Global, multicenter, randomized, phase II trial of gemcitabine and gemcitabine plus AGS-1C4D4 in patients with previously untreated, metastatic pancreatic cancer

BACKGROUND

We evaluated AGS-1C4D4, a fully human monoclonal antibody to prostate stem cell antigen (PSCA), with gemcitabine in a randomized, phase II study of metastatic pancreatic cancer.

PATIENTS AND METHODS

Patients with Eastern Cooperative Oncology Group (ECOG) performance status 0/1 and previously untreated, metastatic pancreatic adenocarcinoma were randomly assigned 1:2 to gemcitabine (1000 mg/m(2) weekly seven times, 1 week rest, weekly three times q4weeks) or gemcitabine plus AGS-1C4D4 (48 mg/kg loading dose, then 24 mg/kg q3weeks IV). The primary end point was 6-month survival rate (SR). Archived tumor samples were collected for pre-planned analyses by PSCA expression.

RESULTS

Between April 2009 and May 2010, 196 patients were randomly assigned to gemcitabine (n = 63) or gemcitabine plus AGS-1C4D4 (n = 133). The 6-month SR was 44.4% (95% CI, 31.9-57.5) in the gemcitabine arm and 60.9% (95% CI, 52.1-69.2) in the gemcitabine plus AGS-1C4D4 arm (P = 0.03), while the median survival was 5.5 versus 7.6 months and the response rate was 13.1% versus 21.6% in the two arms, respectively. The 6-month SR was 57.1% in the gemcitabine arm versus 79.5% in the gemcitabine plus AGS-1C4D4 arm among the PSCA-positive subgroup and 31.6% versus 46.2% among the PSCA-negative subgroup.

CONCLUSIONS

This randomized, phase II study achieved its primary end point, demonstrating an improved 6-month SR with addition of AGS-1C4D4 to gemcitabine among patients with previously untreated, metastatic pancreatic adenocarcinoma. ClinicalTrials.gov identifier: NCT00902291.

Rationale and design of South Asian Birth Cohort (START): a Canada-India collaborative study

Background

People who originate from the Indian subcontinent (South Asians) suffer among the highest rates of type 2 diabetes in the world. Prior evidence suggests that metabolic risk factors develop early in life and are influenced by maternal and paternal behaviors, the intrauterine environment, and genetic factors. The South Asian Birth Cohort Study (START) will investigate the environmental and genetic basis of adiposity among 750 South Asian offspring recruited from highly divergent environments, namely, rural and urban India and urban Canada.

Methods

Detailed information on health behaviors including diet and physical activity, and blood samples for metabolic parameters and DNA are collected from pregnant women of South Asian ancestry who are free of significant chronic disease. They also undergo a provocative test to diagnose impaired glucose tolerance and gestational diabetes. At delivery, cord blood and newborn anthropometric indices (i.e. birth weight, length, head circumference and skin fold thickness) are collected. The mother and growing offspring are followed prospectively and information on the growth trajectory, adiposity and health behaviors will be collected annually up to age 3 years. Our aim is to recruit a minimum of 750 mother-infant pairs equally divided between three divergent environments: rural India, urban India, and Canada.

Summary

The START cohort will increase our understanding of the environmental and genetic determinants of adiposity and related metabolic abnormalities among South Asians living in India and Canada.

A calorimetric method to detect a weak or distributed latent heat contribution at first order magnetic transitions

Microcalorimetry has proven to be a versatile tool to investigate first order magnetic phase transitions as it can be used in different experimental modes to separate the latent heat from heat capacity. However, the methodology fails if the latent heat contribution is below instrumental resolution of 10 nJ. If the nucleation size of the new phase is much less than 100 μm, the typical size of the fragment measured, the latent heat could appear to be too distributed in temperature or magnetic field to be detected. Here, we show that for certain classes of magnetic transition, our microcalorimetry technique can be extended to enable an estimate of the latent heat to be obtained from a combination of heat capacity and magnetic measurements. This technique is best suited for material systems with weakly first order phase transitions, or highly distributed due to inhomogeneity.

Coexistence of universal and topological anomalous hall effects in metal CrO2 thin films in the dirty limit

The scaling exponent of 1.6 between anomalous Hall and longitudinal conductivity, characteristic of the universal Hall mechanism in dirty-metal ferromagnets, emerges from a series of CrO2 films as we systematically increase structural disorder. Magnetic disorder in CrO2 increases with temperature and this drives a separate topological Hall mechanism. We find that these terms are controlled discretely by structural and magnetic defect populations, and their coexistence leads to apparent divergence from exponent 1.6, suggesting that the universal term is more prevalent than previously realized.

A family-based intervention to promote healthy lifestyles in an aboriginal community in Canada

CONTEXT

Obesity is a major public health problem in North America, particularly in Aboriginal people.

OBJECTIVE

To determine if a household-based lifestyle intervention is effective at reducing energy intake and increasing physical activity among Aboriginal families after 6 months.

DESIGN, PARTICIPANTS, AND INTERVENTION

Randomized, open trial of 57 Aboriginal households recruited between May 2004 and April 2005 from the Six Nations Reserve in Ohsweken, Canada. Aboriginal Health Counsellors made regular home visits to assist families in setting dietary and physical activity goals. Additional interventions included provision of filtered water, a physical activity program for children, and educational events about healthy lifestyles.

