Recovery of Salmonella and Escherichia coli from commercial egg shells and effect of translucency on bacterial penetration in eggs

This experiment was conducted to study the prevalence of Salmonella and Escherichia coli (E. coli). from the surface of egg shells, egg shell membranes or pores, and internal contents from unwashed eggs collected from commercial caged layer farms in Australia. Egg shell swabs, shell crush and egg internal contents (yolk and albumen) of an individual egg were processed for bacteriological examination. Salmonella spp. were not detected from any of the egg shell surfaces, egg shell crush or egg internal contents. Thirty five E. coli isolates were isolated from the egg shell surface. Ten E. coli strains were also isolated from shell crush. However, the internal contents of eggs appeared to be sterile. Polymerase chain reaction was performed on forty-five E. coli isolates using primers for heat stable enterotoxin genes A and B (STa and STb) and also for colicin V gene (cvaC). STa gene was detected in four E. coli isolates isolated from egg shell surfaces. All the E. coli isolates were negative for STb and cvaC genes. These data provide useful information regarding the prevalence of virulent E. coli and Salmonella spp. on and in unwashed eggs collected from layer farms. These data also suggest that unwashed eggs collected from caged layer farms are unlikely to be sources of Salmonella outbreaks. Egg shell translucency could be due to changes in the mammillary layer and mamillary cores during the early phases of egg shell formation and has the potential to increase the incidence of microcracks in egg shells, and hence, may be responsible for bacterial penetration. There was a significant correlation between egg shell translucency and egg shell penetration by Salmonella Infantis and E coli. Both strains of bacteria were able to penetrate the translucent egg shells even at very low doses. The penetration, however, was hindered in both translucent and non translucent eggs at 4 degrees C, as compared with room temperature which highlights the importance of storage of eggs at refrigerated temperatures.

Effectiveness of varicella vaccine in children infected with HIV

Although varicella vaccine is given to clinically stable human immunodeficiency virus (HIV)-infected children, its effectiveness is unknown. We assessed its effectiveness by reviewing the medical records of closely monitored HIV-infected children, including those receiving highly active antiretroviral therapy (HAART) between 1989 and 2007. Varicella immunization and development of varicella or herpes zoster were noted. Effectiveness was calculated by subtracting from 1 the rate ratios for the incidence rates of varicella or herpes zoster in vaccinated versus unvaccinated children. The effectiveness of the vaccine was 82% (95% confidence interval [CI], 24%-99%; P = .01) against varicella and was 100% (95% CI, 67%-100%; P < .001) against herpes zoster. When the analysis was controlled for receipt of HAART, vaccination remained highly protective against herpes zoster.

Heterologous Prime-Boost HIV-1 Vaccination Regimens in Pre-Clinical and Clinical Trials

Currently, there are more than 30 million people infected with HIV-1 and thousands more are infected each day. Vaccination is the single most effective mechanism for prevention of viral disease, and after more than 25 years of research, one vaccine has shown somewhat encouraging results in an advanced clinical efficacy trial. A modified intent-to-treat analysis of trial results showed that infection was approximately 30% lower in the vaccine group compared to the placebo group. The vaccine was administered using a heterologous prime-boost regimen in which both target antigens and delivery vehicles were changed during the course of inoculations. Here we examine the complexity of heterologous prime-boost immunizations. We show that the use of different delivery vehicles in prime and boost inoculations can help to avert the inhibitory effects caused by vector-specific immune responses. We also show that the introduction of new antigens into boost inoculations can be advantageous, demonstrating that the effect of `original antigenic sin' is not absolute. Pre-clinical and clinical studies are reviewed, including our own work with a three-vector vaccination regimen using recombinant DNA, virus (Sendai virus or vaccinia virus) and protein. Promising preliminary results suggest that the heterologous prime-boost strategy may possibly provide a foundation for the future prevention of HIV-1 infections in humans.

