Dynamics of SARS-CoV-2 Seroprevalence in a Large US population Over a Period of 12 Months

Due to a combination of asymptomatic or undiagnosed infections, the proportion of the United States population infected with SARS-CoV-2 was unclear from the beginning of the pandemic. We previously established a platform to screen for SARS-CoV-2 positivity across a representative proportion of the US population, from which we reported that almost 17 million Americans were estimated to have had undocumented infections in the Spring of 2020. Since then, vaccine rollout and prevalence of different SARS-CoV-2 variants have further altered seropositivity trends within the United States population. To explore the longitudinal impacts of the pandemic and vaccine responses on seropositivity, we re-enrolled participants from our baseline study in a 6- and 12- month follow-up study to develop a longitudinal antibody profile capable of representing seropositivity within the United States during a critical period just prior to and during the initiation of vaccine rollout. Initial measurements showed that, since July 2020, seropositivity elevated within this population from 4.8% at baseline to 36.2% and 89.3% at 6 and 12 months, respectively. We also evaluated nucleocapsid seropositivity and compared to spike seropositivity to identify trends in infection versus vaccination relative to baseline. These data serve as a window into a critical timeframe within the COVID-19 pandemic response and serve as a resource that could be used in subsequent respiratory illness outbreaks.

Multi-attribute method performance profile for quality control of monoclonal antibody therapeutics

Multi-attribute method (MAM) using peptide map analysis with high resolution mass spectrometry is increasingly common in product characterization and the identification of critical quality attributes (CQAs) of biotherapeutic proteins. Capable of providing structural information specific to amino acid residues, quantifying relative abundance of product variants or degradants, and detecting profile changes between product lots, a robust MAM can replace multiple traditional methods that generate profile-based information for product release and stability testing. In an effort to provide informative and efficient analytical monitoring for monoclonal antibody (mAb) products, from early development to manufacturing quality control, we describe the desired MAM performance profile and address the major scientific challenges in MAM method validation. Furthermore, to support fast speed investigational product development, we describe a platform method validation strategy and results of an optimized MAM workflow. This strategy is applied to support the use of MAM for multiple mAb products with similar structures and physicochemical properties, requiring minimal product-specific method validation activities. Three mAb products were used to demonstrate MAM performance for common and representative product quality attributes. Method validation design and acceptance criteria were guided by the Analytical Target Profile concept, as well as relevant regulatory guidelines to ensure the method is fit-for-purpose. A comprehensive system suitability control strategy was developed, and reported here, to ensure adequate performance of the method including sample preparation, instrument operation, and data analysis. Our results demonstrated sufficient method performance for the characteristics required for quantitative measurement of product variants and degradants.

Sex-differences and utility of treadmill testing in identification and genotype prediction in LQTS: a sub-study of the national LQTS registry and Canadian Hearts in Rhythm registry

Background/Purpose

Long-QT (LQT) Syndrome is an inherited heart rhythm condition presenting with QT-prolongation and failure to shorten with exercise, leading to life-threatening cardiac events. The prevalent normal-to-borderline phenotype remains a challenge for diagnosis. A three-step algorithm was developed to predict genotype from phenotypic characteristics with exercise testing. Sex-specific cut offs for determining a prolonged corrected QT value are 470ms for males and 480ms for females, serving as step 1 in the algorithm. The purpose of this study is to validate the algorithm using a national cohort that is more representative of the general LQT population, with a milder phenotype and more frequent ambiguity in phenotype.

Methods

A review of cases in the Canadian National Long-QT Registry, housed in the HiRO Registry was undertaken. Eligible cases from September 2014 to May 2020 were included. Gene-positive patients included 93 probands and 122 first-degree relatives (FDR) with a likely-pathogenic or pathogenic mutation according to ACMG criteria, limited to LQT1/2 subtypes, with 164 and 51 patients, respectively. Controls were composed of 39 gene-negative FDRs. Continuous variables were compared by the Mann-Whitney U test for 2-group comparisons, and Kruskal-Wallis test for multiple group comparisons. The predictive value of exercise ECG characteristics were analysed using ROC analysis and optimal cut-off values for exercise ECG characteristics (supine, standing, peak exercise, 1 and 4-minutes into recovery) were determined for males and females, using a sensitivity of 0.80 for carrier status and 0.75 for subtype.

