Prognosis after neoadjuvant chemoradiation or chemotherapy for locally advanced gastro-oesophageal junctional adenocarcinoma

BACKGROUND

Trials typically group cancers of the gastro-oesophageal junction (GOJ) with oesophageal or gastric cancer when studying neoadjuvant chemoradiation and perioperative chemotherapy, so the results may not be fully applicable to GOJ cancer. Because optimal neoadjuvant treatment for GOJ cancer remains controversial, outcomes with neoadjuvant chemoradiation versus chemotherapy for locally advanced GOJ adenocarcinoma were compared retrospectively.

METHODS

Data were collected from all patients who underwent neoadjuvant treatment followed by surgery for adenocarcinoma located at the GOJ at a single high-volume institution between 2002 and 2017. Postoperative major complications and mortality were compared between groups using Fisher's exact test. Overall survival (OS) and disease-free survival (DFS) were assessed by log rank test and multivariable Cox regression analyses. Cumulative incidence functions were used to estimate recurrence, and groups were compared using Gray's test.

RESULTS

Of 775 patients, 650 had neoadjuvant chemoradiation and 125 had chemotherapy. These groups were comparable in terms of clinical tumour and lymph node categories, although the chemoradiation group had greater proportions of white men, complete pathological response to chemotherapy, and smaller proportions of diffuse cancer, poor differentiation, and neurovascular invasion. Postoperative major complications (20.0 versus 17.6 per cent) and 30-day mortality (1.7 versus 1.6 per cent) were not significantly different between the chemoradiation and chemotherapy groups. After adjustment, type of therapy (chemoradiation versus chemotherapy) was not significantly associated with OS (hazard ratio (HR) 1.26, 95 per cent c.i. 0.96 to 1.67) or DFS (HR 1.27, 0.98 to 1.64). Type of recurrence (local, regional, or distant) did not differ after neoadjuvant chemoradiation versus chemotherapy.

CONCLUSION

In patients undergoing surgical resection for locally advanced adenocarcinoma of the GOJ, OS and DFS did not differ significantly between patients who had neoadjuvant chemoradiation compared with chemotherapy.

Rational design, synthesis and testing of novel tricyclic topoisomerase inhibitors for the treatment of bacterial infections part 1

The alarming reduction in drug effectiveness against bacterial infections has created an urgent need for the development of new antibacterial agents that circumvent bacterial resistance mechanisms. We report here a series of DNA gyrase and topoisomerase IV inhibitors that demonstrate potent activity against a range of Gram-positive and selected Gram-negative organisms, including clinically-relevant and drug-resistant strains. In part 1, we present a detailed structure activity relationship (SAR) analysis that led to the discovery of our previously disclosed compound, REDX05931, which has a minimum inhibitory concentration (MIC) of 0.06 μg mL^-1 against fluoroquinolone-resistant Staphylococcus aureus. Although in vitro hERG and CYP inhibition precluded further development, it validates a rational design approach to address this urgent unmet medical need and provides a scaffold for further optimisation, which is presented in part 2.

Pathologic features of response to neoadjuvant anti-PD-1 in resected non-small-cell lung carcinoma: a proposal for quantitative immune-related pathologic response criteria (irPRC)

Background

Neoadjuvant anti-PD-1 may improve outcomes for patients with resectable NSCLC and provides a critical window for examining pathologic features associated with response. Resections showing major pathologic response to neoadjuvant therapy, defined as ≤10% residual viable tumor (RVT), may predict improved long-term patient outcome. However, %RVT calculations were developed in the context of chemotherapy (%cRVT). An immune-related %RVT (%irRVT) has yet to be developed.

Patients and methods

The first trial of neoadjuvant anti-PD-1 (nivolumab, NCT02259621) was just reported. We analyzed hematoxylin and eosin-stained slides from the post-treatment resection specimens of the 20 patients with non-small-cell lung carcinoma who underwent definitive surgery. Pretreatment tumor biopsies and preresection radiographic 'tumor' measurements were also assessed.

Results

We found that the regression bed (the area of immune-mediated tumor clearance) accounts for the previously noted discrepancy between CT imaging and pathologic assessment of residual tumor. The regression bed is characterized by (i) immune activation-dense tumor infiltrating lymphocytes with macrophages and tertiary lymphoid structures; (ii) massive tumor cell death-cholesterol clefts; and (iii) tissue repair-neovascularization and proliferative fibrosis (each feature enriched in major pathologic responders versus nonresponders, P < 0.05). This distinct constellation of histologic findings was not identified in any pretreatment specimens. Histopathologic features of the regression bed were used to develop 'Immune-Related Pathologic Response Criteria' (irPRC), and these criteria were shown to be reproducible amongst pathologists. Specifically, %irRVT had improved interobserver consistency compared with %cRVT [median per-case %RVT variability 5% (0%-29%) versus 10% (0%-58%), P = 0.007] and a twofold decrease in median standard deviation across pathologists within a sample (4.6 versus 2.2, P = 0.002).

Conclusions

irPRC may be used to standardize pathologic assessment of immunotherapeutic efficacy. Long-term follow-up is needed to determine irPRC reliability as a surrogate for recurrence-free and overall survival.

Laying hen production and welfare in enriched colony cages at different stocking densities

Many laying hen companies in the United States are pledging to move away from intensive conventional cages to extensive housing systems. Enriched colony cages (ECC) are a practical alternative to conventional cage systems. Scientific research is limited on the effects of ECC on hen production and welfare. Therefore, the objective of this study was to evaluate the effects of stocking density on welfare and performance with the overall outcome to provide guidance on stocking density for ECC. At 16 wk, W-36 pullets were placed into 2 commercial ECC housing systems. Within each ECC enclosure, hens were allocated into 1 of 6 stocking densities: A) 465 to 484 cm2/bird, B) 581 to 606 cm2/bird, C) 652 to 677 cm2/bird, D) 754 to 780 cm2/bird, E) 799 to 832 cm2/bird, and F) 923 to 955 cm2/bird. Body weight, egg production, mortality, and Welfare Quality data were collected each 28 d period from 17 to 68 wk. The 6 ECC stocking densities had several transient effects on production measures within age periods with no difference in hen-day production (P > 0.05). Body weight was affected by stocking density (P < 0.05) where hens raised at stocking density A (465 to 484 cm2/bird) weighed at least 25 g less than hens from other stocking densities. Stocking density differences for Welfare Quality assessments were only apparent for feather coverage. Hens raised at stocking density A (465 to 484 cm2) consistently had the poorest (P < 0.05) crop, keel, belly, back, and rump feather coverage. The keel, neck, and back body regions had poorer feather coverage when hens were raised at stocking densities B (581 to 606 cm2) and C (652 to 677 cm2) compared to hens from lower stocking densities (P < 0.05). Therefore, the minimum area per hen housed in commercial ECC systems should be 754 cm2 per bird for greater feather coverage.

National guidelines may reduce socioeconomic disparities in treatment selection for esophageal cancer

The 2011 National Comprehensive Cancer Network guidelines first incorporated the results of the landmark CROSS trial, establishing induction therapy (chemotherapy ± radiation) and surgery as the treatment standard for locoregional esophageal cancer in the United States. The effect of guideline publication on socioeconomic status (SES) inequalities in cancer treatment selection remains unknown. Patients diagnosed with Stage II/III esophageal cancer between 2004 and 2013 who underwent curative treatment with definitive chemoradiation or multimodality treatment (induction and surgery) were identified from the Surveillance, Epidemiology and End Results (SEER)-Medicare registry. Clinicopathologic characteristics were compared between the two therapies. Multivariable regression analysis was used to adjust for known factors associated with treatment selection. An interaction term with respect to guideline publication and SES was included Of the 2,148 patients included, 1,478 (68.8%) received definitive chemoradiation and 670 (31.2%) induction and surgery. Guideline publication was associated with a 16.1% increase in patients receiving induction and surgery in the low SES group (21.4% preguideline publication vs. 37.5% after). In comparison, a 4.5% increase occurred during the same period in the high SES status group (31.8% vs. 36.3%). After adjusting for factors associated with treatment selection, guideline publication was associated with a 78% increase in likelihood of receiving induction and surgery among lower SES patients (odds ratio 1.78; 95% confidence interval (CI): 1.05,3.03). Following the new guideline publication, patients living in low SES areas were more likely to receive optimal treatment. Increased dissemination of guidelines may lead to increased adherence to evidence-based treatment standards.

