 330) This offers a single stage, solution phase, atto-molar detection capability, whilst delivering real-time data for kinetic studies in water-based chemistry. The sensing platform is based upon optical fibre and has the potential to be multiplexed and used in remote sensing applications. As an example of the highly versatile capabilities of aptamer based detection using our platform, purified thrombin is detected down to 50 attomolar concentration using a volume of 1mm³ of solution without the use of any form of enhancement technique. Moreover, the device can detect nanomolar levels of thrombin in a flow cell, in the presence of 4.5% w/v albumin solution. These results are important, covering all concentrations in the human thrombin generation curve, including the problematic initial phase. Finally, selectivity is confirmed using complementary and non-complementary DNA sequences that yield performances similar to those obtained with thrombin.

The relationship between fasting plasma citrulline concentration and small intestinal function in the critically ill

Introduction

In this study, we aimed to evaluate whether fasting plasma citrulline concentration predicts subsequent glucose absorption in critically ill patients.

Methods

In a prospective observational study involving 15 healthy and 20 critically ill subjects, fasting plasma citrulline concentrations were assayed in blood samples immediately prior to the administration of a liquid test meal (1 kcal/ml; containing 3 g of 3-O-methylglucose (3-OMG)) that was infused directly into the small intestine. Serum 3-OMG concentrations were measured over the following 4 hours, with the area under the 3-OMG concentration curve (AUC) calculated as an index of glucose absorption.

Results

The groups were well matched in terms of age, sex and body mass index (BMI) (healthy subjects versus patients, mean (range) values: age, 47 (18 to 88) versus 49 (21 to 77) years; sex ratio, 60% versus 80% male; BMI, 25.2 (18.8 to 30.0) versus 25.5 (19.4 to 32.2) kg/m²). Compared to the healthy subjects, patients who were critically ill had reduced fasting citrulline concentration (26.5 (13.9 to 43.0) versus 15.2 (5.7 to 28.6) μmol/L; P < 0.01) and glucose absorption (3-OMG AUC, 79.7 (28.6 to 117.8) versus 61.0 (4.5 to 97.1) mmol/L/240 min; P = 0.05). There was no relationship between fasting citrulline concentration and subsequent glucose absorption (r = 0.28; P = 0.12).

Conclusions

Whereas both plasma citrulline concentrations and glucose absorption were reduced in critical illness, fasting plasma citrulline concentrations were not predictive of subsequent glucose absorption. These data suggest that fasting citrulline concentration does not appear to be a marker of small intestinal absorptive function in patients who are critically ill.

Coupling of magnetic and ferroelectric hysteresis by a multicomponent magnetic structure in Mn2GeO4

The olivine compound Mn(2)GeO(4) is shown to feature both a ferroelectric polarization and a ferromagnetic magnetization that are directly coupled and point along the same direction. We show that a spin spiral generates ferroelectricity, and a canted commensurate order leads to weak ferromagnetism. Symmetry suggests that the direct coupling between the ferromagnetism and ferroelectricity is mediated by Dzyaloshinskii-Moriya interactions that exist only in the ferroelectric phase, controlling both the sense of the spiral rotation and the canting of the commensurate structure. Our study demonstrates how multicomponent magnetic structures found in magnetically frustrated materials like Mn(2)GeO(4) provide a new route towards functional materials that exhibit coupled ferromagnetism and ferroelectricity.

The magnetic structure of multiferroic BaMnF4

The multiferroic material BaMnF(4) has been investigated with unpolarized and polarized neutron diffraction. The structure has been shown to be antiferromagnetic. The magnetic moments are aligned at 12° to the b direction in the bc plane, 3° different from the previously determined value. The ferromagnetic component that is indicative of the linear magnetoelectric effect was not observed.