Results

The 4-minute recovery QTc had the best predictive value for males, with an AUC of 0.86, and a cut-off point of 442ms given a sensitivity of 0.81 and specificity of 0.86. The 4-minute recovery QTc yielded an AUC of 0.79 for females, with a cut-off of 452ms given a sensitivity of 0.81 and specificity of 0.71. The 1-minute recovery QTc had the best predictive value for females, with an AUC of 0.92 and a cut-off point of 424ms given a sensitivity of 0.82 and specificity of 0.94. In prediction of LQT1, the 1-minute recovery QTc yielded the highest AUC for both males and females, at 0.68 and 0.80, respectively. Males had a cut off of 428ms with a sensitivity of 0.75 and specificity of 0.47, while females had a cut off of 451ms given a sensitivity of 0.76 and specificity of 0.75.

Conclusion

The current study demonstrates that exercise testing is a valid approach to diagnosing LQTS, with a differential optimal best measurement in males vs. females. Test performance measured by AUC was generally better at all time points in females compared to males. The algorithm is a reliable and simple method for the identification and prediction of genotype for probands and FDR carriers. The algorithm should be sex-stratified at the second step, with the 4-minute recovery QTc used for males and the 1-minute recovery QTc for females.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Canadian Institute of Health Research

Generic Protocols for the Analytical Validation of Next-Generation Sequencing-Based ctDNA Assays: A Joint Consensus Recommendation of the BloodPAC's Analytical Variables Working Group

Liquid biopsy, particularly the analysis of circulating tumor DNA (ctDNA), has demonstrated considerable promise for numerous clinical intended uses. Successful validation and commercialization of novel ctDNA tests have the potential to improve the outcomes of patients with cancer. The goal of the Blood Profiling Atlas Consortium (BloodPAC) is to accelerate the development and validation of liquid biopsy assays that will be introduced into the clinic. To accomplish this goal, the BloodPAC conducts research in the following areas: Data Collection and Analysis within the BloodPAC Data Commons; Preanalytical Variables; Analytical Variables; Patient Context Variables; and Reimbursement. In this document, the BloodPAC's Analytical Variables Working Group (AV WG) attempts to define a set of generic analytical validation protocols tailored for ctDNA-based Next-Generation Sequencing (NGS) assays. Analytical validation of ctDNA assays poses several unique challenges that primarily arise from the fact that very few tumor-derived DNA molecules may be present in circulation relative to the amount of nontumor-derived cell-free DNA (cfDNA). These challenges include the exquisite level of sensitivity and specificity needed to detect ctDNA, the potential for false negatives in detecting these rare molecules, and the increased reliance on contrived samples to attain sufficient ctDNA for analytical validation. By addressing these unique challenges, the BloodPAC hopes to expedite sponsors' presubmission discussions with the Food and Drug Administration (FDA) with the protocols presented herein. By sharing best practices with the broader community, this work may also save the time and capacity of FDA reviewers through increased efficiency.

Bioinformatics Tools and Resources for Cancer Immunotherapy Study

In recent years, cancer immunotherapy has emerged as a highly promising approach to treat patients with cancer, as the patient's own immune system is harnessed to attack cancer cells. However, the application of these approaches is still limited to a minority of patients with cancer and it is difficult to predict which patients will derive the greatest clinical benefit.One of the challenges faced by the biomedical community in the search of more effective biomarkers is the fact that translational research efforts involve collecting and accessing data at many different levels: from the type of material examined (e.g., cell line, animal models, clinical samples) to multiple data type (e.g., pharmacodynamic markers, genetic sequencing data) to the scale of a study (e.g., small preclinical study, moderate retrospective study on stored specimen sets, clinical trials with large cohorts).This chapter reviews several publicly available bioinformatics tools and data resources for high throughput molecular analyses applied to a range of data types, including those generated from microarray, whole-exome sequencing (WES), RNA-seq, DNA copy number, and DNA methylation assays, that are extensively used for integrative multidimensional data analysis and visualization.

Design and development of the molecular analysis for Therapy Choice (NCI-MATCH) Designated Laboratory Network