N0539 Phase II Trial of Fulvstrant and Bevacizumab in Patients with Metastatic Breast Cancer Previously Treated with an Aromatase Inhibitor: A North Central Cancer Treatment Group Trial

Background: Treatment of aromatase refractory metastatic breast cancer (MBC) is difficult and challenging. Estrogen receptor (ER) resistance causes enhanced expression of the vascular endothelial growth factor (VEGF).Several studies have shown that the ER interacts with the VEGF pathway and is an important mechanism of resistance. Therefore we embarked on a phase II study of fulvestrant, a complete ER suppressor and bevacizumab, a well studied VEGF monoclonal antibody in aromatase refractory MBC patients. Methods: A single stage phase II study with an interim analysis of fulvestrant and bevacizumab was conducted with these objectives: 6 month progression-free survival rate (PFS), tumor response, toxicity, and overall survival. Regimen: fulvestrant 250 mg day1 and 15 (cycle 1) then day 1 (cycle 2 and beyond) and bevacizumab 10mg/kg days 1 and 15 of each 4 weeks is a cycle. Results: At the time of interim analysis, 11/20 evaluable patients achieved 3-month progression-free survival status while remaining on treatment for at least 3 months, not meeting the protocol specified efficacy requirements and thus halting accrual. 36 patients were enrolled from September 2007-December 2008; 33 patients were evaluable. Number of prior metastatic chemotherapy regimens: 0 in 26 patients and 1 in 7 patients. 22 (67%) patients received prior hormonal therapy in the metastatic setting. 18 (55%) had measurable disease. A median of 6 cycles (range 1-19) were administered. 12/33 evaluable patients (95% CI:20-55%) achieved 6-month progression-free survival status while remaining on treatment for a least 6 months. Among 18 patients with measurable disease, 2 (11%) patients CI:1.4-35%) had a confirmed tumor reponse (both PR). Additionally, 2 patients had stable disease for greater than 6 months, for a clinical benefit rate of 22%. Median follow up was 8.5 months (range 1.7-17.5 months). Median progression-free survival was 6.2 months (95% CI:5.4-10.1 months). The 6 -month overall survival rate was 84.8% (95% CI 73.5-98%). The median dose level administered was 250 mg for fulvestrant and 10 mg/kg for bevacizumab for cycles 1-19. The most common grade 3/4 adverse events (AEs) were hypertension 2 (6%), headache pain 2 (6%), and confusion 2 (6%). There was 1 grade 5 central nervous system hemorrhage. 13 (39%) patients experienced a grade 3 non-hematologic AE and 4 (12%) experience a grade 4+ non-hematologic AE. Conclusion: Fulvestrant/bevacizumab is safe and tolerable. Although this regimen did not meet its statistical endpoint, 22% of evaluable patients with aromatase refractory diesease achieved clinical benefit with minimal toxicity.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4096.

Clinical practice guidelines for the diagnosis and management of intravascular catheter-related infection: 2009 Update by the Infectious Diseases Society of America

These updated guidelines replace the previous management guidelines published in 2001. The guidelines are intended for use by health care providers who care for patients who either have these infections or may be at risk for them.

Meningioma presenting with transient ischaemic attacks

A case of sphenoid wing meningioma mimicking the presentation of a transient ischaemic attack (TIA) is described. Based on findings from neuroimaging in this case, possible explanations of the mechanism of this uncommon presentation of meningiomas are discussed and the literature is reviewed.

Posterior fossa arachnoid cyst presenting with unilateral tremor

A rare case of unilateral benign essential tremor is presented that responded to surgical excision of a posterior fossa arachnoid cyst.

N0337: Phase II study of capecitabine in combination with vinorelbine and trastuzumab for the first or second treatment of HER2+ metastatic breast cancer