Effects of styrene and its metabolites on different lung compartments of the mouse—cell proliferation and histomorphology

Styrene is not carcinogenic in rats but has caused pneumotoxicity and increased lung tumors after inhalation in mice. This study investigated whether styrene-7,8-oxide, ring-oxidized, and side-chain hydroxylated styrene metabolites induce cell proliferation, apoptosis, pathological changes, and glutathione depletion in mice lungs. Intraperitoneal treatment with phenylacetaldehyde and phenylacetic acid (3 x 100 mg/kg b.w./day) increased the levels of apoptosis and cell proliferation in the alveoli without producing any effects in the terminal bronchioli, the target site of tumor formation in mice. Only styrene-oxide (SO) at 3 x 100 mg/kg b.w./day and 4-vinyl-phenol (4-VP) at 3 x 35 and 3 x 20 mg/kg b.w./day, respectively, caused up to 19-fold increases in cell proliferation in the large/medium bronchi and terminal bronchioles; marginal increases in alveolar cell proliferation were noted with SO (1.6-fold) but not with 4-VP. These compounds also caused glutathione depletion in the bronchiolar epithelium and histomorphological changes of the bronchiolar epithelium in large and medium bronchi and terminal bronchioles. Changes were characterized by flattened cells and a loss of the typical bulging of the "dome-shaped" Clara cells, suggesting that Clara cells were primary target cells. The specific reactions of mouse lung to SO and 4-VP could serve as a verifiable hypothesis for the different response of rats and mice with regard to tumor formation.

OECD test strategies and methods for endocrine disruptors

The question whether (man-made or natural) chemical substances may have an adverse effect on the endocrine system has gained high visibility in the public as well as in the scientific community. This relates to possible effects on the environment as well as on human health for chemicals with (anti)estrogenic, (anti)androgenic or (anti)thyroid activity. Taking into account the broad universe of chemicals to which humans or the environment may be exposed, a sound testing strategy and robust test methods are urgently needed. Both subjects have been addressed by a specific OECD working group (EDTA-Endocrine Disruptor Testing and Assessment Task Force) involving regulatory agencies, the scientific community, chemical industry and NGOs. Like other organizations the OECD has adopted a tiered-testing strategy with the first tier using screening assays as quick and inexpensive tools, providing a way of generating alerts to potential endocrine activity that can be used to prioritize substances for definitive tests that then can determine the toxicological consequences of endocrine toxicity. The efforts of the OECD have therefore concentrated on the validation of specific screening and testing guidelines, like the uterotrophic, the Hershberger, and the "enhanced TG 407" test. The experimental testing necessary for this validation procedure is completed for the uterotrophic and the "enhanced TG 407" tests and near completion for the Hershberger assay. The data obtained so far have been published (for the uterotrophic assay) or will be submitted to the EDTA working group for final evaluation. Overall, the validation program has been very successful and should be sufficient for setting up OECD test guidelines for these experimental procedures. This will add substantially to the "tool-box" of OECD test methods that is available internationally to regulatory agencies and chemical industry for the identification and assessment of possible endocrine disruptors. Despite this success it is well recognized that the methodological "tool-box" should be supplemented by further screening and testing procedures related to effects on human health and the environment.

Review of the toxicology, human exposure and safety assessment for bisphenol A diglycidylether (BADGE)