Effects of different litter substrates and induced molt on production performance and welfare quality parameters of white Leghorn hens housed in multi-tiered aviary system

More than 90% of the commercial egg production in the United States is pledged to be in cage-free systems by 2025. Management practices like induced molting and litter area management have come under scrutiny because of the housing system change. The aim of this study was to determine the welfare and production implications of different litter substrates and also evaluate induced molting of hens in a cage-free system. Bovan White hens were housed in a multi-tier aviary system with daily access to open litter area of either Astroturf (AT), wood shavings (SH), or straw (ST) and bare concrete floor (CO) serving as control. At 68 wk of age, molt was induced in half of the hens whereas the other half continued without molting to 116 wk. Production and welfare parameters were measured periodically throughout first and second cycles. Litter substrate did not influence hen-day production and case-weight measurements. However, CO had the lowest total number of eggs produced during the first cycle (P < 0.05). Hen-day percentage was approximately 14% greater in molted hens during the second cycle with egg case weight being heavier in non-molt hens toward the end of second cycle (P < 0.05). The only welfare parameter influenced by litter substrate during the first cycle was a greater crop feather loss in AT than ST at mid-lay (P < 0.05). Keel deformations increased with age irrespective of the litter substrate with 91.5% of palpated hens having keel deformations at the end of first cycle (P < 0.05). Molting did not influence the keel palpation and footpad scores whereas frequency of moderate comb wound was greater in molt hens during molt (P < 0.05). Severe feather loss was seen in non-molt hens during the second cycle (P < 0.05). Litter substrate does not affect production and physical parameters of welfare of hens in a multi-tier aviary system. Additionally, induced molting can be successfully carried out in the multi-tier cage-free system.

Urine and serum midkine levels in an Australian chronic kidney disease clinic population: an observational study

BACKGROUND AND OBJECTIVES

The cytokine midkine (MK) is pathologically implicated in progressive chronic kidney disease (CKD) and its systemic consequences and has potential as both a biomarker and therapeutic target. To date, there are no published data on MK levels in patients with different stages of CKD. This study aims to quantify MK levels in patients with CKD and to identify any correlation with CKD stage, cause, progression, comorbid disease or prescribed medication.

METHODS

In this observational, single-centre study, demographic data were collected, and serum and urine assayed from 197 patients with CKD and 19 healthy volunteers in an outpatient setting.

RESULTS

The median serum and urine MK level in volunteers was 754 pg/mL (IQR: 554-1025) and 239 pg/mL (IQR: 154-568), respectively. Compared with serum MK in stage 1 CKD (660 pg/mL, IQR: 417-893), serum MK increased in stage 3 (1878 pg/mL, IQR: 1188-2756; p<0.001), 4 (2768 pg/mL, IQR: 2065-4735; p<0.001) and 5 (4816 pg/mL, IQ: 37477807; p<0.001). Urine MK levels increased from stage 1 CKD (343 pg/mL, IQR: 147-437) to stage 3 (1007 pg/mL, IQR: 465-2766; p=0.07), 4 (2961 pg/mL, IQR: 1368-5686; p=0.005) and 5 (6722 pg/mL, IQR: 3796-10 060; p=0.001). Fractional MK excretion (FeMK) increased from stage 1 CKD (0.159, IQR: 0.145-0.299) to stage 3 (1.024, IQR: 0.451-1.886, p=0.047), 4 (3.39, IQR: 2.10-5.82, p=0.004) and 5 (11.95, IQR: 5.36-24.41, p<0.001). When adjusted for estimated glomerular filtration rate, neither serum nor urine MK correlated with primary CKD diagnosis or CKD progression (small sample). There was a positive correlation between protein:creatinine ratio and FeMK (p=0.003). Angiotensin blockade (adjusted for proteinuria) was associated with lower urine MK (p=0.018) and FeMK (p=0.025).

CONCLUSION

MK levels sequentially rise with CKD stage beyond stage 2, and our data support existing animal evidence for an MK/renin angiotensin-system/proteinuria relationship. To what extent this is related to renal clearance versus pathology, or the consequences of chronically elevated MK levels requires further exploration.

Bilateral peroneal artery aneurysms

True aneurysm of the tibial arteries is a rare clinical condition. We report the case of a 67-year-old man who presented with a gradual onset of right calf swelling and pain. Imaging revealed large aneurysms arising from the proximal peroneal arteries bilaterally, measuring 7.4cm and 4cm on the right and left respectively. A detailed medical history, clinical examination and laboratory investigations did not identify evidence of an underlying cause. A surgical reconstruction with an interposition vein graft was successfully performed. To our knowledge, this is the first reported case of primary aneurysm of the peroneal artery in the English literature. We undertook a systematic literature review to identify all reported cases of primary aneurysms of the tibial arteries. The clinical presentation, modes of investigation and interventional treatments are discussed.

Influence of commercial laying hen housing systems on the incidence and identification of Salmonella and Campylobacter

The housing of laying hens is important for social, industrial, and regulatory aspects. Many studies have compared hen housing systems on the research farm, but few have fully examined commercial housing systems and management strategies. The current study compared hens housed in commercial cage-free aviary, conventional cage, and enriched colony cage systems. Environmental and eggshell pool samples were collected from selected cages/segments of the housing systems throughout the production cycle and monitored for Salmonella and Campylobacter prevalence. At 77 wk of age, 120 hens per housing system were examined for Salmonella and Campylobacter colonization in the: adrenal glands, spleen, ceca, follicles, and upper reproductive tract. All isolates detected from environmental swabs, eggshell pools, and tissues were identified for serotype. Two predominant Salmonella were detected in all samples: S. Braenderup and S. Kentucky. Campylobacter coli and C. jejuni were the only Campylobacter detected in the flocks. Across all housing systems, approximately 7% of hens were colonized with Salmonella, whereas > 90% were colonized with Campylobacter. Salmonella Braenderup was the isolate most frequently detected in environmental swabs (P < 0.0001) and housing system impacted Salmonella spp. shedding (P < 0.0001). Campylobacter jejuni was the isolate most frequently found in environmental swabs (P < 0.01), while housing system impacted the prevalence of C. coli and jejuni in ceca (P < 0.0001). The results of this study provide a greater understanding of the impact of hen housing systems on hen health and product safety. Additionally, producers and academia can utilize the findings to make informed decisions on hen housing and management strategies to enhance hen health and food safety.

Pharmacokinetics and toxicity of the novel oral demethylating agent zebularine in laboratory and tumor bearing dogs

The purpose of this study was to determine the plasma pharmacokinetics (PK) and toxicity of zebularine, an oral cytidine analog with demethylating activity, in dogs. Plasma zebularine concentrations were determined by HPLC-MS/MS following an oral zebularine dose of 8 or 4 mg kg^-1 . Plasma zebularine clearance was constant. Mean maximum concentration (C_max ) was 23 ± 4.8 and 8.6 ± 1.4 µM following 8 and 4 mg kg^-1 , respectively. Mean half-life was 5.7 ± 0.84 and 7.1 ± 2.1 following 8 and 4 mg kg^-1 , respectively. A single 8 mg kg^-1 dose was well tolerated. Daily 4 mg kg^-1 treatment in three laboratory dogs resulted in grade 4 neutropenia (n = 3), grade 1 anorexia (n = 2) and grade 1 or 2 dermatologic changes (n = 2). All adverse events resolved with supportive care. A 4 mg kg^-1 dose every 21 days was well tolerated. A follow-up dose escalation study is in progress with a lower starting dose.