3016

Background: NCI-MATCH is a precision medicine trial that assigns treatment to refractory cancer patients by tumor mutation profile rather than by histology. After screening fresh tumor biopsies from nearly 6000 patients many treatment arms did not meet accrual due to the low prevalence of the eligible variants. NCI MATCH developed an approach to identify patients for the remaining arms utilizing a network of academic and commercial CLIA-certified labs that perform NGS assays as routine care at MATCH participating sites. Methods: Candidate labs were recruited through a notice in the Federal Register and posted on the NCI and ECOG ACRIN web sites. Twenty-seven labs (17 academic/10 commercial) submitted applications. After acceptance each lab analyzed a common set of 10 DNAs extracted from 8 cell lines and 2 clinical samples for concordance with the central NCI-MATCH NGS assay. Results: For the 17 labs with concordance results, a median of 8 (range 2 – 58) copy number variants (CNVs) were evaluated by the NGS assay of each DL, with the number evaluated depending on each lab’s clinical assay panel content. CNV concordance between central and DL assays, as measured by positive percent agreement (PPA), averaged 98.7% (range 87.5% - 100%) with the central assay as referent and 94.1% (range 77.8% – 100%) with the DL assay as referent. For single nucleotide variants (SNVs) and Insertion/deletions (Indels) combined, a median of 19 variants (range 11 – 26) were evaluated by each DL for concordance. PPA between central and DL assays averaged 98.0% (range 87.5% – 100%) and 98.6% (range 90.0% – 100%) with central and DL assay as referents, respectively. Strong correlations were observed between central and DL assays for both CNVs (median r = 0.93; 0.33 – 1.00) and SNV/Indels (median r = 0.98; 0.67 – 0.99). Conclusions: Our results suggest that different NGS assay platforms using diverse strategies for target enrichment and data analysis may still achieve high concordance if pre-analytical variables are minimized and the common genomic regions interrogated by each assay are well-understood. The designated lab network allows for a wider search for rare variants in tumors and provides a model for conducting future clinical trials. Clinical trial information: NCT02465060.

Influence of Personal Exposure to the Cancer of a Loved One on the Breast Cancer Prevention Decisions of High Risk Women

Purpose: To explore the impact of close personal exposure to cancer in a family member or friend in the prevention decisions of women at elevated risk of breast cancer. Methods: 50 semi-structured interviews with women at elevated risk of breast cancer, focusing on perceptions of risk; risk information; consideration of prevention options; decision-making processes and networks, and psychosocial well-being. Transcribed data are analyzed with NVivo 10, using grounded theory methods. Results: Prevention decision making by women who have had close contact with the cancer diagnosis and treatment of a loved one (most often a mother or grandmother, but sometimes a sister, cousin, or close friend) is importantly influenced by these experiences. The process of deciding whether and when to undertake prophylactic mastectomy or oophorectomy, chemoprevention, enhanced surveillance, and/or genetic testing is substantially different in women who have and have not had close personal experience with the cancer of a loved one. Women who have experienced the deaths of one or more loved ones express strong motivation and willingness to undertake definitive interventions; most often this means prophylactic surgery, but this can also include chemoprevention. These women often feel that they are likely to be diagnosed with breast cancer eventually, and seek decisive methods to avoid what they perceive as a life-threatening diagnosis. Women whose loved ones have survived and thrived after a cancer diagnosis are more oriented toward careful surveillance through screening tests and physician checks. These women usually see breast cancer as a challenge they may have to deal with in the future, and they are motivated to set the stage for treatment success by establishing ongoing relationships with highly competent healthcare providers, and by being diagnosed as early as possible. Conclusions: Cancer care has strong effects beyond the cancer patient herself, affecting the decision-making processes and the prevention-related decisions of loved ones as well. Future prevention research for women at elevated risk should consider how their prior experiences with the cancer of friends or family members structure women's expectations of cancer risk, prevention, and outcomes.

Phase Ib study of recombinant human Apo2L/TRAIL plus irinotecan and cetuximab or FOLFIRI in metastatic colorectal cancer (mCRC) patients (pts): Preliminary results

4129

Background: Preclinical data suggest that recombinant human Apo2 ligand/TNF-related apoptosis-inducing ligand (rhApo2L/TRAIL) induces tumor cell death through pro-apoptotic receptors DR4 and DR5. In specific mouse xenograft colon cancer models, tumors regressed in the majority of mice given rhApo2L/TRAIL and irinotecan. In this ongoing study of rhApo2L/TRAIL in previously treated mCRC pts, the primary objectives are to assess the safety and pharmacokinetics of rhApo2L/TRAIL combined with irinotecan and cetuximab or FOLFIRI. Methods: As of 12/12/08, 30 pts have received rhApo2L/TRAIL (on Days 1–5) with irinotecan (on Day 1) and cetuximab (on Days 1, 8, and 15) in 21-day cycles; rhApo2L/TRAIL dose cohorts range from 1.5–8 mg/kg/day. 5 pts have received rhApo2L/TRAIL 9 mg/kg (on Days 1–3) with FOLFIRI (leucovorin, 5-FU, and irinotecan on Day 1) in 14-day cycles. Results: In the first cohort, rhApo2L/TRAIL was given at 4 mg/kg/d with irinotecan (350 mg/m2) and cetuximab; the first 3 pts developed Grade 3–4 neutropenia. The study was amended to allow irinotecan dose reductions to 300 mg/m2 for pts at risk for irinotecan-related toxicities and patients were started on a lower dose of Apo2L/TRAIL at 1.5 mg/kg/d. An additional 32 pts received rhApo2L/TRAIL at 1.5–9 mg/kg/d. The most common adverse events thus far are diarrhea, fatigue, and nausea. A pt with anemia at screening developed Grade 4 anemia DLT. 2 pts (1 with progressive liver disease) discontinued therapy due to elevated ALT. Conclusions: Preliminary data indicate that rhApo2L/TRAIL can be safely combined with irinotecan-based regimens. Full data will be available by June 2008. A phase II study of rhApo2L/TRAIL with FOLFIRI should provide more information on safety, efficacy, and a potential diagnostic for rhApo2L/TRAIL.