BADGE (whose chemical names are bisphenol A diglycidylether and 2,2-bis(4-(2,3-epoxypropyl)phenyl)propane) is the lowest molecular weight oligomer in commercial epoxy resins and the major component in commercial liquid epoxy resins. The major application areas for epoxy resins are protective coatings and civil engineering. Additional applications include printed circuit boards, composites, adhesives and tooling, while a relatively small amount of epoxy resins (< 10%) finds use in protective coatings inside food and drink cans. The use of BADGE in food-contact applications was first regulated through EC Directive 2002/16/EC and amended in EC Directive 2004/13/EC with migration levels in food-contact applications being generally well below the regulatory thresholds. The paper discusses the commercial use of BADGE focusing on the current knowledge of human exposure from canned food applications. To assess the safety of this application, the exposure data are compared with no adverse effect levels (NOAEL) from various toxicological investigations with BADGE including reproductive and developmental assays, endocrine toxicity investigations, and sub-chronic and chronic assays. Consumer exposure to BADGE is almost exclusively from migration of BADGE from can coatings into food. Using a worst-case scenario that assumes BADGE migrates at the same level into all types of food, the estimated per capita daily intake for a 60-kg individual is approximately 0.16 microg kg(-1) body weight day(-1). A review of one- and two-generation reproduction studies and developmental investigations found no evidence of reproductive or endocrine toxicity, the upper ranges of dosing being determined by maternal toxicity. The lack of endocrine toxicity in the reproductive and developmental toxicological tests is supported by negative results from both in vivo and in vitro assays designed specifically to detect oestrogenic and androgenic properties of BADGE. An examination of data from sub-chronic and chronic toxicological studies support a NOAEL of 50 mg kg(-1) body weight day(-1) from the 90-day study, and a NOAEL of 15 mg kg(-1) body weight day(-1) (male rats) from the 2-year carcinogenicity study. Both NOAELS are considered appropriate for risk assessment. Comparing the estimated daily human intake of 0.16 microg kg(-1) body weight day(-1) with the NOAELS of 50 and 15 mg kg(-1) body weight day(-1) shows human exposure to BADGE from can coatings is between 250,000 and 100,000-fold lower than the NOAELs from the most sensitive toxicology tests. These large margins of safety together with lack of reproductive, developmental, endocrine and carcinogenic effects supports the continued use of BADGE for use in articles intended to come into contact with foodstuffs.

The CYP88A cytochrome P450, ent-kaurenoic acid oxidase, catalyzes three steps of the gibberellin biosynthesis pathway

We have shown that ent-kaurenoic acid oxidase, a member of the CYP88A subfamily of cytochrome P450 enzymes, catalyzes the three steps of the gibberellin biosynthetic pathway from ent-kaurenoic acid to GA(12). A gibberellin-responsive barley mutant, grd5, accumulates ent-kaurenoic acid in developing grains. Three independent grd5 mutants contain mutations in a gene encoding a member of the CYP88A subfamily of cytochrome P450 enzymes, defined by the maize Dwarf3 protein. Mutation of the Dwarf3 gene gives rise to a gibberellin-responsive dwarf phenotype, but the lesion in the gibberellin biosynthesis pathway has not been identified. Arabidopsis thaliana has two CYP88A genes, both of which are expressed. Yeast strains expressing cDNAs encoding each of the two Arabidopsis and the barley CYP88A enzymes catalyze the three steps of the GA biosynthesis pathway from ent-kaurenoic acid to GA(12). Sequence comparison suggests that the maize Dwarf3 locus also encodes ent-kaurenoic acid oxidase.

Confounded cytosine! Tinkering and the evolution of DNA

Early in the history of DNA, thymine replaced uracil, thus solving a short-term problem for storing genetic information--mutation of cytosine to uracil through deamination. Any engineer would have replaced cytosine, but evolution is a tinkerer not an engineer. By keeping cytosine and replacing uracil the problem was never eliminated, returning once again with the advent of DNA methylation.

Sentinel surveillance as an alternative approach for monitoring antibiotic-resistant invasive pneumococcal disease in Washington State

OBJECTIVES

As an alternative to statewide, mandated surveillance for antibiotic-resistant Streptococcus pneumoniae, a sentinel surveillance network of 27 hospitals was developed in Washington State.

METHODS

The utility of targeted surveillance in population centers was assessed, current laboratory susceptibility testing practices were evaluated, and a baseline of pneumococcal resistance in Washington State was obtained for use in a statewide campaign promoting the judicious use of antibiotics.

RESULTS

Between July 1997 and June 1998, 300 cases were reported; 67 (22%) had diminished susceptibility to penicillin. Only 191 (64%) were fully tested with penicillin and an extended-spectrum cephalosporin (ESC) as nationally recommended; 10.5% were resistant to penicillin and 6.8% were resistant to an ESC. The number of isolates inadequately tested declined through the year. The findings were similar to those from more comprehensive active surveillance in Oregon for the same time period.

CONCLUSIONS

Targeted surveillance may be an adequate alternative for limited monitoring of antibiotic resistance for states that choose not to mandate reporting.

