Atezolizumab plus bevacizumab in non-clear cell renal cell carcinoma (NccRCC) and clear cell renal cell carcinoma with sarcomatoid differentiation (ccRCCsd): Updated results of activity and predictive biomarkers from a phase II study

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Background: NccRCC and ccRCCsd are aggressive tumors associated with poor prognosis and response to therapy. Combination strategies co-targeting VEGF signaling and inhibitory immune checkpoints are highly active in clear-cell renal cell carcinoma, but data is lacking in NccRCC and ccRCCsd. We conducted a multicenter, open-label, single arm phase II trial of atezolizumab plus bevacizumab in NccRCC and ccRCCsd. Methods: Patients with NccRCC and ccRCCsd ( > 20% sarcomatoid differentiation), and ECOG performance status of 0-2 were eligible. Prior systemic treatment was allowed with the exception of prior PD-1/PD-L1-directed therapy. Atezolizumab 1200mg and bevacizumab 15mg/kg were administered every 3 weeks until progression, unacceptable toxicity, or patient withdrawal. Primary endpoint was objective response rate (ORR) per RECIST 1.1. Exploratory biomarker analyses included PD-L1 expression on tumor (TC) and immune cells (IC), and spatial analysis of the immune infiltrate. Results: Sixty patients received at least 1 cycle of treatment, among whom 56 were evaluable for response (17 ccRCCsd and 39 NccRCC). ORR was 34% in the overall population, 53% in ccRCCsd and 26% in NccRCC. Median progression-free survival was 8.4 months (95%CI, 6.9-16.5). Baseline tumor tissue was available for 36 patients. TC PD-L1 expression ≥1% was associated with improved ORR (9/14, 64%) compared to patients with PD-L1 expression < 1% (4/20, 20%). Patients with TC PD-L1 expression ≥1% who experienced progressive disease as best response had shorter average distance between tumor cells and nearest neighboring immune cells at baseline. Further analysis of the immune tumor microenvironment on an expanded cohort, including IC PD-L1 expression and correlation with clinical outcomes, is ongoing and will be updated. Conclusions: The combination of atezolizumab plus bevacizumab is active in NccRCC and ccRCCsd. Candidate predictive biomarkers include PD-L1 expression in TC and topological analysis of the immune infiltrate. Clinical trial information: NCT02724878.

Results of a phase II study of atezolizumab and bevacizumab in non-clear cell renal cell carcinoma (nccRCC) and clear cell renal cell carcinoma with sarcomatoid differentiation (sccRCC)

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Background: NccRCC and sccRCC have historically been underrepresented in clinical trials. Even with targeted therapy, most patients have inferior survival compared to clear cell renal cell carcinoma. The combination of atezolizumab and bevacizumab has demonstrated safety and efficacy in ccRCC. In this multicenter, phase II, open-label, single arm trial we evaluate the efficacy of atezolizumab and bevacizumab in patients with nccRCC and sccRCC with >20% sarcomatoid differentiation. Methods: Eligible patients had an ECOG performance status of 0-2 and may have received prior therapy. Prior PD-1/PD-L1 therapy was not allowed. Patients underwent a mandatory baseline biopsy and subsequently received atezolizumab 120 mg and bevacizumab 15 mg/kg intravenously every 3 weeks. Patients remained on therapy until radiographic progression, unacceptable adverse events, or withdrawal. The primary end point was overall response rate (ORR) as determined by RECIST version 1.1. Results: 65 patients were enrolled of whom 52 had ≥1 response assessment and were included in this analysis. 36 patients had nccRCC (papillary n=14, chromophobe n=8, unclassified RCC n=3, collecting duct n=3, translocation n=3, other n=5), and 16 patients had sccRCC. 17 patients received prior systemic therapy, 16 of whom had nccRCC. The ORR was 31% in the overall cohort (Table 1). 10 patients (19%) developed grade 3 treatment-related adverse events (AEs), half of which were immune-related. There were no grade 4-5 AEs. Conclusions: In this study, we show that therapy with atezolizumab and bevacizumab was safe and demonstrated anti-tumor activity in nccRCC and sccRCC. Further analyses will report ORR by histologic subtype and PD-L1 expression status. Analysis of tissue and blood-based biomarkers of response are ongoing. Clinical trial information: NCT02724878. [Table: see text]

Cabozantinib versus sunitinib for previously untreated patients with advanced renal cell carcinoma (RCC) of intermediate or poor risk: Subgroup analysis of progression-free survival (PFS) and objective response rate (ORR) in the Alliance A031203 CABOSUN trial

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Background: The randomized phase 2 CABOSUN trial (NCT01835158) compared cabozantinib (C) with sunitinib (S) as initial systemic therapy in patients (pts) with RCC of intermediate or poor risk. Compared with S, C improved both PFS and ORR as assessed by independent radiology review committee (IRC). Median PFS per IRC was 8.6 mo for C vs 5.3 mo for S (HR 0.48, 95% CI 0.31-0.74 two-sided p = 0.0008), and ORR per IRC was 20% vs 9%. Methods: 157 patients were randomized 1:1 to receive C (60 mg qd) or S (50 mg qd, 4 weeks on/2 weeks off) stratified by International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk group and the presence of bone metastases. Subgroup analyses of PFS per IRC and ORR per IRC are presented based on stratification factors, age, sex, baseline ECOG status, and MET tumor expression by immunohistochemistry. The primary endpoint was investigator-assessed PFS. PFS and ORR were evaluated by IRC in a post-hoc analysis. Results: 45% of pts were ≥65 years, 78% were male, 54% were ECOG 1 or 2, 19% were poor risk, and 36% had bone metastases. MET status was determined in 131 pts; of these 47% were MET positive. The HR for PFS per IRC favored C over S across all subgroups analyzed (Table). Subgroups with poor prognostic characteristics (poor risk, ECOG 1 or 2, presence of bone metastases) had shorter median PFS for both C and S. Odds ratios for ORR also favored C over S, with the highest C ORR in the MET positive subgroup (34% C vs 10% S). Conclusions: C was associated with improved PFS and ORR compared with S in previously untreated pts with advanced RCC irrespective of baseline characteristics. Clinical trial information: NCT01835158. [Table: see text]