1020

Background: Trastuzumab-containing regimes have dramatically improved outcome of patients with HER2+ breast cancer. Efforts to improve efficacy and tolerability of combination regimens with this monoclonal antibody are important for patient care. Thus, we conducted a multi-institutional phase II study of a triplet combination in patients eligible to receive either first- or second-line treatment for HER2+ metastatic breast cancer (MBC). Methods: A phase II study designed to test that the true confirmed response rate (CRR) was at most 45% versus a true CRR of at least 65% was done (March 2005-June 2008). This design required that at least 25/45 confirmed responses in evaluable patients for the treatment to be considered promising. Patients received capecitabine 825 mg/m2 po (days 1–14), vinorelbine intravenously (IV) 25 mg/m2 days 1 and 8 every 3 weeks and trastuzumab IV 8mg/kg day 1, week 1, and then 6 mg/kg q 3 weeks. Tissue and blood have been collected for future studies on biomarkers. Results: 47 women were accrued, one patient cancelled participation prior to receiving any study drug, and another had a major protocol violation. 45 patients were evaluable and 30 (67%) achieved a confirmed response, (26 patients, 58% had a confirmed partial response and 4 patients, 9% had a confrimed complete response). Median progression free survival was 11.3 months (95% CI 8.4–23.2 months), median overall survival was 27.2 months (95% CI: 26.6-NA months), and among the 30 responders, the median duration of response time was 15.5 months (95% 7.7–26.1 months). The most common grade 3 events include neutropenia 61%, fatigue 13%, skin reaction-hand-foot 11%, and leukopenia 11%. Alopecia was not noted with this regimen. Conclusions: This triplet combination is effective, safe, and is promising in patients with HER2+ MBC. A phase III study should be conducted to compare the best doublet with this triplet combination whether this would lead to better clinical outcomes.

[Table: see text]

Preclinical and clinical development of a multi-envelope, DNA-virus-protein (D-V-P) HIV-1 vaccine

The human immune system has evolved to recognize antigenic diversity, a strength that has been harnessed by vaccine developers to combat numerous pathogens (e.g., pneumococcus, influenza virus, rotavirus). In each case, vaccine cocktails were formulated to include antigenic variants of the target. To combat HIV-1 diversity, we assembled a cocktail vaccine comprising dozens of envelopes, delivered as recombinant DNA, vaccinia virus, and protein for testing in a clinical trial. One vaccinee has now completed vaccinations with no serious adverse events. Preliminary analyses demonstrate early proof-of-principle that a multi-envelope vaccine can elicit neutralizing antibody responses toward heterologous HIV-1 in humans.

Prophylactic antibiotics reduce morbidity due to septicemia during intensive treatment for pediatric acute myeloid leukemia

BACKGROUND

The aim of this study was to determine whether antibiotic prophylaxis during periods of neutropenia reduced streptococcal (S. viridans) sepsis and overall bacterial sepsis.

METHODS

The authors reviewed outcomes of 78 evaluable patients who were consecutively treated for acute myeloid leukemia (AML) from October 2002 through January 2007. Several successive prophylactic antibiotic regimens were used. All patients received antifungal prophylaxis with oral voriconazole.

RESULTS

Oral cephalosporins did not significantly reduce the odds of bacterial sepsis (P = .81) or streptococcal (S. viridans) sepsis (P = .90) relative to no prophylaxis. Intravenous (iv) cefepime completely prevented streptococcal (S. viridans) sepsis and reduced the odds of bacterial sepsis 91% (P < .0001) relative to no prophylaxis, but resistant gram-negative bacteria emerged in 2 patients. Vancomycin with oral ciprofloxacin or a cephalosporin reduced the odds of bacterial sepsis by 93% (P < .0001) and streptococcal (S. viridans) sepsis by 99% (P < .0001). The fungal infection rate did not differ significantly between patients who did and did not receive antibiotic prophylaxis (1.0 per 1000 patient-days for both groups). The observed reduction in average hospital days per chemotherapy course for patients given vancomycin regimens or cefepime was 5.7 (P < .0001) and 4.1 (P = .0039) days, respectively. No reduction was observed with oral cephalosporins (P = .10). Furthermore, vancomycin regimens or cefepime were associated with a 20% reduction in healthcare charges (P = .0015) relative to using no antibiotics. One patient, who was on oral cefuroxime alone, died of septicemia.

CONCLUSIONS

Prophylaxis with intravenous cefepime or a vancomycin regimen, and voriconazole, reduced morbidity in children with AML, and resulted in dramatic decreases in the incidence of septicemia and hospitalization days.