Management and outcomes in a low-volume cerebral aneurysm practice

OBJECTIVE

To review management strategies, outcomes, and complications in cerebral aneurysm surgery in a low-volume aneurysm practice.

METHODS

Seventy-nine craniotomies to treat aneurysms were performed between June 1996 and November 1999. Patient management strategy is outlined, complications are assessed, and outcomes are described.

RESULTS

Twenty-six patients underwent surgery to treat unruptured aneurysms. Forty-two patients presented with Hunt and Hess Grade 1 to 3 subarachnoid hemorrhage. Eleven patients presented with Grade 4 or 5 subarachnoid hemorrhage. Twenty-four patients (92.3%) with unruptured aneurysms experienced favorable outcomes. Of the patients with unruptured anterior circulation aneurysms, 96% achieved favorable recoveries. Thirty-eight patients (90.5%) with Grade 1 to 3 subarachnoid hemorrhage experienced favorable outcomes; four of these patients were moderately disabled. Among patients with Grade 1 to 3 subarachnoid hemorrhage, the mortality rate was 7.1%. Of patients with Grade 4 or 5 subarachnoid hemorrhage, five (45.5%) experienced favorable outcomes, but four of these patients were moderately disabled; two patients (18.2%) were severely disabled, and four patients (36.4%) died.

CONCLUSION

Acceptable clinical outcomes can be achieved in lower-volume aneurysm practices. A multidisciplinary subspecialty approach with aggressive perioperative care, especially in the prevention and treatment of cerebral vasospasm, is important in obtaining these results. Close interaction with medical consultants and other subspecialists is necessary.

Evidence of a role for SHP-1 in platelet activation by the collagen receptor glycoprotein VI

The Src homology (SH)2 domain-containing protein-tyrosine phosphatase SHP-1 is tyrosine phosphorylated in platelets in response to the glycoprotein VI (GPVI)-selective agonist collagen-related peptide (CRP), collagen, and thrombin. Two major unidentified tyrosine-phosphorylated bands of 28 and 32 kDa and a minor band of 130 kDa coprecipitate with SHP-1 in response to all three agonists. Additionally, tyrosine-phosphorylated proteins of 50-55 and 70 kDa specifically associate with SHP-1 following stimulation by CRP and collagen. The tyrosine kinases Lyn, which exists as a 53 and 56-kDa doublet, and Syk were identified as major components of these bands, respectively. Kinase assays on SHP-1 immunoprecipitates performed in the presence of the Src family kinase inhibitor PP1 confirmed the presence of a Src kinase in CRP- but not thrombin-stimulated cells. Lyn, Syk, and SLP-76, along with tyrosine-phosphorylated 28-, 32-, and 130-kDa proteins, bound selectively to a glutathione S-transferase protein encoding the SH2 domains of SHP-1, suggesting that this is the major site of interaction. Platelets isolated from motheaten viable mice (mev/mev) revealed the presence of a heavily tyrosine-phosphorylated 26-kDa protein that was not found in wild-type platelets. CRP-stimulated mev/mev platelets manifested hypophosphorylation of Syk and Lyn and reduced P-selectin expression relative to controls. These observations provide evidence of a functional role for SHP-1 in platelet activation by GPVI.

Role of pericytes in vascular calcification: a review

Pericytes are defined by their location in vivo; the pericyte partially surrounds the endothelial cell of the microvessel and shares a common basement membrane with it. As an integral part of the microvasculature, pericytes play a fundamental role in maintaining local and tissue homeostasis. Current evidence also suggests that pericytes function as progenitor cells capable of differentiating into a variety of different cell types including osteoblasts, chondrocytes and adipocytes. It is now apparent that cells resembling microvascular pericytes, and termed 'pericyte-like' cells, have a widespread distribution in vivo. Pericyte-like cells have been identified in the inner intima, the outer media, and in the vasa vasora of the adventitia of large, medium and small human arteries (1, 2). Moreover, recent studies have suggested that these cells may be responsible, at least in part, for mediating the calcification commonly associated with atherosclerosis (1, 3, 4). In this review, we a) examine the evidence that microvascular pericytes deposit a bone-like mineralised matrix in vitro, b) compare the morphological and biochemical properties of microvascular pericytes, calcifying vascular cells (CVCs) and 'classical' smooth muscle cells (SMCs) isolated from bovine aorta, c) demonstrate that microvascular pericytes deposit a well-organised matrix of bone, cartilage and fibrous tissue in vivo, and d) discuss recent studies designed to gain a better understanding of how pericyte differentiation is regulated.