A video-based, personalized web page (VBPWP) as a complement to clinical trial (CT) patient management

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Background: Most advances in the diagnosis and treatment (Tx) of patients (pts) with genitourinary (GU) cancers are the result of pt involvement in CTs. There is a clear need to identify ways to improve CT processes for pts and research teams (RTs). The goal of this project is to assess the use of a VBPWP to improve pt compliance, safety, CT quality, and RT efficiency in GU CTs of oral agents. Methods: This is an unblinded, randomized trial using a VBPWP as an intervention (INT) for pts with advanced non-metastatic (M0) or metastatic (M1) GU cancers. Pts consented but not yet started on CTs of oral agents are randomized 2:1 to the INT or control arm. The INT includes videos of provider-pt encounters and educational videos related to dosing and adverse events (AEs). Target accrual is 99 pts. The primary end point is number of cumulative pt violations (PVs) over 4 cycles (4Cs) of INT. PVs are defined as improper dosing, non-compliance, and failure to report AEs or hospitalizations. Herein we report an early pooled analysis of pts who completed 4Cs. Results: 90 pts enrolled (61 M1, 67 prostate, 22 kidney). 58 pts completed ≥ 4Cs. 58% (n = 33) of pts had ≥ 1 PV on study (Table). Despite RT instructions, overall, 7%, 9%, and 3% of pts failed to return pill bottles or report AEs, missed a dose of Tx on 3 occasions, or took a wrong dose, respectively. Median total score of the Functional Assessment of Chronic Illness Therapy Tx Satisfaction-Pt Satisfaction (FACIT-TS-PS) measure was 72 (n = 45) at baseline (BL) and did not significantly change after 4Cs (73, n = 48). Scores of 73 indicate high levels of pt satisfaction. The Perceived Stress Scale (PSS) 10-Item indicated pt stress levels were highest at BL (score = 28) and improved after 1C of Tx (score = 24). Scores ≥ 20 indicate high stress. Stress levels did not significantly change after 4Cs. Conclusions: Longer follow up is needed to compare outcomes between pts randomized to the video INT compared to the control arm. Data show that the majority had ≥ 1 PV. This suggests the need to improve education for CT pts. The use of a VBPWP as a complement to standard CT pt education is feasible and may have the potential to increase pt safety and CT quality. [Table: see text]

Outcomes of PD-1/PD-L1 responders who discontinue therapy for immune-related adverse events (irAEs): Results of a cohort of patients (pts) with metastatic renal cell carcinoma (mRCC)

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Background: Nivolumab, a monoclonal antibody against PD-1, has been shown to improve survival for pts with mRCC. The current standard of care is to administer treatment on a continuous basis until progression or toxicity. Outcomes of pts who experience a response to treatment and then discontinue therapy for irAEs have not been fully characterized. The purpose of this analysis was to evaluate outcomes of responders to PD-1/PD-L1 targeted therapy (TT) who discontinue treatment for irAEs. Methods: We identified pts with mRCC having experienced a response to PD-1/PD-L1 TT, which was subsequently discontinued for an irAE. Clinical characteristics, response, and survival data were collected. Results: We identified 9 mRCC pts who were treated with a PD-1/PD-L1 inhibitor, experienced a response to therapy, and subsequently discontinued treatment for an irAE. 8 had clear cell histology and 1 had translocation RCC. 7 pts were treatment naive. 2 pts had International mRCC Database Consortium favorable risk, 4 intermediate risk, and 3 poor risk disease. 44% (n = 4) of pts received PD-1/PD-L1 monotherapy and the overall median duration of therapy was 5 months (mos) (range 4-15). There was 1 complete response, 7 partial responses, and 1 stable disease (17% shrinkage). Treatment was discontinued for the following irAEs: arthritis, uveitis, arthropathy, hypophysitis, myositis, blepharitis, hepatitis, rash, pericarditis, and amylase and lipase elevations. After PD-1/PD-L1 treatment discontinuation, 4 (44%) pts remained progression free with a median time off therapy of 20 mos (range 10-44) and median time on therapy of 9 mos (range 4-15). 5 (56%) pts progressed within 6 mos (range 2-6) of treatment discontinuation and median time on therapy was 4 mos (range 3-10). Conclusions: We demonstrate that some pts can have persistent clinical benefit after discontinuation of PD-1/PD-L1 TT for irAEs. Larger studies are warranted to evaluate the need for continuous drug dosing in all pts, identify pts in which continuous dosing is not required, and evaluate long-term outcomes in this population.