A randomised comparison of the single use LMA Flexible with the reusable LMA Flexible in paediatric dental day-case patients

In this study we compared the performance of the single use flexible laryngeal mask airway (LMA Flexible) with the original reusable LMA Flexible in paediatric dento-alveolar day-case surgery. The aim of the study was to determine whether these two supraglottic airway devices were clinically equivalent when used for simple dental extractions in children under general anaesthesia. This randomised comparative trial in 100 healthy children used first attempt airway insertion success as its primary outcome measure. Secondary outcomes included the adequacy of ventilation, incidence of airway obstruction and the requirement for device manipulation and the incidence of adverse airway outcomes during recovery from anaesthesia. No difference was found between the devices in first attempt insertion success rate (94% with reusable LMA Flexible and 90% with single use LMA Flexible, p = 0.358), and ease of insertion was also similar (p = 0.5). Both devices performed equally well during surgery, with no significant differences in episodes of intra-operative airway compromise (p = 0.387), and both the single use and reusable LMA Flexible displayed excellent recovery characteristics, with no occurrences of emergence airway obstruction. No blood was discovered within the inner LMA tube shaft in either device, implying that both protected against tracheobronchial soiling. We conclude therefore that the single use LMA Flexible is an acceptable alternative to the reusable LMA Flexible.

An introduction to Toll-like receptors and their possible role in the initiation of labour

Toll-like receptors (TLR) have emerged as key upstream mediators of inflammation at many tissue sites in humans. Inflammatory processes are involved in the process of parturition suggesting that TLR activity within gestation-associated tissues might have an important role in the initiation and/or maintenance of normal term labour and in various pathological states of pregnancy such as infection-associated preterm labour. Either TLRs or their signalling molecules might be excellent therapeutic targets for prevention of preterm labour.

Long-term safety and efficacy of a once-daily regimen of emtricitabine, didanosine, and efavirenz in HIV-infected, therapy-naive children and adolescents: Pediatric AIDS Clinical Trials Group Protocol P1021

BACKGROUND

Compliance with complex antiretroviral therapy regimens is a problem for HIV-1-infected children and their families. Simple, safe, and effective regimens are important for long-term therapeutic success.

METHODS

A novel, once-daily dosing regimen of 3 antiretroviral drugs, emtricitabine, didanosine, and efavirenz, was tested in 37 therapy-naive HIV-infected children and adolescents between 3 and 21 years of age (inclusive). Subjects were followed for > or = 96 weeks on an intention-to-treat basis. Signs, symptoms, plasma HIV-1 RNA viral load, CD4 counts, and safety laboratories were followed regularly. End points were the proportion of subjects with plasma HIV < 400 or 50 HIV copies per mL and safety and tolerability of the regimen.

RESULTS

Thirty-seven subjects enrolled at 16 sites. Two subjects with rashes during the first 2 weeks of therapy were the only adverse events leading to study-drug discontinuation. Other early (before protocol-scheduled conclusion) study discontinuations included 3 viral failures on treatment and 5 patients who stopped therapy for apparently nonmedical reasons. Possible drug-related adverse events included 1 grade 4 low-glucose and 5 varied grade 3 events. There were no deaths. Virologic outcomes demonstrated that 32 (85%) of 37 subjects achieved viral suppression to < 400 RNA copies per mL, and 26 (72%) of 37 subjects maintained sustained suppression at < 50 copies per mL through week 96. The median baseline CD4 count was 310 per microL (17%), which increased at week 96 by a median of +329 cells per microL (by +18% CD4). Pharmacokinetic results were as predicted for emtricitabine, didanosine, and efavirenz capsules, whereas efavirenz concentrations in children receiving efavirenz oral solution were lower than anticipated, requiring a dose escalation after the planned assessment point.

CONCLUSIONS

A once-daily regimen of emtricitabine, didanosine, and efavirenz proved to be safe and tolerable and demonstrated good immunologic and virologic efficacy in this 2-year study.