Differential sugar absorption as a marker for adaptation in short bowel syndrome

PURPOSE

There are no reliable monitoring methods for following up with patients with short bowel syndrome (SBS). This study examines the use of inert sugar markers (mannitol and lactulose) as indicators of the surface area increases occurring with adaptation.

METHODS

Juvenile male rats underwent either transection with intestinal reanastomosis or resection with removal of the proximal 90% of the small bowel, leaving 10 cm of terminal ileum (n = 8 in each group). Animals were studied in vivo, measuring absorption of mannitol and lactulose on day 7, 14, and 28 and killed with the representative histological samples taken on day 7, 14, and 28.

RESULTS

Resected animals showed significant increases in intestinal length (initial bowel length 10 cm, final length 17.8 +/- 1.4 cm, while transected showed no significant changes (101 +/- 2 cm): resection also increased intestinal circumference (initial circumference 0.5 cm +/- 0.1 cm, final circumference 1.1 cm +/- 0.2 cm in resected animals, while transected animals remained unchanged). Resected animals also showed significant increases in villus height (0.7 +/- 0.06 mm initially, 0.9 +/- 0.09 mm at day 28), and but a decrease in villus density (116 +/- 20 villi/mm2 initially, 78 +/- 20 villi/mm2 at day 28), again controls showed no changes. This resulted in a significant increase in intestinal surface area in resected animals over the study; surface area initially calculated at 640 +/- 80 cm2 increasing to 1,440 +/- 360 cm2, while controls showed no significant change in surface area. There was also an increase in mannitol absorption, which went from 1.8 +/- 0.6% on day 7 to 2.56 +/- 0.6% on day 28 in resected animals, while permeability actually decreased over time. (All data mean +/- SD, with P<.05 by Student's t test). Mannitol absorption correlated well with intestinal surface area (R2 = 0.82).

CONCLUSION

These results suggest that inert sugar markers, such as lactulose and mannitol, may be useful in following adaptation in patients who have short bowel syndrome.

The nature of the last universal common ancestor

Cytologically, prokaryotes appear simpler and thus evolutionarily 'older' than eukaryotes. In terms of RNA processing, however, prokaryotes are sophisticated and eukaryotes, which retain many features of an RNA-world, appear primitive. The last universal common ancestor may have been mesophilic and could have had many features of the eukaryote genome, but its cytology is unknown.

Early evolution: prokaryotes, the new kids on the block

Prokaryotes are generally assumed to be the oldest existing form of life on earth. This assumption, however, makes it difficult to understand certain aspects of the transition from earlier stages in the origin of life to more complex ones, and it does not account for many apparently ancient features in the eukaryotes. From a model of the RNA world, based on relic RNA species in modern organisms, one can infer that there was an absolute requirement for a high-accuracy RNA replicase even before proteins evolved. In addition, we argue here that the ribosome (together with the RNAs involved in its assembly) is so large that it must have had a prior function before protein synthesis. A model that connects and equates these two requirements (high-accuracy RNA replicase and prior function of the ribosome) can explain many steps in the origin of life while accounting for the observation that eukaryotes have retained more vestiges of the RNA world. The later derivation of prokaryote RNA metabolism and genome structure can be accounted for by the two complementary mechanisms of r-selection and thermoreduction.

Arabidopsis ent-kaurene oxidase catalyzes three steps of gibberellin biosynthesis

The Arabidopsis GA3 cDNA was expressed in yeast (Saccharomyces cerevisiae) and the ability of the transformed yeast cells to metabolize ent-kaurene was tested. We show by full-scan gas chromatography-mass spectrometry that the transformed cells produce ent-kaurenoic acid, and demonstrate that the single enzyme GA3 (ent-kaurene oxidase) catalyzes the three steps of gibberellin biosynthesis from ent-kaurene to ent-kaurenoic acid.