Cabozantinib Versus Sunitinib As Initial Targeted Therapy for Patients With Metastatic Renal Cell Carcinoma of Poor or Intermediate Risk: The Alliance A031203 CABOSUN Trial

Purpose Cabozantinib is an oral potent inhibitor of vascular endothelial growth factor receptor 2, MET, and AXL and is a standard second-line therapy for metastatic renal cell carcinoma (mRCC). This randomized phase II multicenter trial evaluated cabozantinib compared with sunitinib as first-line therapy in patients with mRCC. Patients and Methods Eligible patients had untreated clear cell mRCC and Eastern Cooperative Oncology Group performance status of 0 to 2 and were intermediate or poor risk per International Metastatic Renal Cell Carcinoma Database Consortium criteria. Patients were randomly assigned at a one-to-one ratio to cabozantinib (60 mg once per day) or sunitinib (50 mg once per day; 4 weeks on, 2 weeks off). Progression-free survival (PFS) was the primary end point. Objective response rate (ORR), overall survival, and safety were secondary end points. Results From July 2013 to April 2015, 157 patients were randomly assigned (cabozantinib, n = 79; sunitinib, n = 78). Compared with sunitinib, cabozantinib treatment significantly increased median PFS (8.2 v 5.6 months) and was associated with a 34% reduction in rate of progression or death (adjusted hazard ratio, 0.66; 95% CI, 0.46 to 0.95; one-sided P = .012). ORR was 33% (95% CI, 23 to 44) for cabozantinib versus 12% (95% CI, 5.4 to 21) for sunitinib. All-causality grade 3 or 4 adverse events were 67% for cabozantinib and 68% for sunitinib and included diarrhea (cabozantinib, 10% v sunitinib, 11%), fatigue (6% v 15%), hypertension (28% v 22%), palmar-plantar erythrodysesthesia (8% v 4%), and hematologic adverse events (3% v 22%). Conclusion Cabozantinib demonstrated a significant clinical benefit in PFS and ORR over standard-of-care sunitinib as first-line therapy in patients with intermediate- or poor-risk mRCC.

A phase Ib dose-escalation study of TRC105 (anti-endoglin antibody) in combination with axitinib in patients with metastatic renal cell carcinoma

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Background: Resistance to VEGF-targeted therapy is a major challenge in contemporary treatment of metastatic renal cell carcinoma (mRCC), and endoglin (CD105) activation may be an important mechanism leading to resistance. Endoglin is an essential angiogenic receptor expressed on proliferating tumor vessels and mRCC cancer stem cells that is upregulated following VEGF inhibition. TRC105 is an anti-endoglin monoclonal antibody that potentiates bevacizumab (Bev) and VEGF receptor tyrosine kinase inhibitors (VEGFR TKI) in preclinical models. Methods: Heavily-pretreated mRCC pts with ECOG PS 0-1, and acceptable organ function were treated with TRC105 weekly (8 mg/kg and then 10 mg/kg) in combination with axitinib (initially at 5 mg PO BID and then escalated per patient tolerance to a maximum of 10 mg PO BID). Results: Eighteen mRCC pts (median age=61.5; M:F 16:2; median number of prior therapies=3, including >1 VEGFR TKI, clear cell=13, prior axitinib allowed) were treated. TRC105 dose escalation proceeded from 8 mg/kg (n=3) to 10 mg/kg (n=15) without dose limiting toxicity. Low grade AEs characteristic of each drug were not increased in frequency or severity at the recommended phase 2 doses of the two drugs. Three pts (18%) were PR by RECIST and 8 of 17 pts (47%) exhibited >10% tumor reduction. Median PFS is not mature and is at least 5.8 months in the overall population and at least 5.9 months in ccRCC pts. The single patient who progressed on axitinib immediately prior to study entry remains progression free at month 5 with minor tumor regression. Conclusions: TRC105 at 8 and 10 mg/kg was well tolerated with axitinib in mRCC pts with signs of activity. A multicenter randomized phase II trial of axitinib +/- TRC105 is accruing at this time. Clinical trial information: NCT01806064.

A phase II multicenter study of neoadjuvant dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (ddMVAC) chemotherapy with pegfilgrastim support in patients (pts) muscle-invasive urothelial cancer (MIUC): Safety, pathologic, radiologic, and molecular correlates

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Background: ddMVAC is associated with high responses rate (RR) in advanced urothelial cancer (UC). We embarked on a study in MIUC to determine pathologic RR and its correlation with clinical and radiological outcomes as well as DNA excision repair pathway biomarkers (ERCC1, PAR, BRCA1, and BRCA2). Methods: Patients with cT2-T4, N0-1, M0 UC, and adequate kidney and marrow function were enrolled on a prospective multicenter phase II trial. Four cycles of ddMVAC were given followed by radical cystectomy (RC). The primary endpoint was pathologic downstaging to <pT1N0M0. The treatment would be considered effective if 17 of 37 eligible patients (46%) met the primary endpoint (85% power, 1-sided type I error 0.1). Secondary endpoints included safety, imaging response (by contrast-enhanced imaging, largely MRI), and biomarker correlates. Results: Between 12/08 and 4/12, 39 pts (cT2:42%; cT3:42%, cT4:16%, N1:45%) were enrolled. 91% had bladder primary, and 95% received 4 cycles of ddMVAC. Median follow up was 18 months. One patient developed distant metastases before RC. Of 39 eligible pts, 49% (90% CI 35-63) downstaged to <pT1N0M0 (pT0N0=26%), and the primary endpoint was met. 14/17 (82%) of pts with cN1 disease had pN0 at surgery; no pts with cN0 was found to have pN(+). Toxicities >Grade 3 related to chemotherapy were observed in 10% of pts and included mucositis, hand-foot skin reaction, hypokalemia and neutropenia. No neutropenic fevers were seen. Median and 18-month disease-free survival (DFS) is provided in Table. Tissue biomarker analyses will be presented. Conclusions: ddMVAC regimen is well tolerated and results in significant pathologic and radiologic downstaging in pts with MIUC. Clinical trial information: NCT00808639. [Table: see text]

DAYCENT national-scale simulations of nitrous oxide emissions from cropped soils in the United States