Preclinical and clinical development of an anti-kappa free light chain mAb for multiple myeloma

Monoclonal antibodies (mAb) have had tremendous success in treating a variety of cancers over the past twenty years. Yet despite their widespread clinical use, which includes treatments for haematological malignancies, there are still no approved mAb therapies for multiple myeloma (MM). This is likely to change within the next few years with a number of mAb therapies being assessed in late stage clinical trials, most notably, the anti-CS-1 mAb, elotuzumab, and the anti-CD38 mAb, daratumumab, which are currently being evaluated in Phase III clinical trials for MM. In this review, we will discuss the preclinical and clinical development of MDX-1097, a Phase II candidate which targets cell membrane-associated kappa immunoglobulin free light chains expressed on the surface of MM cells.

MDX-1097 induces antibody-dependent cellular cytotoxicity against kappa multiple myeloma cells and its activity is augmented by lenalidomide

MDX-1097 is an antibody specific for a unique B cell antigen called kappa myeloma antigen (KMA) that consists of cell membrane-associated free kappa light chain (κFLC). KMA was detected on kappa human multiple myeloma cell lines (κHMCLs), on plasma cells (PCs) from kappa multiple myeloma (κMM) patients and on κPC dyscrasia tissue cryosections. In primary κMM samples, KMA was present on CD38+ cells that were CD138 and CD45 positive and/or negative. MDX-1097 exhibited a higher affinity for KMA compared to κFLC and the latter did not abrogate binding to KMA. MDX-1097-mediated antibody-dependent cellular cytotoxicity (ADCC) and in vitro exposure of target cells to the immunomodulatory drug lenalidomide resulted in increased KMA expression and ADCC. Also, in vitro exposure of peripheral blood mononuclear cells (PBMCs) to lenalidomide enhanced MDX-1097-mediated ADCC. PBMCs obtained from myeloma patients after lenalidomide therapy elicited significantly higher levels of MDX-1097-mediated ADCC than cells obtained prior to lenalidomide treatment. These data establish KMA as a relevant cell surface antigen on MM cells that can be targeted by MDX-1097. The ADCC-inducing capacity of MDX-1097 and its potentiation by lenalidomide provide a powerful rationale for clinical evaluation of MDX-1097 alone and in combination with lenalidomide.

Impact of commercial housing systems and nutrient and energy intake on laying hen performance and egg quality parameters

The US egg industry is exploring alternative housing systems for laying hens. However, limited published research related to cage-free aviary systems and enriched colony cages exists related to production, egg quality, and hen nutrition. The laying hen's nutritional requirements and resulting productivity are well established with the conventional cage system, but diminutive research is available in regards to alternative housing systems. The restrictions exist with limited availability of alternative housing systems in research settings and the considerable expense for increased bird numbers in a replicate due to alternative housing system design. Therefore, the objective of the current study was to evaluate the impact of nutrient and energy intake on production and egg quality parameters from laying hens housed at a commercial facility. Lohmann LSL laying hens were housed in three systems: enriched colony cage, cage-free aviary, and conventional cage at a single commercial facility. Daily production records were collected along with dietary changes during 15 production periods (28-d each). Eggs were analyzed for shell strength, shell thickness, Haugh unit, vitelline membrane properties, and egg solids each period. An analysis of covariance (ANCOVA) coupled with a principal components analysis (PCA) approach was utilized to assess the impact of nutritional changes on production parameters and monitored egg quality factors. The traits of hen-day production and mortality had a response only in the PCA 2 direction. This finds that as house temperature and Met intake increases, there is an inflection point at which hen-day egg production is negatively effected. Dietary changes more directly influenced shell parameters, vitelline membrane parameters, and egg total solids as opposed to laying hen housing system. Therefore, further research needs to be conducted in controlled research settings on laying hen nutrient and energy intake in the alternative housing systems and resulting impact on egg quality measures.

Measuring midkine: the utility of midkine as a biomarker in cancer and other diseases

Midkine (MK) is a pleiotropic growth factor prominently expressed during embryogenesis but down-regulated to neglible levels in healthy adults. Many published studies have demonstrated striking MK overexpression compared with healthy controls in various pathologies, including ischaemia, inflammation, autoimmunity and, most notably, in many cancers. MK expression is detectable in biopsies of diseased, but not healthy, tissues. Significantly, because it is a soluble cytokine, elevated MK is readily apparent in the blood and other body fluids such as urine and CSF, making MK a relatively convenient, accessible, non-invasive and inexpensive biomarker for population screening and early disease detection. The first diagnostic tests that quantify MK are just now receiving regulatory clearance and entering the clinic. This review examines the current state of knowledge pertaining to MK as a biomarker and highlights promising indications and clinical settings where measuring MK could make a difference to patient treatment. I also raise outstanding questions about reported variants of MK as well as MK's bio-distribution in vivo. Answering these questions in future studies will enhance our understanding of the significance of measured MK levels in both patients and healthy subjects, and may reveal further opportunities for measuring MK to diagnose disease. MK has already proven to be a biomarker that can significantly improve detection, management and treatment of cancer, and there is significant promise for developing further MK-based diagnostics in the future.

Microbiological impact of three commercial laying hen housing systems

Hen housing for commercial egg production continues to be a societal and regulatory concern. Controlled studies have examined various aspects of egg safety, but a comprehensive assessment of commercial hen housing systems in the US has not been conducted. The current study is part of a holistic, multidisciplinary comparison of the diverse aspects of commercial conventional cage, enriched colony cage, and cage-free aviary housing systems and focuses on environmental and egg microbiology. Environmental swabs and eggshell pools were collected from all housing systems during 4 production periods. Total aerobes and coliforms were enumerated, and the prevalence of Salmonella and Campylobacter spp. was determined. Environmental aerobic and coliform counts were highest for aviary drag swabs (7.5 and 4.0 log cfu/mL, respectively) and enriched colony cage scratch pad swabs (6.8 and 3.8 log cfu/mL, respectively). Aviary floor and system wire shell pools had the greatest levels of aerobic contamination for all eggshell pools (4.9 and 4.1 log cfu/mL, respectively). Hens from all housing systems were shedding Salmonella spp. (89–100% of manure belt scraper blade swabs). The dry belt litter removal processes for all housing systems appear to affect Campylobacter spp. detection (0–41% of manure belt scraper blade swabs) considering detection of Campylobacter spp. was much higher for other environmental samples. Aviary forage area drag swabs were 100% contaminated with Campylobacter spp., whereas enriched colony cage scratch pads had a 93% positive rate. There were no differences in pathogen detection in the shell pools from the 3 housing systems. Results indicate egg safety is enhanced when hens in alternative housing systems use nest boxes. Additionally, current outcomes indicate the use of scratch pads in hen housing systems needs to be more thoroughly investigated for effects on hen health and egg safety.

Site-specific water quality guidelines: 1. Derivation approaches based on physicochemical, ecotoxicological and ecological data

Generic water quality guidelines (WQGs) are developed by countries/regions as broad scale tools to assist with the protection of aquatic ecosystems from the impacts of toxicants. However, since generic WQGs cannot adequately account for the many environmental factors that may affect toxicity at a particular site, site-specific WQGs are often needed, especially for high environmental value ecosystems. The Australian and New Zealand Guidelines for Fresh and Marine Water Quality provide comprehensive guidance on methods for refining or deriving WQGs for site-specific purposes. This paper describes three such methods for deriving site-specific WQGs, namely: (1) using local reference water quality data, (2) using biological effects data from laboratory-based toxicity testing, and (3) using biological effects data from field surveys. Two case studies related to the assessment of impacts arising from mining operations in northern Australia are used to illustrate the application of these methods. Finally, the potential of several emerging methods designed to assess thresholds of ecological change from field data for deriving site-specific WQGs is discussed. Ideally, multiple lines of evidence approaches, integrating both laboratory and field data, are recommended for deriving site-specific WQGs.

Somatic CALR mutations in myeloproliferative neoplasms with nonmutated JAK2

BACKGROUND

Somatic mutations in the Janus kinase 2 gene (JAK2) occur in many myeloproliferative neoplasms, but the molecular pathogenesis of myeloproliferative neoplasms with nonmutated JAK2 is obscure, and the diagnosis of these neoplasms remains a challenge.

METHODS

We performed exome sequencing of samples obtained from 151 patients with myeloproliferative neoplasms. The mutation status of the gene encoding calreticulin (CALR) was assessed in an additional 1345 hematologic cancers, 1517 other cancers, and 550 controls. We established phylogenetic trees using hematopoietic colonies. We assessed calreticulin subcellular localization using immunofluorescence and flow cytometry.