Recurrent benign parotid tumours: the lesson not learnt yet?

BACKGROUND

To study the behaviour of recurrent benign parotid tumours, recurrence characteristics and problems faced with the removal of these lesions.

METHODS

We reviewed the charts of the work of a single surgeon between 1971 and 1996.

RESULTS

There were 24 patients (13 women, 11 men) with a mean age of 44 years at re-operation. Mean follow-up period was 10 years (range 1-22 years). There were 21 recurrent pleomorphic adenomas, two monomorphic adenomas and one patient with recurrent oncocytoma. Nine patients had solitary recurrence with a mean size of 14 mm, 15 patients had multiple recurrences with a mean size of 8 mm. There was malignant transformation of a previously benign lump in one patient. Three patients presented with a second or third recurrence. Overall facial nerve paralysis was 53% (38% temporary and 15% permanent). Frey's syndrome occurred in four patients (17%).

CONCLUSIONS

Recurrent benign parotid tumours are uncommon if superficial parotidectomy (SP) is the performed initially; recurrence rates are between 0-4%. The recurrences are usually slow growing and require lengthy follow-up. Pre-operative diagnosis of a lump in the region of previous excision is useful in treatment planning. Malignant transformation in previous benign lump should be considered and fine needle aspiration biopsy may help in diagnosis. Facial nerve injury is more likely if the tumour is deep, in multiple sites or involves extensive scar tissue. Radiotherapy is controversial, it should be considered if there has been tumour spillage following re-operation.

Evaluation of plasmid DNA for in vivo gene therapy: factors affecting the number of transfected fibers

Gene transfer by intramuscular injection of plasmid DNA has potential application in gene therapy. We examined factors affecting the number of expressing fibers, in contrast to total expression, following injection of plasmid DNA. Barium chloride proved effective in inducing muscle necrosis and regeneration in mice, and this increased the number of fibers expressing a reporter gene. Coinjection of ion-channel modulators did not increase the number of positive fibers, but increasing dose and repeated administration of plasmid did. Importantly, the plasmid size (7-16 kb) did not affect the number of fibers expressing the transgene, in both normal and regenerating muscle.

The Fc receptor gamma-chain and the tyrosine kinase Syk are essential for activation of mouse platelets by collagen

Activation of mouse platelets by collagen is associated with tyrosine phosphorylation of multiple proteins including the Fc receptor gamma-chain, the tyrosine kinase Syk and phospholipase Cgamma2, suggesting that collagen signals in a manner similar to that of immune receptors. This hypothesis has been tested using platelets from mice lacking the Fc receptor gamma-chain or Syk. Tyrosine phosphorylation of Syk and phospholipase Cgamma2 by collagen stimulation is absent in mice lacking the Fc receptor gamma-chain. Tyrosine phosphorylation of phospholipase Cgamma2 by collagen stimulation is also absent in mice platelets which lack Syk, although phosphorylation of the Fc receptor gamma-chain is maintained. In contrast, tyrosine phosphorylation of platelet proteins by the G protein-coupled receptor agonist thrombin is maintained in mouse platelets deficient in Fc receptor gamma-chain or Syk. The absence of Fc receptor gamma-chain or Syk is accompanied by a loss of secretion and aggregation responses in collagen- but not thrombin-stimulated platelets. These observations provide the first direct evidence of an essential role for the immunoreceptor tyrosine-based activation motif (ITAM) in signalling by a non-immune receptor stimulus.