Until recently, Intergovernmental Panel on Climate Change (IPCC) emission factor methodology, based on simple empirical relationships, has been used to estimate carbon (C) and nitrogen (N) fluxes for regional and national inventories. However, the 2005 USEPA greenhouse gas inventory includes estimates of N2O emissions from cultivated soils derived from simulations using DAYCENT, a process-based biogeochemical model. DAYCENT simulated major U.S. crops at county-level resolution and IPCC emission factor methodology was used to estimate emissions for the approximately 14% of cropped land not simulated by DAYCENT. The methodology used to combine DAYCENT simulations and IPCC methodology to estimate direct and indirect N2O emissions is described in detail. Nitrous oxide emissions from simulations of presettlement native vegetation were subtracted from cropped soil N2O to isolate anthropogenic emissions. Meteorological data required to drive DAYCENT were acquired from DAYMET, an algorithm that uses weather station data and accounts for topography to predict daily temperature and precipitation at 1-km2 resolution. Soils data were acquired from the State Soil Geographic Database (STATSGO). Weather data and dominant soil texture class that lie closest to the geographical center of the largest cluster of cropped land in each county were used to drive DAYCENT. Land management information was implemented at the agricultural-economic region level, as defined by the Agricultural Sector Model. Maps of model-simulated county-level crop yields were compared with yields estimated by the USDA for quality control. Combining results from DAYCENT simulations of major crops and IPCC methodology for remaining cropland yielded estimates of approximately 109 and approximately 70 Tg CO2 equivalents for direct and indirect, respectively, mean annual anthropogenic N2O emissions for 1990-2003.

Performance of Dairy Cattle Clones and Evaluation of Their Milk Composition

Genetic and phenotypic performance of U.S. Holstein embryo-split and nuclear-transfer clones was documented for yield and fitness traits. For cows, mean genetic superiority based on pedigree was 186 kg of milk, 9 kg of fat, and 7 kg of protein for embryo-split clones and 165, 10, and 8 kg, respectively, for nuclear-transfer clones compared with the population for the same birth year; pedigree advantage for male clones generally was slightly greater. Estimates of genetic merit that considered a clone's own performance as well as pedigree merit were slightly lower for embryo-split cows than for their full siblings for yield but not for milk composition (fat and protein percentages), mastitis resistance (somatic cell score), longevity (productive life), or cow fertility (daughter pregnancy rate); no corresponding genetic differences were found for nuclear-transfer cows or for cloned bulls regardless of clone type. For bulls, estimated genetic merit based on daughter yield was more similar for clone pairs with apparent identical genotype than for pairs from the same biotechnology but nonidentical as confirmed by blood typing. Yield deviations were lower for clones than for their full siblings. Milk composition (total solids, fat, fatty acid profile, lactose, and protein) also was compared for nuclear-transfer clones (Brown Swiss, Holstein, and Holstein-Jersey cross) with non-cloned cows and literature values; no differences were found for gross chemical composition of milk. No obvious differences were evident between cloned and non-cloned animals or for the milk that they produced.

Risk-adjusted capitation funding models for chronic disease in Australia: alternatives to casemix funding

Under Australian casemix funding arrangements that use Diagnosis-Related Groups (DRGs) the average price is policy based, not benchmarked. Cost weights are too low for State-wide chronic disease services. Risk-adjusted Capitation Funding Models (RACFM) are feasible alternatives. A RACFM was developed for public patients with cystic fibrosis treated by an Australian Health Maintenance Organization (AHMO). Adverse selection is of limited concern since patients pay solidarity contributions via Medicare levy with no premium contributions to the AHMO. Sponsors paying premium subsidies are the State of Victoria and the Federal Government. Cost per patient is the dependent variable in the multiple regression. Data on DRG 173 (cystic fibrosis) patients were assessed for heteroskedasticity, multicollinearity, structural stability and functional form. Stepwise linear regression excluded non-significant variables. Significant variables were 'emergency' (1276.9), 'outlier' (6377.1), 'complexity' (3043.5), 'procedures' (317.4) and the constant (4492.7) (R(2)=0.21, SE=3598.3, F=14.39, Prob<0.0001. Regression coefficients represent the additional per patient costs summed to the base payment (constant). The model explained 21% of the variance in cost per patient. The payment rate is adjusted by a best practice annual admission rate per patient. The model is a blended RACFM for in-patient, out-patient, Hospital In The Home, Fee-For-Service Federal payments for drugs and medical services; lump sum lung transplant payments and risk sharing through cost (loss) outlier payments. State and Federally funded home and palliative services are 'carved out'. The model, which has national application via Coordinated Care Trials and by Australian States for RACFMs may be instructive for Germany, which plans to use Australian DRGs for casemix funding. The capitation alternative for chronic disease can improve equity, allocative efficiency and distributional justice. The use of Diagnostic Cost Groups (DCGs) is a promising alternative classification system for capitation arrangements.

Solitary blood cultures: a College of American Pathologists Q-probes study of 132,778 blood culture sets in 333 small hospitals

OBJECTIVE

To determine the frequency with which solitary blood culture samples were submitted to laboratories serving small hospitals and to ascertain whether certain hospital practices relating to the performance of blood cultures were associated with lower solitary blood culture rates (SBCRs).

DESIGN

Participants in the College of American Pathologists Q-Probes laboratory quality improvement program collected data prospectively on the numbers of solitary blood culture sets from adult patients submitted to their laboratories and answered questions about their institutions' practice characteristics relating to the collection of blood culture specimens.

SETTING AND PARTICIPANTS

Three hundred thirty-three public and private institutions with a median occupied bed size of 57. Participants were located in the United States (n = 329), Canada (n = 3), and Australia (n = 1).

MAIN OUTCOME MEASURE

The solitary blood culture rate was defined as the number of instances in which only 1 blood culture venipuncture was performed on an individual patient during a 24-hour period divided by the total number of blood culture venipunctures that were performed during the study period.