RESULTS

Exome sequencing identified 1498 mutations in 151 patients, with medians of 6.5, 6.5, and 13.0 mutations per patient in samples of polycythemia vera, essential thrombocythemia, and myelofibrosis, respectively. Somatic CALR mutations were found in 70 to 84% of samples of myeloproliferative neoplasms with nonmutated JAK2, in 8% of myelodysplasia samples, in occasional samples of other myeloid cancers, and in none of the other cancers. A total of 148 CALR mutations were identified with 19 distinct variants. Mutations were located in exon 9 and generated a +1 base-pair frameshift, which would result in a mutant protein with a novel C-terminal. Mutant calreticulin was observed in the endoplasmic reticulum without increased cell-surface or Golgi accumulation. Patients with myeloproliferative neoplasms carrying CALR mutations presented with higher platelet counts and lower hemoglobin levels than patients with mutated JAK2. Mutation of CALR was detected in hematopoietic stem and progenitor cells. Clonal analyses showed CALR mutations in the earliest phylogenetic node, a finding consistent with its role as an initiating mutation in some patients.

CONCLUSIONS

Somatic mutations in the endoplasmic reticulum chaperone CALR were found in a majority of patients with myeloproliferative neoplasms with nonmutated JAK2. (Funded by the Kay Kendall Leukaemia Fund and others.).

Prevalence of coliforms, Salmonella, Listeria, and Campylobacter associated with eggs and the environment of conventional cage and free-range egg production

There is a desire by US consumers for eggs produced by hens in alternative production systems. As the retail shell-egg market offers these products to accommodate consumer demands, additional information is needed to ensure processing methodologies result in safe eggs from all egg sources. A study was conducted to determine if there were differences in the prevalence of coliforms, Salmonella, Listeria, and Campylobacter on and within eggs and in the environment of a sister flock of conventional cage and free-range laying hens. Microbial sampling occurred approximately every 6 wk between 20 and 79 wk of age. A random sampling of typical coliform colonies produced 371 viable isolates for biochemical identification. Twenty-nine genera or species of bacteria were identified. There was a significantly greater (P < 0.0001) prevalence of Campylobacter in the free-range nest box swabs compared with that in the free-range grass and conventional cage swab samples (number of positives: 8 nest box, 1 grass, 0 cage). Seven isolates of Listeria innocua were detected with no significant difference in prevalence between the treatments. Isolates were associated with eggshells (2 free-range floor, 1 cage) and the free-range environment (2 nest box, 2 grass). There were 21 Salmonella isolates detected between all sample locations, with no significant difference in the prevalence of Salmonella detection between the treatments. Additional studies are needed to fully understand the effect of alternative production methods on the prevalence of pathogens and coliforms associated with nest-run eggs and the production environment.

Effect of genetic selection on growth parameters and tonic immobility in Leghorn pullets

Four genetic stocks of Leghorn pullets were used to evaluate the effects of genetic selection on growth and fearfulness behavior. Three of the stocks were the Ottawa randombred control stocks from 1950 (CS5), 1959 (CS7), and 1972 (CS10). The fourth stock was a 1993 commercial laying stock (CCS) whose ancestors were involved in the formation of the randombred control stocks. Pullets were reared in a brood and grow poultry house with flat deck cages. Each stock was comprised of 840 birds with 21 replicates per strain. Body weight and feed consumption were monitored biweekly. At 16 wk of age, a 20-hen sample from each strain was analyzed for BW, body composition, and tonic immobility. There were significant (P < 0.05) differences among the stocks for BW of 1,403; 1,333; 1,332; and 1,428 g for the CS5, CS7, CS10, and CCS stocks, respectively. Furthermore, significant differences occurred with regard to feed consumption, livability, and frame size. There were no differences among the stocks in tonic immobility. Measurement of circulating corticosterone levels were shown to be significantly (P < 0.05) higher in the CCS stock (7.64 ng/mL) than for both the CS5 (4.50 ng/mL) and CS7 (4.61 ng/mL) stocks, whereas the CS10 stock was intermediate with 6.45 ng/mL. Genetic selection has affected growth parameters, although there appears to be no change in fearfulness behavior but an increase in corticosterone levels in stocks from later years.

Note: femtosecond laser micromachining of straight and linearly tapered capillary discharge waveguides

Gas-filled capillary discharge waveguides are important structures in laser-plasma interaction applications, such as the laser wakefield accelerator. We present the methodology for applying femtosecond laser micromachining in the production of capillary channels (typically 200-300 μm in diameter and 30-40 mm in length), including the formalism for capillaries with a linearly tapered diameter. The latter is demonstrated to possess a smooth variation in diameter along the length of the capillary (tunable with the micromachining trajectories). This would lead to a longitudinal plasma density gradient in the waveguide that may dramatically improve the laser-plasma interaction efficiency in applications.

Assessing the validity of the accelerometry technique for estimating the energy expenditure of diving double-crested cormorants Phalacrocorax auritus

Over the past few years, acceleration-data loggers have been used to provide calibrated proxies of energy expenditure: the accelerometry technique. Relationships between rate of oxygen consumption and a derivation of acceleration data termed "overall dynamic body acceleration" (ODBA) have now been generated for a range of species, including birds, mammals, and amphibians. In this study, we examine the utility of the accelerometry technique for estimating the energy expended by double-crested cormorants Phalacrocorax auritus to undertake a dive cycle (i.e., a dive and the subsequent pause at the surface before another dive). The results show that ODBA does not calibrate with energy expenditure in diving cormorants, where energy expenditure is calculated from measures of oxygen uptake during surface periods between dives. The possible explanations include reasons why energy expenditure may not relate to ODBA but also reasons why oxygen uptake between dives may not accurately represent energy expenditure during a dive cycle.

Phosphorylation of RelA/p65 promotes DNMT-1 recruitment to chromatin and represses transcription of the tumor metastasis suppressor gene BRMS1

The majority of patients with lung cancer present with metastatic disease. Chronic inflammation and subsequent activation of NF-κB have been associated the development of cancers. The RelA/p65 subunit of NF-κB is typically associated with transcriptional activation. In this report we show that RelA/p65 can function as an active transcriptional repressor through enhanced methylation of the BRMS1 metastasis suppressor gene promoter via direct recruitment of DNMT-1 to chromatin in response to TNF. TNF-mediated phosphorylation of S276 on RelA/p65 is required for RelA/p65-DNMT-1 interactions, chromatin loading of DNMT-1, and subsequent BRMS1 promoter methylation and transcriptional repression. The ability of RelA/65 to function as an active transcriptional repressor is promoter specific as the NF-κB-regulated gene cIAP2 is transcriptionally activated while BRMS1 is repressed under identical conditions. Small molecule inhibition of either of the minimal interacting domains between RelA/p65-DNMT-1 and RelA/p65-BRMS1 promoter abrogates BRMS1 methylation and its transcriptional repression. The ability of RelA/p65 to directly recruit DNMT-1 to chromatin resulting in promoter-specific methylation and transcriptional repression of tumor metastasis suppressor gene BRMS1 highlights a new mechanism through which NF-κB can regulate metastatic disease, and offers a potential target for newer generation epigenetic oncopharmaceuticals.