Grain Development Mutants of Barley ([alpha]-Amylase Production during Grain Maturation and Its Relation to Endogenous Gibberellic Acid Content)

Barley (Hordeum vulgare L. Himalaya) mutants with altered grain morphology were isolated to investigate whether defects in grain development, possibly involving gibberellins (GAs) and abscisic acid, would lead to altered patterns of [alpha]-amylase gene expression. Following treatment with sodium azide, 75 mutants, typically showing grain shriveling, were identified. At grain maturity 15 of the 75 mutants had higher [alpha]-amylase activities in shriveled grains compared with either phenotypically normal grains that developed on the same heterozygous plant or with grains of cv Himalaya. Studies of four of these mutants demonstrated increased levels of both high- and low-isoelectric point [alpha]-amylase isozymes midway through grain development. This category of mutant has been designated pga, for premature grain [alpha]-amylase. One such mutant (M326) showed an endosperm-determined inheritance pattern. When crossed into a (GA-deficient) dwarfing background there was a 10- to 20-fold reduction in [alpha]-amylase activity, suggesting a requirement for GA biosynthesis. Endogenous GAs and abscisic acid were quantified by combined gas chromatography-specific ion monitoring in normal and mutant grains of heterozygous M326 plants during the period of [alpha]-amylase accumulation. Mutant grains had significantly higher (5.8-fold) levels of the bioactive GA1 compared with normal grains but much lower (approximately 10-fold) levels of the 2[beta]-hydroxylated ("inactive") GAs, typical of developing barley grains (e.g. GA8, GA34, GA48). We propose that a reduced extent of 2[beta]-hydroxylation in the mutant grains results in an increased level of GA1, which is responsible for premature [alpha]-amylase gene expression.

Immune responses, not promoter inactivation, are responsible for decreased long-term expression following plasmid gene transfer into skeletal muscle

Long-term high-level in vivo gene expression appears to depend on the promoter chosen to drive the gene of choice. In many cases the promoter appears to 'switch off' some time after in vivo gene transfer. We demonstrate that, following intramuscular injection of beta-galactosidase reporter plasmids, promoter 'switch off' is due to elimination of fibres expressing the transferred reporter gene by activation of a Th1 (cytotoxic) immune response. This finding, in the absence of stimulation of the immune system by viral vector proteins, has implications not only for gene transfer experiments but for the future of muscle-directed gene therapy.

Syk interacts with tyrosine-phosphorylated proteins in human platelets activated by collagen and cross-linking of the Fc gamma-IIA receptor

Activation of human platelets by cross-linking of the platelet low-affinity IgG receptor, the Fc gamma receptor IIA (Fc gamma-RIIA), or by collagen is associated with rapid phosphorylation on tyrosine of the non-receptor tyrosine kinase syk. Phosphorylation is still observed, albeit sometimes reduced, in the presence of a combination of a protein kinase C inhibitor, Ro 31-8220, and the intracellular calcium chelator, BAPTA-AM, demonstrating independence from phosphoinositide-specific phospholipase C (PLC) activity. In contrast, the combination of Ro 31-8220 and BAPTA-AM completely inhibits phosphorylation of syk in thrombin-stimulated platelets. Phosphorylation of syk increases its autophosphorylation activity measured in a kinase assay performed on syk immunoprecipitates. Fc gamma-RIIA also undergoes phosphorylation in syk immunoprecipitates from platelets activated by cross-linking of Fc gamma-RIIA but not by collagen, suggesting that it associates with the kinase. Consistent with this, tyrosine-phosphorylated Fc gamma-RIIA is precipitated by a glutathione S-transferase (GST) fusion protein containing the tandem src homology (SH2) domains of syk from Fc gamma-RIIA- but not collagen-activated cells. Two uncharacterized tyrosine-phosphorylated proteins of 40 and 65 kDa are uniquely precipitated by a GST fusion protein containing the tandem syk-SH2 domains in collagen-stimulated platelets. A peptide based on the antigen recognition activation motif (ARAM) of Fc gamma-RIIA, and phosphorylated on the two tyrosine residues found within this region, selectively binds syk from lysates of resting platelets; this interaction is not seen with a non-phosphorylated peptide. Kinase assays on Fc gamma-RIIA immunoprecipitates reveal the constitutive association of an unidentified kinase activity in resting cells which phosphorylates a 67 kDa protein. Syk is not detected in Fc gamma-RIIA immunoprecipitates from resting cells but associates with the receptor following activation and, together with Fc gamma-RIIA, is phosphorylated in the kinase assay in vitro. These results demonstrate that syk is activated by Fc gamma-RIIA cross-linking and collagen, independent of PLC, suggesting that it may have an important role in the early events associated with platelet activation. The association of syk with Fc gamma-RIIA appears to be mediated through the tandem SH2 domains in syk and the ARAM motif of Fc gamma-RIIA. A similar interaction may underlie the response to collagen, suggesting that its signalling receptor contains an ARAM motif.