RESULTS

Participants submitted data on 132 778 adult patient blood culture sets. The SBCRs were 3.4% or less in the top-performing 10% of participating institutions (90th percentile and above), 12.7% in the midrange of participating institutions (50th percentile), and 42.5% or more in the bottom-performing 10% of participating institutions (10th percentile and below). In half the participating institutions, the SBCRs for inpatients were 8.3% or less and for outpatients, 22% or less. Solitary blood culture rates were lower for institutions in which phlebotomists rather than nonphlebotomists routinely collected blood culture specimens, in which internal policies required drawing at least 2 blood culture sets, in which hospital personnel contacted clinicians when their laboratories received requests for solitary blood culture sets, and in which quality control programs monitored SBCRs routinely.

CONCLUSIONS

Hospitals can achieve SBCRs under 5%. Those hospitals with particularly high SBCRs may lower their rates by altering certain institutional practices.

Asynchronous synapse elimination in neonatal motor units: studies using GFP transgenic mice

In developing muscle, synapse elimination reduces the number of motor axons that innervate each postsynaptic cell. This loss of connections is thought to be a consequence of axon branch trimming. However, branch retraction has not been observed directly, and many questions remain, such as: do all motor axons retract branches, are eliminated branches withdrawn synchronously, and are withdrawing branches localized to particular regions? To address these questions, we used transgenic mice that express fluorescent proteins in small subsets of motor axons, providing a unique opportunity to reconstruct complete axonal arbors and identify all the postsynaptic targets. We found that, during early postnatal development, each motor axon loses terminal branches, but retracting branches withdraw asynchronously and without obvious spatial bias, suggesting that local interactions at each neuromuscular junction regulate synapse elimination.

Affinity enrichment of bovine lactoferrin in whey

Bovine lactoferrin was enriched in various whey samples by affinity chromatography using immobilized gangliosides. Bovine gangliosides were isolated from fresh buttermilk using a combination of ultrafiltration and organic extraction. Isolated gangliosides were covalently immobilized onto controlled-pore glass beads. The immobilized matrix contained 66 micrograms of gangliosides per gram of beads. After loading the matrix with reconstituted whey protein isolate (WPI) or whey protein concentrate (WPC), the matrix was washed with sodium phosphate buffer (pH 7) followed by sodium acetate buffer (pH 4) before elution of lactoferrin with 1 M NaCl in sodium acetate buffer. From the intensities of the protein bands in SDS-PAGE, lactoferrin constituted a minimum of 40% of the total protein in the salt eluted sample. WPI, pretrated by heating and ultrafiltration, showed the highest lactoferrin purity among protein sources, while WPI (10% wt/vol) showed the highest recovery. These results show that immobilized gangliosides can be used to enrich the lactoferrin content of whey.

Rapid fractionation of bovine transferrin using immobilized gangliosides

Bovine transferrin (BTF) was fractionated from bovine whey using ganglioside affinity chromatography. After loading the immobilized matrix with a 2% whey solution, the matrix was washed with sodium acetate buffer at pH 4 containing 1 M NaCl before elution of BTF with sodium phosphate buffers at pH 7. Concanavalin-A affinity and ion exchange chromatography were used for further purification. The ganglioside column showed a 74.2% BTF recovery from whey and BTF was enriched to 61% purity with ion exchange chromatography. Bovine transferrin was identified by SDS-PAGE and western analysis. The Concanavalin-A affinity and ion exchange chromatography steps enriched BTF in the samples and removed other whey proteins from ganglioside purified fractions. These results indicate that immobilized ganglioside can be used to fractionate BTF from bovine whey. Our novel ganglioside affinity chromatography is rapid and efficient for the fractionation of BTF from whey.

Solid-phase capture of proteins, spores, and bacteria

Current methods for the detection of pathogens in food and water samples generally require a preenrichment step that allows selective enrichment of the test organism. The objective of this research was to eliminate an enrichment step to allow detection of bacteria directly in food and water samples in 30 min. A high-flow-rate, fluidized bed to capture and concentrate large (bacteria and spores) and small (protein) molecules was developed. This format, ImmunoFlow, is volume independent and uses large beads (greater than 3 mm in diameter) when capturing bacteria to prevent sample clogging when testing food samples. Detection of bound targets was done using existing enzyme-linked immunosorbent assay (ELISA) protocols. Four antibodies (anti-Escherichia coli O157:H7, -Bacillus globigii, -bovine serum albumin [BSA], and -ovalbumin [OVA]) were covalently coupled to various glass and ceramic beads. Very small amounts of BSA (<1 ng) and OVA (0.2 to 4.0 microg) were detected. Various industrial and environmental samples were used to observe the effect of the sample composition on the capture of anti-B. globigii and anti-E. coli O157:H7 modified beads. The lower limit of detection for both E. coli O157:H7 and B. globigii was 1 spore/cell independent of the sample size. The activity of anti-B. globigii modified beads declined after 3 days. Anti-E. coli O157:H7 modified beads declined in their capture ability after 2 days in various storage buffers. Storage temperature (4 and 25 degrees C) did not influence the stability. The ImmunoFlow technology is capable of capturing bacteria and spores directly from samples, with subsequent detection in an ELISA format in 30 min.