Salmonella contamination in shell eggs exposed to modified-pressure imaging for microcrack detection

Microcracks in egg shells are a food safety risk and are difficult for professional human graders to detect. Modified-pressure imaging technology with 99.6% accuracy has been developed to detect microcracks. This study was conducted to determine whether the microcrack detection system would increase penetration of Salmonella into egg contents or lead to cross-contamination within the system. Thirty dozen grade A large white retail eggs were used for each of 3 replicates. Cracked eggs were removed and 72 eggs/replicate were dip inoculated in buffered peptone water containing 10(5) cfu/mL of nalidixic acid-resistant Salmonella Typhimurium (ST), whereas 144 eggs were dipped in sterile buffered peptone water. All eggs were incubated overnight at 25°C before imaging. Forty-five eggs of each treatment were imaged in the following order: control, inoculated, control. Imaged and nonimaged eggs from each treatment were used for cultural analysis of a shell rinse, shell emulsion, and contents sample for each egg. The ST levels were monitored on brilliant green sulfa agar with 200 mg/L of nalidixic acid. Egg contents were also enriched to determine the prevalence of ST in low levels. Salmonella Typhimurium was not detected on or in any of the control eggs, including the eggs imaged after the inoculated eggs. The highest level of ST was detected in inoculated shell emulsions (4.79 log cfu/mL). No differences in ST levels were found for any sample location between imaged and nonimaged inoculated eggs. Therefore, the modified-pressure imaging system for microcrack detection did not result in microbial cross-contamination or increase the level of microbial penetration in inoculated eggs. The imaging system can be used to assess eggs for cracks without negative food safety implications.

The impact of different housing systems on egg safety and quality

A move from conventional cages to either an enriched cage or a noncage system may affect the safety or quality, or both, of the eggs laid by hens raised in this new environment. The safety of the eggs may be altered either microbiologically through contamination of internal contents with Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) or other pathogens, or both, or chemically due to contamination of internal contents with dioxins, pesticides, or heavy metals. Quality may be affected through changes in the integrity of the shell, yolk, or albumen along with changes in function, composition, or nutrition. Season, hen breed, flock age, and flock disease-vaccination status also interact to affect egg safety and quality and must be taken into account. An understanding of these different effects is prudent before any large-scale move to an alternative housing system is undertaken.

Phase I clinical trial and pharmacokinetics of intravesical mitomycin C in dogs with localized transitional cell carcinoma of the urinary bladder

BACKGROUND

Transitional cell carcinoma (TCC) is the most common cancer of the urinary tract in dogs. The most frequent cause of death is urinary obstruction from the primary tumor. Standard medical therapy for TCC is only partially effective.

HYPOTHESIS/OBJECTIVES

Intravesical administration of mitomycin C (MMC) in dogs with invasive TCC will result in antitumor activity against the primary tumor and minimal systemic drug absorption.

ANIMALS

Thirteen privately owned dogs with naturally occurring, histopathologically diagnosed TCC of the urinary bladder.

METHODS

A prospective phase I trial was performed. MMC was given intravesically (600 μg/mL initial concentration) for 1 h/d for 2 consecutive days each month. The MMC concentration was escalated to a maximum of 800 μg/mL in groups of 3 dogs until the maximum tolerated dose (MTD) was determined. Serum assays for MMC were performed to determine the extent of systemic absorption of the MMC.

RESULTS

The MTD of MMC based on local toxicoses was 700 μg/mL (1-h dwell time, 2 consecutive days). In addition, 2 dogs had severe myelosuppression and appeared to have systemic absorption of MMC. Five dogs had partial remission, and 7 dogs had stable disease.

CONCLUSIONS

Intravesical MMC has antitumor activity in dogs with invasive TCC. Further study is needed to determine the cause of the myelosuppression associated with MMC administration, and to develop strategies to minimize this risk.

Modified pressure imaging for egg crack detection and resulting egg quality

Cracks in the shell surface compromise the primary barrier for external microbial contamination of the egg. Microcracks are very small cracks in the shell surface that are difficult to detect by human graders. New technology has been developed that uses modified pressure and imaging to detect microcracks in eggs. Research has shown the system to have an accuracy of 99.6% in detecting both cracked and intact eggs. A study was undertaken to determine if quality differences existed between modified pressure imaged and control eggs during extended cold storage. Three replicates were conducted with eggs stored at 4 degrees C for 5 wk with weekly quality testing. The physical quality factors monitored were Haugh units, albumen height, egg weight, shell strength, vitelline membrane strength and elasticity, and whole egg total solids. All measurements were conducted on individual eggs (12/treatments per replicate) each week with the exception of whole egg solids, which were determined from 3 pools (4 eggs each)/treatment per replicate each week. Percentage of whole egg total solids was the only significant difference (P < 0.05) between treatments (23.65% modified pressure imaged and 23.47% control). There was a significant difference (P < 0.05) for egg weight between replicates (60.82, 58.02, and 60.58 g for replicates 1, 2, and 3, respectively). Therefore, imaging eggs in the modified pressure system for microcrack detection did not alter egg quality during extended cold storage. Utilizing the modified pressure crack detection technology would result in fewer cracked eggs reaching the consumer, consequently enhancing food safety without affecting product quality.

Physical quality and composition of retail shell eggs

There are a number of specialty shell eggs available to consumers in the US retail market. A survey consisting of white and brown large shell eggs with various production and nutritional differences (traditional, cage-free, free-roaming, pasteurized, nutritionally enhanced, and fertile) was conducted to determine if physical quality and compositional differences exist. Identical brands of eggs were purchased from the same retail outlets on 3 occasions (replicates) in a single city. The average range of time from processing to purchase for all eggs was 7.67 to 25.33 d, with traditional white eggs in retail having the shortest time. Haugh unit values ranged from 66.67 (cage-free, docosahexaenoic acid, and n-3 enhanced) to 84.42 (traditional white). Albumen height followed a similar pattern. Egg weight was greater for brown eggs (61.12 vs. 58.85 g). Brown eggs also had greater static compression shell strength than white eggs (4,130.61 vs. 3,690.31 g force). Vitelline membrane strength was greatest for traditional brown eggs (2.24 g force). Percentage of total solids and crude fat was greatest in the cage-free, n-3-enhanced white eggs (25.07 and 11.71%, respectively). Although significant differences were found between white and brown shell eggs and production methods, average values for quality attributes varied without one egg type consistently maintaining the highest or lowest values.

Airborne gamma survey of the historic Sleisbeck mine area in the Northern Territory, Australia, and its use for site rehabilitation planning

An airborne gamma-survey provided information about the extent of radioactive contamination around the historic Sleisbeck mine. Quickbird satellite data were acquired to relate airborne measurements to land cover features. Enhanced equivalent uranium (eU) levels were found to be confined to the mine and low grade waste rock dumps. The average terrestrial background radiation dose rate estimated from the airborne gamma survey data was 0.10-0.14 microGy h(-1) while the area around the mine exhibited a maximum of approximately 2.3 microGy h(-1), but measurements on the ground indicate that this maximum is exceeded in some localized areas. Rehabilitation of the site is likely to result in a threefold reduction in radiation doses to people accessing the area.

Childhood outcomes after prescription of antibiotics to pregnant women with preterm rupture of the membranes: 7-year follow-up of the ORACLE I trial

BACKGROUND

The ORACLE I trial compared the use of erythromycin and/or amoxicillin-clavulanate (co-amoxiclav) with that of placebo for women with preterm rupture of the membranes without overt signs of clinical infection, by use of a factorial randomised design. The aim of the present study--the ORACLE Children Study I--was to determine the long-term effects on children of these interventions.

METHODS

We assessed children at age 7 years born to the 4148 women who had completed the ORACLE I trial and who were eligible for follow-up with a structured parental questionnaire to assess the child's health status. Functional impairment was defined as the presence of any level of functional impairment (severe, moderate, or mild) derived from the mark III Multi-Attribute Health Status classification system. Educational outcomes were assessed with national curriculum test results for children resident in England.

FINDINGS

Outcome was determined for 3298 (75%) eligible children. There was no difference in the proportion of children with any functional impairment after prescription of erythromycin, with or without co-amoxiclav, compared with those born to mothers who received no erythromycin (594 [38.3%] of 1551 children vs 655 [40.4%] of 1620; odds ratio 0.91, 95% CI 0.79-1.05) or after prescription of co-amoxiclav, with or without erythromycin, compared with those born to mothers who received no co-amoxiclav (645 [40.6%] of 1587 vs 604 [38.1%] of 1584; 1.11, 0.96-1.28). Neither antibiotic had a significant effect on the overall level of behavioural difficulties experienced, on specific medical conditions, or on the proportions of children achieving each level in reading, writing, or mathematics at key stage one.

INTERPRETATION

The prescription of antibiotics for women with preterm rupture of the membranes seems to have little effect on the health of children at 7 years of age.