Population pharmacokinetics of micafungin in pediatric patients and implications for antifungal dosing

The echinocandins potentially have an important role in treatment of infections caused by Candida spp. and Aspergillus spp. in immunocompromised children. However, there are no population pharmacokinetic models of the echinocandins for pediatric patients. The safety and descriptive pharmacokinetics of micafungin in children were recently reported. However, a population pharmacokinetic model in children is needed in order to accurately determine the dosage of micafungin that produces an equivalent magnitude of drug exposure to that observed in adults. In order to explore the effect of weight on micafungin pharmacokinetics, a standard two-compartment pharmacokinetic model, a linear model, and an allometric power model were developed. For all three models, the fit to the data was excellent, with comparable measures of precision and bias. However, the superior log-likelihood value of the allometric power model suggested that it best reflected the data and was therefore chosen for a more detailed analysis of the magnitude and pattern of drug exposure which develop following the administration of micafungin. The allometric power model suggested that clearance in smaller children is higher than that predicted on the basis of weight alone. Consequently, a degree of dosage increase is required in smaller children to ensure comparable levels of drug exposure to those observed in larger children and adults. The allometric power model developed in this study enables identification of pediatric dosage regimens of micafungin which, based upon Monte Carlo simulations, result in equivalent drug exposures to those observed in adults, for which antifungal efficacy has been established.

Translational correlates, including outcome for patients with ER-/PR-/HER2- (triple negative (TNeg)) disease from N0234, a phase II trial of gemcitabine and erlotinib for pts with previously treated metastatic breast cancer (MBC)

1071

Background: N0234 is a phase II trial of gemcitabine at 1000 mg/m2 days 1 and 8 of a 21 day cycle and erlotinib at 150 mg daily in patients with previous therapy with either an anthracycline or a taxane for MBC. A partial response (PR) rate of 17% has been reported (ASCO 2005). Recent information suggests that over-expression of the EGFR pathway is frequent in patients with TNeg MBC. Methods: Tissue and serum were obtained for translational studies of ER, PR, HER2, and proteins related to EGFR pathway on tissue using immunohistochemistry; CK19, mammoglobin, and TTK on circulating tumor cells (CTCs). Markers were evaluated centrally, blinded to patient outcome. Complete data were available in 57 of 59 eligible patients; 20/57 patients (pts) were TNeg. Results: A PR rate of 25% and clinical benefit rate (PR + stable disease > 6 months)of 25% was observed in TNeg pts as compared to a PR rate of 14% (p = 0.30) and clinical benefit rate 22% (p= 0.75) for non-TNeg pts. Median progression free survival 72 days vs 98 days (p=0.13) and overall survival 227 days vs 738 days (p<0.001) were shorter for TNeg pts. Translational results for the EGFR pathway proteins and CTC analysis is forthcoming. Conclusions: The combination of gemcitabine and erlotinib appears to be as active in the non-TNeg and TNeg subset of patients on this trial. TNeg patients had an inferior clinical result, confirming the poor outcome seen in these patients. Data for the remaining biomarkers potentially predictive of activity will be presented. Supported by CA-25224, CA-37404.

[Table: see text]

Patient dose from 3D rotational neurovascular studies

The use of image-guided interventional radiological techniques is increasing in prevalence and complexity. Imaging system developments have helped improve the information available to interventionalists to plan and guide procedures. Information on doses to patients resulting from alternative imaging techniques or protocols is useful for both the process of justifying particular procedures and in optimizing the resultant exposures. Such information is not always available, especially for new or developing imaging techniques. We have undertaken a study of doses to patients associated with two alternative imaging methods for pre-intervention assessment of intracranial aneurysms. In the first technique the aneurysm is assessed from a series of digital subtraction angiography (DSA) runs taken at different imaging projections. The second technique involved acquiring images from one single image run while the imaging system rotated 180 degrees around the patient's head. In this technique, the aneurysm was then evaluated from a 3D reconstruction of the projection images. Effective doses were calculated using a computer model to simulate the exposure geometry and parameters. The mean dose from the DSA protocol used at our centre was 3.4 mSv and from the 3D rotational angiography (RA) technique was 0.20 mSv.