[Table: see text]

Septic arthritis in a native joint due to Anaerococcus prevotii

A 37-year-old injecting drug user presented with signs and symptoms of septic arthritis. Staphylococcus aureus was grown from his blood cultures. Despite treatment with flucloxacillin and fusidic acid his condition continued to deteriorate. Echocardiography showed no signs of endocarditis. Culture of his knee aspirate grew Anaerococcus prevotii after 5 days of incubation. Metronidazole was added to his treatment regime. A collection of pus (800 ml) was drained from the right thigh and A prevotii was isolated. His condition improved gradually and he was subsequently transferred to a drug rehabilitation unit after completing his antibiotic course. The importance of anaerobic streptococci in septic arthritis, as a very rare cause, is highlighted.

Genomewide clonal analysis of lethal mutations in the Drosophila melanogaster eye: comparison of the X chromosome and autosomes

Using a large consortium of undergraduate students in an organized program at the University of California, Los Angeles (UCLA), we have undertaken a functional genomic screen in the Drosophila eye. In addition to the educational value of discovery-based learning, this article presents the first comprehensive genomewide analysis of essential genes involved in eye development. The data reveal the surprising result that the X chromosome has almost twice the frequency of essential genes involved in eye development as that found on the autosomes.

A phase IB safety and pharmacokinetic (PK) study of recombinant human Apo2L/TRAIL in combination with rituximab in patients with low-grade non-Hodgkin lymphoma

8078

Background: Recombinant human Apo2L/TRAIL (rhApo2L/TRAIL) induces apoptosis (programmed cell death) through binding to the pro-apoptotic receptors DR4 and DR5. Preclinical studies show that rhApo2L/TRAIL selectively induces apoptosis in many cancer cell lines derived from various malignancies including NHL, while sparing most normal cells. In vivo, rhApo2L/TRAIL and Rituximab cooperate to shrink or attenuate the growth of various NHL tumor xenografts in SCID mice. RhApo2L/TRAIL is being co-developed by Genentech and Amgen as a targeted therapy for solid tumors and hematologic malignancies. Methods: Subjects were eligible to participate if they had CD20+ follicular NHL or small lymphocytic lymphoma or marginal zone B-cell lymphoma that had progressed following stable disease or an objective response lasting > 6 months duration to the most recent rituximab-contain regimen. RhApo2L/TRAIL is administered intravenously over 1 hour for 5 consecutive days every three weeks up to 4 cycles at dose levels of 4 and 8 mg/kg. Rituximab is administered intravenously at 375 mg/m2 weekly for up to eight doses. Results: Six subjects with low grade NHL (4 with follicular NHL and 2 with small cell NHL) have been enrolled and treated with 4 mg/kg rhApo2L/TRAIL and rituximab, and one subject (with follicular NHL) has been enrolled and treated with 8 mg/kg rhApo2L/TRAIL and rituximab. The enrolled subjects range in age from 39–82 years; there are 6 male and 1 females. The number of prior therapies for NHL range from 1–8. Four subjects have received all protocol specified therapy. There have been no DLTs or SAEs or Grade 3/4 adverse events reported to date. To date, five subjects have undergone tumor response assessment: there have been 2 patients with complete response, 1 with partial response and 2 with stable disease. Conclusion: The combination of rhApo2L/TRAIL at 4 mg/kg/day and rituximab appears safe and shows evidence of activity in subjects with low grade NHL that has relapsed following previous rituximab-containing therapy. Enrollment is continuing to test rhApo2L/TRAIL at 8 mg/kg plus rituximab for expanded safety data and further dose optimization.

No significant financial relationships to disclose.