RESULTS

57 households involving 174 individuals were randomized to intervention or usual care. Intervention households decreased consumption of fats, oils and sweets compared to usual care households (-4.9 servings per day vs. -3 servings/day, p=0.006), and this was associated with a reduction in trans fatty acids (-0.2 vs. +0.6 grams/day, p=0.02). Water consumption increased (+0.3 vs. -0.1 servings/day, p<0.04) and soda pop consumption decreased (-0.3 vs. -0.1 servings/day, p=0.02) in intervention households compared to usual care. A trend toward increased knowledge about healthy dietary practices in children, increased leisure-time activity and decreased sedentary behaviours was observed, although these differences were not statistically significant.

CONCLUSION

A household-based intervention is associated with some positive changes in dietary practices and activity patterns. A larger and longer-term intervention which addresses both individual change and structural barriers in the community is needed.

Serum levels of perfluoroalkyl compounds in human maternal and umbilical cord blood samples

Perfluoroalkyl compounds (PFCs) are end-stage metabolic products from industrial flourochemicals used in the manufacture of plastics, textiles, and electronics that are widely distributed in the environment. The objective of the present study was to quantify exposure to perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorodecanoic acid (PFDeA), perfluorohexane sulfonate (PFHxS), perfluoroheptanoic acid (PFHpA), and perfluorononanoic acid (PFNA) in serum samples collected from pregnant women and the umbilical cord at delivery. Pregnant women (n=101) presenting for second trimester ultrasound were recruited and PFC residue levels were quantified in maternal serum at 24-28 weeks of pregnancy, at delivery, and in umbilical cord blood (UCB; n=105) by liquid chromatography-mass spectrometry. Paired t-test and multiple regression analysis were performed to determine the relationship between the concentrations of each analyte at different sample collection time points. PFOA and PFOS were detectable in all serum samples analyzed including the UCB. PFOS serum levels (mean+/-S.D.) were significantly higher (p<0.001) in second trimester maternal serum (18.1+/-10.9 ng/mL) than maternal serum levels at delivery (16.2+/-10.4 ng/mL), which were higher than the levels found in UCB (7.3+/-5.8 ng/mL; p<0.001). PFHxS was quantifiable in 46/101 (45.5%) maternal and 21/105 (20%) UCB samples with a mean concentration of 4.05+/-12.3 and 5.05+/-12.9 ng/mL, respectively. There was no association between serum PFCs at any time point studied and birth weight. Taken together our data demonstrate that although there is widespread exposure to PFCs during development, these exposures do not affect birth weight.

Heat capacity and latent heat measurements of CoMnSi using a microcalorimeter

A new method of utilizing a commercial silicon nitride membrane calorimeter to measure the latent heat at a first order phase transition is presented. The method is a direct measurement of the thermoelectric voltage jump induced by the latent heat, in a thermally isolated system ideally suited for single crystal and small microgram samples. We show that when combined with the ac calorimetry technique previously developed, the resultant thermal measurement capabilities are extremely powerful. We demonstrate the applicability of the combined method with measurements on a 100 microm size fragment of CoMnSi exhibiting a sizable magnetocaloric effect near room temperature, and obtain good agreement with previously reported values on bulk samples.

A d.c. magnetic metamaterial

Electromagnetic metamaterials are a class of materials that have been artificially structured on a subwavelength scale. They are currently the focus of a great deal of interest because they allow access to previously unrealizable properties such as a negative refractive index. Most metamaterial designs have so far been based on resonant elements, such as split rings, and research has concentrated on microwave frequencies and above. Here, we present the first experimental realization of a non-resonant metamaterial designed to operate at zero frequency. Our samples are based on a recently proposed template for an anisotropic magnetic metamaterial consisting of an array of superconducting plates. Magnetometry experiments show a strong, adjustable diamagnetic response when a field is applied perpendicular to the plates. We have calculated the corresponding effective permeability, which agrees well with theoretical predictions. Applications for this metamaterial may include non-intrusive screening of weak d.c. magnetic fields.

Proximal loop jejunostomy is a useful adjunct in the management of multiple intestinal suture lines in the septic abdomen

Background

Bowel repair in the septic abdomen can be problematic. This study investigated the use of a proximal loop jejunostomy to protect injured or fistulated bowel that had been returned to the abdomen after repair and/or anastomosis.

Methods

Ten patients who underwent laparotomy for intra-abdominal sepsis and/or fistulation, followed by distal enteric repair and/or anastomosis and construction of a proximal defunctioning loop jejunostomy, were studied retrospectively. Seven patients had 21 intestinal suture lines returned to the peritoneal cavity in the presence of intra-abdominal sepsis (14 anastomoses, two enterotomy closures and five serotomy repairs). Two patients had a difficult relaparotomy for pelvic abscess (two distal anastomoses, one enterotomy closure and three serotomy repairs). The final patient had pelvic sepsis and radiation enteritis; the distal anastomosis was defunctioned by a loop jejunostomy.

Results

The median distance from the duodenojejunal flexure to the loop stoma was 80 (range 30–170) cm. All jejunostomies were closed via a local approach, a median of 11 (range 9–18) months after formation. There was no significant postoperative morbidity and no postoperative death. At a median follow-up of 7 (range 0·5–56) months eight patients had no requirement for nutritional support.

Conclusion

Use of a loop jejunostomy to protect suture lines in the septic abdomen justifies consideration of this procedure in selected patients.