Optimizing the immobilization of single-stranded DNA onto glass beads

The attachment of single-stranded DNA to a solid support has many biotechnology and molecular biology applications. This paper compares different immobilization chemistries to covalently link single-stranded DNA (20 base pairs), oligo(1), onto glass beads via a 5'-amino terminal end. Immobilization methods included a one-step 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and a two-step EDC reaction to succinylated and PEG-modified glass beads. The third method used 1,4-phenylene diisothiocyanate to immobilize oligo(1) to aminopropyl glass beads. The influence of coupling buffer, oligo(1) concentration, and EDC concentration was also investigated. The one-step EDC-mediated procedure with succinylated or PEG-modified beads in 0.1 M MES buffer, pH 4.5, resulted in the highest immobilization efficiency, 82-89%. EDC concentrations greater than 50 mM and oligo(1) concentrations of 3 microg/g bead were required for effective immobilization. A complementary oligonucleotide, oligo(2), was able to hybridize to the immobilized oligo(1) with a 58% efficiency. This oligonucleotide was subsequently released at 70 degrees C. The relationship between the surface density of oligo(1) and the hybridization efficiency of the complementary oligonucleotide is described.

Interinstitutional variation in glycohemoglobin monitoring and glycemic control of diabetic patients

OBJECTIVES

To compare how frequently institutions monitor glycohemoglobin in diabetic patients, the level of glycemic control achieved and to identify institutional factors associated with higher rates of monitoring and lower glycohemoglobin levels.

METHODS

A total of 212 institutions retrospectively abstracted laboratory and outpatient records of up to 30 diabetic patients who had initial glycohemoglobin monitoring performed in their laboratories. Data from a cohort of 5586 diabetic patients and 17 365 assays were analyzed.

RESULTS

Overall, 31.3% of patients underwent glycohemoglobin monitoring at least quarterly, the frequency recommended by the American Diabetes Association (ADA) to stabilize patients at target hemoglobin A(1c) (HbA(1c)) levels. A total of 64.9% of patients were monitored at least semiannually, the ADA recommendation for patients with stable diabetes in glycemic control (final HbA(1c) level <7%). When we compared the top and bottom deciles of the 212 institutions, there was more than an eightfold difference in the proportion of patients monitored at least quarterly and more than a twofold difference in the proportion of patients monitored at least semiannually. Glycemic control was assessed by examining the value of the last glycohemoglobin determination on record after at least 8 months of management. For all 5586 diabetic patients, the median value of the last HbA(1c) assay was 7.4%. Comparing the top and bottom deciles, there was almost a fourfold difference among institutions in the proportion of diabetic patients in glycemic control. The use of reminders to order glycohemoglobin monitoring was associated with higher rates of semiannual monitoring (P <.05) and tighter glycemic control (P <.05). In addition, patients who were monitored more frequently experienced glycohemoglobin reductions of greater magnitude (P <.001). The presence of diabetes clinics and the use of rapid methods for testing glycohemoglobin were not associated with monitoring frequency or glycohemoglobin levels.

CONCLUSIONS

There is wide interinstitutional variation in the frequency with which diabetic patients are monitored and the level of glycemic control achieved. The use of prompting systems to remind providers to order glycohemoglobin monitoring was associated with more frequent monitoring and superior glycemic control.

Thermal stability of acid proteinases

Milk-clotting enzymes are used during the production of cheese to coagulate the casein, allowing the formation of a three-dimensional network that entraps the milk fat. Commercially available milk-clotting enzymes differ with respect to source, specificity, optimum pH and thermostability. All are acid proteinases that can cleave κ-casein resulting in the coagulation of milk. Chymosin (EC 3.4.23.4) is specific for the Phe–Met bond in κ-casein at the natural pH of milk (6·7). Recombinant chymosin is available commercially from a variety of sources and has a maximum activity at 40 °C. Recombinant chymosins are purified from the fermentation of recombinant strains of Aspergillus niger, Asp. oryzae or Kluyveromyces marxianus. These enzyme preparations are chemically and functionally identical to calf chymosin. Rennets are purified from the abomasum of bovines and can contain from 60 to 100% chymosin with the remainder being primarily bovine pepsin (Wigley, 1996). Microbial proteinases (EC 3.4.23.6) are generally more proteolytic than chymosin, with varying heat stability. These enzymes liberate more non-protein N from casein and can cleave α- and β-casein as well as κ-casein at the natural pH of milk. Acid proteinases from Cryphonectria parasitica are more heat labile than those from Rhizomucor miehei, which are characterized as thermostable (Ernstrom & Wong, 1974).

The objective of this research was to characterize milk-clotting enzymes with respect to thermal inactivation in skim milk. This information has applications in milk and whey processing.

Influence of a poly-ethylene glycol spacer on antigen capture by immobilized antibodies

The use of spacers to distance an immobilized antibody from the surface of a support matrix introduces flexibility, which can reduce steric interferences between antibodies leading to a higher antigen capture efficiency. In this paper we investigated the use of a spacer molecule, poly-ethylene glycol (PEG), between the matrix surface and antibodies for the capture of Bacillus globigii, E. coli O157:H7, and ovalbumin. The antigen capture efficiency was determined using a surface ELISA method. Antibodies against the antigens were covalently immobilized either directly or via PEG to glass surfaces using a one-step EDC reaction. The amount of antibody immobilized was determined before blocking the nonspecific binding sites with bovine serum albumin. Antibodies immobilized via a PEG spacer showed a higher capture efficiency compared to direct immobilization, which was more pronounced with large antigens. Antibodies immobilized on glass supports were stable at 65 degrees C for at least 80 min, and the capture efficiency increased with heating at 65 degrees C for 20 min.

Use of amino acid analysis for estimating the individual concentrations of proteins in mixtures

The concentrations of five individual proteins in a mixture were determined from one amino acid analysis of the mixture by solving for each protein using simultaneous equations. Dried casein and whey were separated into five individual protein components using reversed-phase HPLC. Individual proteins were collected and analyzed for amino acid composition. These data were used as standards. Mixtures of purified proteins were analyzed for total amino acid composition and the concentrations of individual proteins in the mixtures were determined by solving simultaneous equations based on the amino acid analysis composition of the standards.