FUNDING

UK Medical Research Council.

Childhood outcomes after prescription of antibiotics to pregnant women with spontaneous preterm labour: 7-year follow-up of the ORACLE II trial

BACKGROUND

The ORACLE II trial compared the use of erythromycin and/or amoxicillin-clavulanate (co-amoxiclav) with that of placebo for women in spontaneous preterm labour and intact membranes, without overt signs of clinical infection, by use of a factorial randomised design. The aim of the present study--the ORACLE Children Study II--was to determine the long-term effects on children after exposure to antibiotics in this clinical situation.

METHODS

We assessed children at age 7 years born to the 4221 women who had completed the ORACLE II study and who were eligible for follow-up with a structured parental questionnaire to assess the child's health status. Functional impairment was defined as the presence of any level of functional impairment (severe, moderate, or mild) derived from the mark III Multi-Attribute Health Status classification system. Educational outcomes were assessed with national curriculum test results for children resident in England.

FINDINGS

Outcome was determined for 3196 (71%) eligible children. Overall, a greater proportion of children whose mothers had been prescribed erythromycin, with or without co-amoxiclav, had any functional impairment than did those whose mothers had received no erythromycin (658 [42.3%] of 1554 children vs 574 [38.3%] of 1498; odds ratio 1.18, 95% CI 1.02-1.37). Co-amoxiclav (with or without erythromycin) had no effect on the proportion of children with any functional impairment, compared with receipt of no co-amoxiclav (624 [40.7%] of 1523 vs 608 [40.0%] of 1520; 1.03, 0.89-1.19). No effects were seen with either antibiotic on the number of deaths, other medical conditions, behavioural patterns, or educational attainment. However, more children whose mothers had received erythromycin or co-amoxiclav developed cerebral palsy than did those born to mothers who received no erythromycin or no co-amoxiclav, respectively (erythromycin: 53 [3.3%] of 1611 vs 27 [1.7%] of 1562, 1.93, 1.21-3.09; co-amoxiclav: 50 [3.2%] of 1587 vs 30 [1.9%] of 1586, 1.69, 1.07-2.67). The number needed to harm with erythromycin was 64 (95% CI 37-209) and with co-amoxiclav 79 (42-591).

INTERPRETATION

The prescription of erythromycin for women in spontaneous preterm labour with intact membranes was associated with an increase in functional impairment among their children at 7 years of age. The risk of cerebral palsy was increased by either antibiotic, although the overall risk of this condition was low.

FUNDING

UK Medical Research Council.

Estimating the effect of lung collapse and pulmonary shunt on gas exchange during breath-hold diving: the Scholander and Kooyman legacy

We developed a mathematical model to investigate the effect of lung compression and collapse (pulmonary shunt) on the uptake and removal of O(2), CO(2) and N(2) in blood and tissue of breath-hold diving mammals. We investigated the consequences of pressure (diving depth) and respiratory volume on pulmonary shunt and gas exchange as pressure compressed the alveoli. The model showed good agreement with previous studies of measured arterial O(2) tensions (Pa(O)(2)) from freely diving Weddell seals and measured arterial and venous N(2) tensions from captive elephant seals compressed in a hyperbaric chamber. Pulmonary compression resulted in a rapid spike in Pa(O)(2) and arterial CO(2) tension, followed by cyclical variation with a periodicity determined by Q(tot). The model showed that changes in diving lung volume are an efficient behavioural means to adjust the extent of gas exchange with depth. Differing models of lung compression and collapse depth caused major differences in blood and tissue N(2) estimates. Our integrated modelling approach contradicted predictions from simple models, and emphasised the complex nature of physiological interactions between circulation, lung compression and gas exchange. Overall, our work suggests the need for caution in interpretation of previous model results based on assumed collapse depths and all-or-nothing lung collapse models.

Enterobacteriaceae and related organisms isolated from shell eggs collected during commercial processing

In the United States, commercial shell eggs are washed and graded before retail. Since passage of the Egg Products Inspection Act in 1971, processing guidelines have been set to ensure that external and internal characteristics are maintained. However, less is known about how commercial processing affects the safety of shell eggs. To identify enteric bacteria entering plants and persisting throughout processing, eggs were collected from 3 US commercial shell egg-processing plants on 3 separate visits. On each plant visit, 12 eggs were collected from each of 12 sites along the processing line: accumulator, prewash rinse, first washer, second washer, sanitizer rinse, dryer, oiler, check detection/scales, 2 egg grader/packer head lanes, rewash belt entrance, and rewash belt exit. Each egg was sampled by a rinse technique, and the rinsate was plated onto violet red bile glucose agar with overlay for the detection and enumeration of Enterobacteriaceae. From each plate, up to 5 colonies were randomly selected and isolated for identification to genus or species by using biochemical tests. Several genera and species were detected at each of the 3 plants. Sites from which the greatest numbers of isolates were identified were those collected from eggs during preprocessing (accumulator, prewash rinse) or from eggs judged as dirty (rewash belt entrance or exit). Sites yielding the smallest number of isolates were those during or at the end of processing. Escherichia coli and Enterobacter spp. were isolated from each of the 9 plant visits. Other genera isolated from at least 1 of the 3 plants included Cedecea, Citrobacter, Erwinia, Hafnia, Klebsiella, Kluyvera, Leclercia, Morganella, Proteus, Providencia, Rahnella, Salmonella, and Serratia. Non-Enterobacteriaceae isolated and identified included Aeromonas, Chryseomonas, Listonella, Pseudomonas, Sphingobacterium, Vibrio, and Xanthomonas. All of the genera and species were recovered less frequently from fully processed eggs than from unwashed eggs, indicating that shell eggs are less contaminated with bacteria as a result of commercial washing procedures.

Identification of yeasts isolated from commercial shell eggs stored at refrigerated temperatures

Yeasts and molds can grow on or in eggs, causing spoilage. Washed and unwashed eggs (treatments) were collected aseptically on three separate days (replications) from a commercial processing facility and stored for 10 weeks at 4 degrees C. Ten eggs from each treatment were sampled weekly (110 eggs per treatment per replication). Yeasts and molds were enumerated from external shell rinses by plating onto acidified potato dextrose agar. Yeast colonies were picked randomly and stored for subsequent identification by gas chromatographic analysis of fatty acid methyl esters using the MIDI Microbial Identification System. Of 688 isolates analyzed, 380 were identified to genus or species. Genera identified by this method included Candida, Cryptococcus, Hansenula, Hyphopichia, Metschnikowia, Rhodotorula, Sporobolomyces, and Torulaspora. Candida spp. accounted for 84.5% (321 of 380) of the isolate identifications. Candida famata was the most prevalent species (n = 120), followed by Candida lusitaniae (n = 38). A group of 20 isolates was subjected to molecular or biochemical analyses for comparison with the MIDI results. Biochemical tests were performed using automatic and mini systems. Results of biochemical tests and ribosomal DNA sequencing were in agreement for 11 of the isolates, but only 7 of the 20 MIDI-identified isolates were in agreement with the sequencing results. C. famata, an anamorph of Debaryomyces hansenii var. hansenii, was the most commonly identified isolate by all methods. These data indicate that there was limited correlation between results obtained with the MIDI system and the information obtained from molecular databases. However, both systems were able to correctly identify C. famata, the species most often isolated throughout egg storage.

Enhanced suppression of hormonal and metabolic responses to stress by application of combined spinal-epidural and general anaesthesia compared with combined spinal general anaesthesia during colorectal surgery

The aim of the study was to determine the impact of combined spinal-epidural and general anesthesia (CSEGA) on the suppression of the hormonal and metabolic response to surgical stress and to compare it with the technique of combined spinal and general anesthesia (CSGA). Sixteen patients referred for elective colorectal surgery randomly divided into two groups on the basis of anesthesia (CSEGA and CSGA). Mean arterial blood pressure, heart rate, haemoglobin saturation, serum glucose, serum cortisol and urinary catecholamines (adrenaline, noradrenaline and dopamine) were determined at four distinct peri-operative time points. During the peri-operative period the overall haemodynamic and respiratory functions in patients that received CSEGA were superior compared to those in patients that received CSGA. Biochemical analysis revealed that in the sera of patients that received CSEGA the concentration of both glucose and cortisol was elevated to a lesser degree than that observed in the sera of patients that received CSGA. Furthermore, a significant reduction in post-operative urinary catecholamine (adrenaline and noradrenaline) excretion was apparent in the CSEGA group. We conclude that CSEGA is a more suitable form of combined anaesthesia for colorectal surgery with a clear advantage of a blunted surgery-mediated neuro-endocrine stress response.