Preliminary findings of ophthalmological abnormalities in farmed halibut

Ocular abnormalities occurring in farmed halibut at the Sea Fish Industry Authority Marine Farming Unit, Ardtoe, Argyll were investigated clinically and post mortem. A significant number of fish were found to have posterior polar cystic changes either causing scleral ectasia or gross degenerative posterior segment abnormalities with chorioretinal atrophy. Other ocular abnormalities included cataract formation and intraocular inflammation. In a small number of fish gas bubble formation in the anterior chamber was observed during capture and examination. It is possible that the lesions seen in these fish are a form of gas bubble disease although super-saturation, the cause of gas bubble disease previously reported in farmed fish, does not occur in the tanks in which these fish are housed. While this paper provides no answers with regard to the aetiopathogenesis of the lesions, it is hoped that it will stimulate discussion, leading to resolution of these questions through a multidisciplinary approach to the problem.

Ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) and the tyrphostin ST271 inhibit phospholipase C in human platelets by preventing Ca2+ entry

In the present study, the roles of Ca2+ and fibrinogen receptor occupancy in the regulation of phospholipase C by G protein-coupled and tyrosine kinase-linked receptor pathways in human platelets have been investigated. Agonist stimulation of phospholipase C was not altered significantly in the absence of stirring or in the presence of the fibrinogen receptor antagonist arginine-glycine-aspartate-serine, conditions that prevent platelet aggregation. Similarly, elevation of intracellular Ca2+ levels by the ionophores A23187 or ionomycin did not induce formation of inositol phosphates. In contrast, chelation of extracellular Ca2+ by ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) reduced formation of inositol phosphates by G protein receptor (thrombin)- and tyrosine kinase (Fc receptor and peroxovanadate)-regulated pathways. Similarly, short term exposure to Ni2+ ions, which also prevent Ca2+ entry, inhibited thrombin-stimulated formation of inositol phosphates. Loading of platelets with the intracellular Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) markedly suppressed elevation of intracellular Ca2+ and formation of inositol phosphates in platelets stimulated by G protein receptor- and tyrosine kinase-regulated pathways. The greater inhibition of phospholipase C by BAPTA, relative to that induced by EGTA, is consistent with the more pronounced inhibition of intracellular Ca2+ elevation. The tyrphostin tyrosine kinase inhibitor ST271 also reduced intracellular Ca2+ levels and inhibited activation of phospholipase C. The degree of inhibition of phospholipase C by ST271 was slightly greater than that induced by EGTA but was not additive with the effect of EGTA, suggesting a common mode of action. It is concluded that elevation of intracellular Ca2+ regulates agonist-induced activation of phospholipase C and that this contributes to the inhibition of thrombin-induced formation of inositol phosphates by the tyrphostin ST271.

Styrene production, use, and human exposure

Styrene is an extremely important commodity chemical used extensively in the manufacture of numerous polymers and copolymers, including polystyrene, acrylonitrile-butadiene-styrene (ABS), styrene-acrylonitrile (SAN), styrene-butadiene latex, and styrene-butadiene rubber. Styrene is a component of cigarette smoke and automobile exhaust, and it may occur naturally at low levels in various types of foods. The highest potential human exposures to styrene occur in occupational settings, particularly those involving the production of large glass-reinforced polyester products such as boats, which require manual lay-up and spray-up operations. Substantially lower occupational exposures occur in styrene monomer and polymer production facilities. The general public is exposed to very low concentrations of styrene in ambient air, indoor air, food, and drinking water.