Characterization and expression of the pseudomonas putida bacterioferritin alpha subunit gene

The root-colonizing pseudomonad Pseudomonas putida (Pp) appears to produce two subunits, alpha and beta, of the iron-binding protein, bacterioferritin. A gene encoding the alpha-bacterioferritin subunit was located adjacent to the major catalase in Pp. The deduced protein sequence of the Pp bfralpha gene had a very high identity with other alpha-subunits, possessing conserved amino acids responsible for ferroxidase activity. The gene also lacked a deduced methionine at residue 52, associated with heme binding in beta-subunits. An antibody generated toward the Escherichia coli (E. coli) multifunctional single subunit bacterioferritin recognized two proteins in the Pp extract, a 22 kDa protein likely to be a beta-subunit and, to a lesser extent, a 23 kDa band. The 23 kDa band was absent in a Pp mutant in which the bfralpha gene was disrupted. Loss of alpha-bacterioferritin stimulated production of fluorescent siderophore. Growth on media and on root surfaces was not impaired by deletion of the alpha-bacterioferritin. Transcription of bfralpha was independent of the catalase gene and was dependent on iron. The transcript levels from bfralpha decreased in iron deficiency experienced during stationary-phase or upon treatment during growth with an iron chelator.

Forecasting hospital expenditure in Victoria: lessons from Europe and Canada

This paper specifies an econometric model to forecast State government expenditure on recognised public hospitals in Victoria. The OECD's recent cross-country econometric work exploring factors affecting health spending was instructive. The model found that Victorian Gross State Product, population aged under 4 years, the mix of public and private patients in public hospitals, introduction of casemix funding and funding cuts, the proportion of public beds to total beds in Victoria and technology significantly impacted on expenditure. The model may have application internationally for forecasting health costs, particularly in short and medium-term budgetary cycles.

Fostering progress and development (in an anaesthetic department) at a time of cost containment

The lessons learned in industry can be applied to anaesthetic departments. Progress and development are part of improving quality, and evidence is emerging that improved quality can reduce costs. Improving quality requires anaesthetic departments to develop a clear customer focus. Education, training, research and quality improvement are essential components of a quality anaesthetic department. Some of the cost reductions are achieved by development of partnerships with customers and suppliers. The emphasis is likely to shift from cost reduction to quality improvement and anaesthetic departments should anticipate this change.

A new ambulatory classification and funding model for radiation oncology: non-admitted patients in Victorian hospitals

The Victorian Department of Human Services has developed a classification and funding model for non-admitted radiation oncology patients. Agencies were previously funded on an historical cost input basis. For 1996-97, payments were made according to the new Non-admitted Radiation Oncology Classification System and include four key components. Fixed grants are based on Weighted Radiation Therapy Services targets for megavoltage courses, planning procedures (dosimetry and simulation) and consultations. The additional throughput pool covers additional Weighted Radiation Therapy Services once targets are reached, with access conditional on the utilisation of a minimum number of megavoltage fields by each hospital. Block grants cover specialised treatments, such as brachytherapy, allied health payments and other support services. Compensation grants were available to bring payments up to the level of the previous year. There is potential to provide incentives to promote best practice in Australia through linking appropriate practice to funding models. Key Australian and international developments should be monitored, including economic evaluation studies, classification and funding models, and the deliberations of the American College of Radiology, the American Society for Therapeutic Radiology and Oncology, the Trans-Tasman Radiation Oncology Group and the Council of Oncology Societies of Australia. National impact on clinical practice guidelines in Australia can be achieved through the Quality of Care and Health Outcomes Committee of the National Health and Medical Research Council.

Fish consumption and the 30-year risk of fatal myocardial infarction

BACKGROUND

Epidemiologic data on the possible benefit of eating fish to reduce the risk of coronary heart disease have been inconsistent. We used data from the Chicago Western Electric Study to examine the relation between base-line fish consumption and the 30-year risk of death from coronary heart disease.

METHODS

The study participants were 1822 men who were 40 to 55 years old and free of cardiovascular disease at base line. Fish consumption, as determined from a detailed dietary history, was stratified (0, 1 to 17, 18 to 34, and > or = 35 g per day). Mortality from coronary heart disease, ascertained from death certificates, was classified as death from myocardial infarction (sudden or nonsudden) or death from other coronary causes.

RESULTS

During 47,153 person-years of follow-up, there were 430 deaths from coronary heart disease; 293 were due to myocardial infarctions (196 were sudden, 94 were nonsudden, and 3 were not classifiable). Cox proportional-hazards regression showed that for men who consumed 35 g or more of fish daily as compared with those who consumed none, the relative risks of death from coronary heart disease and from sudden or nonsudden myocardial infarction were 0.62 (95 percent confidence interval, 0.40 to 0.94) and 0.56 (95 percent confidence interval, 0.33 to 0.93), respectively, with a graded relation between the relative risks and the strata of fish consumption (P for trend = 0.04 and 0.02, respectively). These findings were accounted for by the relation of fish consumption to nonsudden death from myocardial infarction (relative risk, 0.33; 95 percent confidence interval, 0.12 to 0.91; P for trend= 0.007).

CONCLUSIONS

These data show an inverse association between fish consumption and death from coronary heart disease, especially nonsudden death from myocardial infarction.