Storage effects on dielectric properties of eggs from 10 to 1800 MHz

The dielectric constant and loss factor of egg albumen and egg yolk over the frequency range from 10 to 1800 MHz were measured at 24 degrees C at weekly intervals during 5-wk storage at 15 degrees C. Moisture and ash contents of albumen and yolk, as well as Haugh unit and yolk index, were also measured. The dielectric constant and loss factor of albumen were higher than those of yolk. Linear relationships were evident between the log of frequency, below about 1000 MHz, and the log of loss factor of albumen as well as that of yolk. The dielectric constants of albumen and yolk at 10 MHz were lower than those of fresh albumen and yolk when eggs were stored at 15 degrees C for 1 wk. However, after 2 wk in storage these dielectric constants rose and remained at higher levels for the rest of the 5-wk period. At frequencies of 100 MHz and higher, the dielectric constant was essentially constant during the entire storage period. Storage had much less influence on the loss factor of either albumen or yolk. In general, the moisture content and ash content of albumen and yolk decreased slightly as eggs aged. The moisture content of yolk increased somewhat with storage, and there was a corresponding decrease in albumen moisture content. The freshness qualities, Haugh unit and yolk index, also decreased as eggs aged. No obvious correlation between dielectric properties and moisture content, ash content, Haugh unit, or yolk index was observed.

To what extent might N2 limit dive performance in king penguins?

A mathematical model was used to explore if elevated levels of N2, and risk of decompression sickness (DCS), could limit dive performance (duration and depth) in king penguins (Aptenodytes patagonicus). The model allowed prediction of blood and tissue (central circulation, muscle, brain and fat) N2 tensions (P(N2)) based on different cardiac outputs and blood flow distributions. Estimated mixed venous P(N2) agreed with values observed during forced dives in a compression chamber used to validate the assumptions of the model. During bouts of foraging dives, estimated mixed venous and tissue P(N2) increased as the bout progressed. Estimated mean maximum mixed venous P(N2) upon return to the surface after a dive was 4.56+/-0.18 atmospheres absolute (ATA; range: 4.37-4.78 ATA). This is equivalent to N2 levels causing a 50% DCS incidence in terrestrial animals of similar mass. Bout termination events were not associated with extreme mixed venous N2 levels. Fat P(N2) was positively correlated with bout duration and the highest estimated fat P(N2) occurred at the end of a dive bout. The model suggested that short and shallow dives occurring between dive bouts help to reduce supersaturation and thereby DCS risk. Furthermore, adipose tissue could also help reduce DCS risk during the first few dives in a bout by functioning as a sink to buffer extreme levels of N2.

Use of evidence in economic decision models: practical issues and methodological challenges

This paper outlines the current 'state of play' regarding the use of evidence in decision modelling and highlights both practical issues and methodological challenges related to identifying, combining and reporting evidence to inform decision model parameters and structure. Based on discussions at two MRC HSRC-funded workshops consisting of 37 experts from a range of disciplines (i.e. decision-makers, health economists, information specialists, operations researchers and statisticians), it aims to derive a multi-disciplinary standpoint on the appropriate use of evidence in economic decision models and, where applicable, offer some suggestions for good modelling practice. Gaps in the established methodology knowledge base are identified for future research.

A comparison of sevoflurane-fentanyl and neuroleptic anaesthesia for laparoscopic cholecystectomy of mildly obese patients

The current study was formulated to evaluate the advantages and disadvantages of sevoflurane-fentanyl and neuroleptic anaesthesia for laparoscopic cholecystectomy surgery of mildly obese patients. Laparoscopic cholecystectomy was performed using either sevoflurane-fentanyl or neuroleptic anaesthesia. Intra-operative haemodynamic stability, surgical duration, awakening time, severity of post-operative pain and hormonal stress parameters (serum and urinary cortisol, serum insulinlike growth factor and serum insulin) were determined. The duration of both surgery and patient hospitalisation were similar in both study groups. Patients that received sevoflurane-fentanyl exhibited a significantly shorter awakening time compared to neuroleptic anaesthesia. In addition, the same group of patients had less post-operative complications (nausea, vomiting, urinary retention and respiratory insufficiency) despite more abdominal pain. The severity of postoperative pain and the requirement of additional analgesia (up to 12 hours post-surgery) were greater in patients that received sevoflurane-fentanyl. The serum and urinary cortisol concentrations were significantly increased in post-operative patients that received neuroleptic anaesthesia whereas the insulin-like growth factor-I concentration in both study groups significantly decreased post-operatively. Our results clearly show that neuroleptic anaesthesia attenuates the stress response to laparoscopic cholecystectomy to a lesser extent than sevoflurane-fentanyl. The latter anaesthesia is recommended for laparoscopic cholecystectomy of mildly obese patients.

Adult mesenchymal stem cells: differentiation potential and therapeutic applications

Adult mesenchymal stem cells (MSCs) are a population of multipotent cells found primarily in the bone marrow. They have long been known to be capable of osteogenic, adipogenic and chondrogenic differentiation and are currently the subject of a number of trials to assess their potential use in the clinic. Recently, the plasticity of these cells has come under close scrutiny as it has been suggested that they may have a differentiation potential beyond the mesenchymal lineage. Myogenic and in particular cardiomyogenic potential has been shown in vitro. MSCs have also been shown to have the ability to form neural cells both in vitro and in vivo, although the molecular mechanisms underlying these apparent transdifferentiation events are yet to be elucidated. We describe here the cellular characteristics and differentiation potential of MSCs, which represent a promising stem cell population for future applications in regenerative medicine.

Pathogen prevalence and microbial levels associated with restricted shell eggs

Restricted shell eggs that do not meet quality standards for retail but maintain acceptable quality for inclusion in further processed eggs are often diverted to further processing. A study was conducted to characterize the microbiological populations present on and in these eggs. On a single day, restricted eggs were collected from three shell egg processing plants a total of three times (replicates). Six shells or egg contents were combined to create a pool. Ten pools of shells and contents were formed for each plant per replicate. Shells and membranes were macerated in 60 ml of diluent. Contents were stomacher blended to form a homogeneous mixture. Total aerobic microorganisms and Enterobacteriaceae were enumerated. The prevalence of Salmonella, Campylobacter, and Listeria was determined by cultural methods. Average aerobic counts were 4.3 log CFU/ml for the shells and 2.0 log CFU/ml for the contents. There were plant x replicate differences for both (P < 0.05 and P < 0.01, respectively). The average Enterobacteriaceae level associated with the shell was 2.4 log CFU/ml and less than 0.1 log CFU/ml for the egg contents, with 36.7% of the samples being positive. One shell sample (0.5% of total samples) was Campylobacter positive. Two shell samples (1.1% of total samples) were Salmonella positive. Twenty-one percent of samples were positive for Listeria (33 shells and 5 contents). Although current pasteurization guidelines are based on Salmonella lethality, the results of this study reiterate the need to revisit the guidelines to determine the effectiveness for other pathogenic species.