Safety of bevacizumab plus chemotherapy as first-line treatment of patients with metastatic colorectal cancer: Updated results from a large observational registry in the US (BRiTE)

3536

Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy for patients with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of patients with mCRC receiving BV plus first-line chemotherapy. Safety and efficacy information in unselected patients with mCRC are collected. Chemotherapy regimen choice is at the physician’s discretion. Methods: To facilitate and evaluate enrollment of a typical community-based mCRC population, eligibility criteria were minimized. Cohort demographics were consistent with the NCI Surveillance, Epidemiology, and End Results (SEER) database for mCRC. Patients are followed for up to 3 years, and safety data including targeted BV-associated serious adverse events (SAEs) are updated every 3 months (mo). Results are based on descriptive analyses and are not adjusted for propensity of treatment, baseline characteristics, and treatment effects. Results: 1968 patients were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo by Nov 4, 2005. SAEs were reported in 12.0% of patients including gastrointestinal perforation (GIP) (1.7%), postoperative bleeding/wound healing complications (1.2%), arterial thromboembolic events (ATE) (2.1%), and grade 3–4 bleeding (1.9%). 3.2% of patients discontinued BV due to a BV-related toxicity, most commonly bleeding. For patients with the respective event(s), median time to first event was 2.1 mo for GIP, 3.5 mo for ATE and 4.0 mo for grade 3–4 bleeding. 8.9% of patients with no history of hypertension (HTN) developed HTN requiring medication and 6.2% of patients who had HTN requiring medication at baseline experienced worsening of their HTN while on study treatment. Conclusions: In this unselected population of patients with mCRC, the safety profile of BV plus various chemotherapy regimens appears consistent with that observed in the pivotal BV trial. Overall discontinuation of BV due to a BV-related toxicity was uncommon. In this large community-based observational registry, no new BV associated safety issues have been identified.

[Table: see text]

Risk factors for gastrointestinal perforations in patients with metastatic colorectal cancer receiving bevacizumab plus chemotherapy

3535

Background: Bevacizumab (BV) prolongs overall survival and progression-free survival when added to standard chemotherapy in patients (pts) with metastatic colorectal cancer (mCRC). BRiTE is a large, community-based observational registry of pts with mCRC receiving BV plus first-line chemotherapy (CT). Incidence rate, temporal pattern, and potential risk factors associated with gastrointestinal perforation (GIP) were explored. Methods: Baseline patient characteristics (BC), including prospectively identified potential risk factors for GIP, were collected at study entry. Safety data were collected every 3 months (mo). Logistic regression models, adjusted and unadjusted for treatment assignment, were used to identify BC potentially associated with GIP. Results: 1968 pts were enrolled between Feb 2004 and Jun 2005. Median study follow-up was 10 mo as of Nov 4, 2005. GIPs were observed in 34 pts (1.7%). For pts with GIP, median time to first event was 2.1 mo; the majority of events were non-fatal and occurred within the first 3 mo after starting BV. BC including GI medical history (chronic aspirin or NSAID use, peptic ulcer disease, diverticulosis) were similar in pts with or without GIP and with earlier or later GIP onset (≤ or >3 mo from start of BV). Although adjusted models did not show any significant BC, GIP rates were numerically higher in pts with primary tumor intact (2.6%) vs. resected (1.6%). Furthermore, univariate analyses revealed a significant difference between intact (2.3%) and resected (0.8%) primary tumor for earlier GIP (≤3 mo from start of BV). The majority of pts with GIP had at least one of the following: acute diverticulitis, intra-abdominal abscess, gastrointestinal obstruction, tumor at GIP site, abdominal carcinomatosis, prior abdominal or pelvic radiation therapy. Conclusions: Preliminary analyses indicate the incidence of GIP in this large, community-based observational registry is similar to that previously reported in phase III mCRC trials with BV. No associations between specific BCs and an increased risk of GIP were identified. Patients with primary tumor intact were more likely to incur a GIP within the first 3 mo of starting BV and CT.

[Table: see text]