Investigating the use of the chymosin-sensitive sequence of kappa-casein as a cleavable linker site in fusion proteins

The chymosin-sensitive sequence of bovine k-casein A (kappa-CN A) was investigated as a cleavable linker site between the two domains of a streptavidin-chloramphenicol acetyltransferase fusion protein. Two DNA sequences were synthesized which encode the amino acids from 101 to 107 and from 97 to 113 of bovine kappa-CN A. These sequences were separately cloned in-frame to a streptavidin expression vector used for fusion protein construction. The gene for chloramphenicol acetyltransferase (CAT) was then cloned in-frame to a streptavidin-chymosin-sensitive linker vector forming plasmids pStCL1CAT and pStCL2CAT. The fusion protein was expressed in Escherichia coli and SDS-PAGE and Western blot analysis of chymosin-treated cell lysates showed a pH-dependent cleavage of the fusion proteins. Fusion proteins were also bioselectively immobilized onto biotinylated controlled-pore glass beads and treated with chymosin. CAT was specifically released by chymosin treatment and was identified by SDS-PAGE.

The effect of platelet-activating factor (PAF), histamine, and ethanol on vascular permeability of the guinea pig conjunctiva

Increased vascular permeability, one of the characteristic features of immediate hypersensitivity (Type I), is mediated through a variety of compounds, including histamine and platelet-activating factor (PAF), a phospholipid inflammatory mediator. The effects on vascular permeability of histamine, PAF, and ethanol, the solvent for PAF, were compared in the guinea pig conjunctiva. Permeability at 30 min was investigated by evaluation of conjunctival edema and Evans blue extravasation (clinically estimated and colorimetrically measured). Doses of PAF from 1 to 10 nmol produced an increase in vascular permeability, with a peak effect at 10 nmol. Ethanol had no effect on vascular permeability below 40 X 10(3) nmol; above this concentration, however, permeability increased, reaching a maximum at 175 X 10(3) nmol. At low doses of PAF and ethanol, the effects were additive, whereas at 20-80 nmol of PAF with high concentrations of ethanol there was no additive effect of PAF, producing a decrease in the net effect of PAF. Histamine increased vascular permeability, with a minimum effect at 10 nmol and a maximum effect at 450 nmol. The slopes of the dose-response curves for all three compounds were linear and parallel, with statistically different potencies. The potencies for each compound were identical by all three methods of evaluation. Therefore, we conclude that PAF is a potential mediator in hypersensitivity reaction in the guinea pig conjunctiva, and that its effect is similar to but much more potent than that of histamine or ethanol. Since ethanol alone has a significant effect on vascular permeability, studies on PAF effects using control solutions without ethanol may be difficult to interpret.

Trichloroacetic acid (TCA) precipitability of 125I in the blood of mice fed 125I

A recent study showed that after feeding 125I-labelled proteins or free 125I to mice, as much as 40% of total radioactivity in the circulation precipitated upon mixing whole blood with 10% trichloroacetic acid. We examined this potential limitation to the use of radiolabelled tracers for studies on intestinal digestion of proteins and protein uptake, and identified its mechanism. BALB/c mice were gavage-fed or injected intravenously (i.v.) with Na125I. Blood obtained at 15 min was added directly to 10% trichloroacetic acid (TCA) or was processed to obtain serum or plasma. On mixing with 10% TCA, 25-33% of the radioactivity in whole blood was precipitated; less than 2% of the radioactivity in plasma or serum was precipitated. In vitro studies identified hemoglobin as the primary carrier protein participating in this reaction. If hemoglobin was replaced by methemoglobin or cyanomethemoglobin, then the reaction with 125I did not occur, suggesting that iron in the heme group may be the site for 125I binding and that iron must be in its reduced or ferrous form (Fe2+). The administration of non-radioactive NaI in vivo or its addition to reaction mixtures in vitro completely inhibited the precipitation of 125I by hemoglobin in the presence of TCA. Thus the addition of non-radioactive iodide to TCA stock solutions may effectively prevent non-specific binding of 125I to free hemoglobin released unintentionally during venipuncture or at other stages of blood processing.

Transfer of protein antigens into milk after intravenous injection into lactating mice

We investigated the transfer of bovine serum 125I-albumin (125I-BSA), bovine 125I-gamma-globulin (125I-BGG), 125I-ovalbumin (125I-OVA), and 125I-beta-lactoglobulin (125I-BLG) from the blood into the milk of lactating mice. Equal amounts (by weight) of the radiolabeled proteins were injected intravenously into mice 1 wk postpartum. Total radioactivity, trichloroacetic acid-precipitable radioactivity, and specifically immunoprecipitable radioactivity were measured in serum, mammary gland homogenate, and milk. Clearance of immunoreactive OVA (iOVA) and iBLG from the circulation was more rapid than iBSA and iBGG. The radioactivity in mammary tissue associated with BSA and BGG was greater than 70% immunoprecipitable throughout the 4-h test interval; 125I-OVA and 125I-BLG were less than 12% precipitable 1 and 4 h after injection. In milk obtained at 4 h, there was an approximately 10-fold greater accumulation of iBSA or iBGG than of iOVA or iBLG. These experiments demonstrate that protein antigens differ in their ability to transfer from maternal circulation into milk. The transfer into milk appeared to be in proportion to persistence of the antigens in the maternal circulation.

Influence of circulating maternal antibody on the transfer of dietary antigen to neonatal mice via milk

125I-BSA injected intravenously into lactating mice persisted in the circulation for 4 h, entered the mammary gland, and was transferred to the neonate via the milk. When injected with anti-BSA antibodies, it was rapidly cleared from the circulation. Although animals receiving anti-BSA antibodies transferred more radioactivity to the neonate via the milk, the radioactivity was not TCA-precipitable or bound to staphylococcal protein A, nor was it immunoreactive. These findings suggest that circulating maternal antibody can limit the transfer of specific protein antigen from mother to newborn.