Effects of Genetic Selection on Behavioral Profiles of Single Comb White Leghorn Hens Through Two Production Cycles

Four layer genetic stocks consisting of 3 Ottawa control strains (5, 7, and 10) and a commercial laying stock (CCS) were utilized to evaluate potential changes in behavioral profiles due to the effects of genetic selection through 2 production cycles. The Ottawa strains were started as random bred strains from the crosses of several popular commercial layers in 1950, 1959, and 1972, and the commercial strain used herein was from calendar year 1993, and its ancestors were involved in the formation of all of the random bred strains. The behavior study utilized 2 replicates from each strain that contained 4 cages, 6 hens/cage, for a total of 192 hens. Behavioral observations were recorded on 2 consecutive days beginning at 22 wk of age and every 28 d thereafter during the first production cycle, the molt period, and the second production cycle through 90 wk of age and periodic feather and Hansen's test scores recorded. Behavior profiles were similar between the control strains and the CCS, indicating that long-term genetic selection by commercial egg-type breeding firms to enhance production parameters has had no impact on laying strain behavior patterns. Appetitive behaviors were not affected by strain. During the molt, hens had reduced (P < 0.05) feeding and drinking frequencies in comparison with those observed during the first and second cycles. The data indicated that hens pecked inedible objects at a greater (P < 0.0001) frequency during the first cycle and molt than during the second cycle. Fearfulness scores were only influenced by production phase with the molt having the highest (P < 0.01) score of 3.46. Strain or production phase did not influence the frequency of aggressive and submissive acts.

Botulinum Toxin B Is Not an Effective Treatment of Refractory Overactive Bladder

OBJECTIVES

To determine the efficacy and safety of botulinum toxin-B (BTX-B) in two groups of patients with urodynamically proven idiopathic detrusor overactivity (IDO) or neurogenic DO (NDO) refractory to conservative treatment.

METHODS

This was a nonrandomized, prospective study. We diluted 5000 U of BTX-B in 20 mL of normal saline and injected it at 20 sites around the bladder, avoiding the trigone. The data collected at recruitment and 10 and 26 weeks postoperatively included number of incontinent episodes, frequency, and nocturia, King's Health Questionnaire score, and the urodynamic parameters of volume at the first overactive contraction and maximal cystometric capacity.

RESULTS

A total of 25 patients were recruited, 20 with IDO and 5 with NDO. Only 7 patients, all with IDO, reported symptomatic improvement at the 10-week assessment. The symptoms had returned in these 7 patients at a median of 136 days (range 106 to 151) after injection. Of the remaining 20 patients, 16 (13 with IDO and 3 with NDO) thought an initial improvement had occurred but it had worn off or was wearing off by the first assessment. Two patients (both with NDO) reported no improvement.

CONCLUSIONS

BTX-B had a limited duration of action, with most of its symptomatically beneficial effects wearing off by 10 weeks in most of our patients. The short duration of action for BTX-B suggests it is unlikely to gain widespread use in the treatment of DO.

The anti-oxidative defence system in the isolated rat uterus during spontaneous rhythmic activity

Possible interactions between nitric oxide donors, reactive oxygen species and anti-oxidative defence enzymes led us to determine the activities of anti-oxidative defence enzymes in isolated uterine smooth muscle before and after spontaneous rhythmic activity ex vivo. For our experiments we used isolated uteri from female Wistar rats. Our results showed an increase in total superoxide dismutase (SOD) and Mn SOD activities in uterine smooth muscle after spontaneous contractions when compared with nonexercised uterine smooth muscle. The activity of catalase (CAT) and glutathione preoxidase (GSH-Px) were also increased. No statistically significant changes in the activities of glutathione reductase (GR) and CuZn SOD were found. It is known that an organism's anti-oxidative defence system (guarding against excessive reactive oxygen species generation) requires balanced increments in its individual anti-oxidative enzyme activities rather than increases in the activity of only some enzymes without increases in others. Thus, we may conclude that some adaptive responses are found in exercised uterine smooth muscle but are not complete. Therefore, our results indicate that changes in anti-oxidative enzyme activities may influence the results of the examination of substances ex vivo.

The influence of laparoscopic and open surgery on the concentration and structural modifications of insulin-like growth factor binding protein 3 in the human circulation

Insulin-like growth factor binding protein 3 (IGFBP-3) is the most abundant insulin-like growth factor binding protein in the circulation. The aim of the present work was to investigate the influence of surgery (laparoscopy and open) on the concentration and carbohydrate content of IGFBP-3. The concentration of IGFBP-3 was measured using an immunoradiometric assay (IRMA), its protein profile was characterised using immunoblotting and its sialic acid content was examined by means of Sambucus nigra agglutinin (SNA) affinity chromatography. The concentration of IGFBP-3 was significantly (p < 0.001) lower in preoperative patients compared with healthy subjects. Only patients that underwent open surgery showed a further significant decrease in the concentration of IGFBP-3. Immunoblotting detected two intact IGFBP-3 isoforms, as well as proteolytic fragments. SNA-affinity chromatography showed that in patients that underwent surgery the ratio between the two IGFBP-3 glycoforms was lower than the ratio in healthy subjects. Patients with gallbladder inflammation that underwent laparoscopy had an increased percentage of specifically bound IGFBP-3 to SNA compared with healthy subjects. Our conclusion is that open surgery decreased the level of IGFBP-3 compared with laparoscopy, whereas patients with gallbladder inflammation that underwent laparoscopy had an increased content of sialic acid in IGFBP-3.

Antimicrobial Resistance in Salmonella and Escherichia coli Isolated from Commercial Shell Eggs

The development of antimicrobial resistance in bacteria has become a global problem. Isolates of Salmonella and Escherichia coli recovered from shell egg samples, collected at 3 commercial plants, were analyzed for resistance to 16 antimicrobial agents (n=990). Eggs were sampled by rinsing in a saline solution. Pooled samples were preenriched in buffered peptone water and then selectively isolated using standard broths and agars. Salmonella-positive isolates were serogrouped immunologically before being serotyped. Enterobacteriaceae were enumerated from individual samples using violet red bile glucose agar plates. Escherichia coli were identified biochemically from presumptive Enterobacteriaceae isolates. Salmonella and generic E. coli antimicrobial-susceptibility testing was conducted using a semiautomated broth microdilution system. More resistance was observed in the Salmonella isolates (n=41) than in the E. coli isolates (n=194). Salmonella Typhimurium was the most prevalent (69.0%) serotype and demonstrated the greatest multiple resistance. Salmonella Kentucky, the least prevalent (5.0%) serotype recovered, was the most susceptible. Although 34.1% of the Salmonella serotypes were susceptible to all antimicrobial agents, 60.1% were resistant to 11 or more compounds. Many Salmonella isolates exhibited resistance to tetracycline (63.4%), nalidixic acid (63.4%), and streptomycin (61.0%). Most E. coli isolates (73.2%) were susceptible to all antimicrobial drugs. Many E. coli isolates exhibited resistance to tetracycline (29.9%), streptomycin (6.2%), and gentamicin (3.1%). Only 1% of the E. coli isolates were resistant to 4 antimicrobial agents. These data indicate that shell eggs can harbor resistant foodborne and commensal bacteria; among Salmonella isolates, resistance was serotype-dependent.

Meta-analysis of mortality and cancer incidence among workers in the synthetic rubber-producing industry

Production of synthetic rubber involves exposure to several potentially harmful chemicals. The authors carried out a systematic review and meta-analysis of cohort studies of workers in the rubber-producing industry. Data were obtained from computerized literature searches of several databases from their inception through December 2003. The reference lists of identified articles were inspected for further relevant articles. The authors conducted random-effects meta-analyses of log standardized mortality ratios (SMRs)/standardized incidence ratios. Heterogeneity between study results was explored through subgroup analyses and meta-regression on cohort demographic factors and study quality indicators. The authors identified 36 published articles reporting information on 31 different cohort groups. The meta-SMR was 0.86 (95% confidence interval (CI): 0.82, 0.91) for all-cause mortality (28 cohorts) and 0.94 (95% CI: 0.89, 1.01) for all malignant neoplasms (27 cohorts). Heterogeneity was observed for these endpoints and for the majority of disease-specific outcomes. Statistically significant excesses were observed for diabetes (meta-SMR=1.36, 95% CI: 1.17, 1.59) (five cohorts) and leukemia (meta-SMR=1.21, 95% CI: 1.03, 1.43) (16 cohorts), the latter particularly for persons working exclusively in nontire manufacturing (meta-SMR=1.70, 95% CI: 1.14, 2.54) (four cohorts). Excesses highlighted in previous narrative reviews were not substantiated. Interpretation of these results is complicated by substantial unexplainable heterogeneity; small excesses in specific mortality outcomes may have been disguised by the healthy worker effect.