Open-label study to assess effect of omeprazole (O) on pharmacokinetics of bortezomib (B) in subjects with advanced solid tumors, NHL, or multiple myeloma

13000

Background: Omeprazole (O), an over-the-counter proton pump inhibitor, is also a potent inhibitor of cytochrome P450 (CYP) 2C19, an enzyme responsible for the metabolism of many drugs including bortezomib (B; VELCADE®). This study sought to evaluate potential drug interactions between omeprazole and bortezomib. Methods: Between January 2005 and August 2006, 18 men and 9 women were randomized to receive B 1.3 mg/m2 iv alone on Days 1, 4, 8, and 11 of a 21-day cycle or B + O 40 mg (2 x 20 mg capsules) on the mornings of Days 6–10 and the evening of Day 8 in Cycle 1, crossing over to receive the other treatment in Cycle 2. Baseline plasma samples were collected before B administration on Day 1 Cycle 1 and Day 8. Results: 17 patients completed both cycles and were evaluable for pharmacokinetics (PK) analysis. The PK of bortezomib with and without omeprazole overlapped and the peak concentrations and time to reach peak concentrations were similar (Table). As observed in other studies of B, there was a high degree of inter-subject variability (B alone, %CV = 64.7; B + O %CV = 60.3); however, differences in mean exposure values between treatments were within the degree of inter- subject variation. There was no increase in adverse events related to bortezomib as a result of treatment with O. In both groups over 95% of patients had over 80% 20S proteasome inhibition. No meaningful relationships were apparent among CYP gene polymorphisms (2C19, 2D6, 3A4, 3A5) and PK endpoints (AUC8 and Cmax) or pharmacodynamic (PD) endpoints (AUE72 and Emax) in either group or both groups combined. Conclusion: Addition of O to B did not alter PK, PD or safety parameters. Clinically significant drug interaction is unlikely when B is co-administered with O or other CYP2C19 inhibitors.

[Table: see text]

No significant financial relationships to disclose.

A phase 2 study to evaluate the efficacy of darbepoetin-alfa administered using an extended dose schedule versus weekly dosing in cancer patients with chemotherapy-induced anemia

19501

Background: Chemotherapy-induced anemia (CIA) can be effectively treated with darbepoetin alfa (DA) using different dosing schedules. Since chemotherapy (CTX) regimens involve various dosing schedules, the ability to synchronize DA dose with CTX could be beneficial. Methods: This phase 2, 25-week (wk), randomized, open-label study compares the efficacy and safety of DA administered using an extended dose schedule (EDS) (every 2 wks [Q2W] or every 3 wks [Q3W]) vs weekly (QW) dosing in patients (pts) with CIA. Pts were randomly assigned to receive DA EDS (either 300 mcg Q2W [with CTX QW, Q2W, or Q4W] or 500 mcg Q3W [with CTX Q3W]) vs 150 mcg DA QW (with CTX QW, Q2W, Q3W, or Q4W). Randomization was stratified by length of CTX cycle, screening hemoglobin (Hb) (< 10 vs = 10 g/dL), and type of cancer (lung/gynecological vs other cancers). The primary endpoint was the change in Hb from baseline (BL) to wk 13; other endpoints included the change in Hb from BL to end of study (EOS), percentage of pts with = 1 transfusion (TFN) from BL to wk 13 and EOS, and safety. Results: Final data for the total 25-wk study period will be presented. Results from a planned interim analysis for all pts who were enrolled in the study and received = 1 dose of DA (n = 752) are shown for wk 13 endpoints (Table). The groups had similar mean change in Hb from BL to wk 13, with a difference (QW minus EDS) (95% CL) of 0.2 (-0.1, 0.4) g/dL. The % pts who achieved target Hb were also similar (difference [95% CL] = 0 [-7, 6]). At the time of the interim analysis, the incidence and types of adverse events were similar between the groups. Ten (3%) EDS and 15 (4%) QW pts had thromboembolic events, 5 (1%) EDS and 2 (1%) QW pts had cerebrovascular accidents, and 19 (5%) EDS and 22 (6%) QW pts had died. Conclusions: This is the first trial synchronizing DA dosing (Q2W and Q3W) with CTX schedules. The interim results suggest that DA administered once per CTX cycle is well-tolerated and efficacious in these patients.

[Table: see text]

No significant financial relationships to disclose.

Does sodium hyaluronate- and carboxymethylcellulose-based bioresorbable membrane (Seprafilm) decrease operative time for loop ileostomy closure?

BACKGROUND

Adhesions can result in serious clinical complications and make ileostomy closure, which is relatively simple procedure into a complicated and prolonged one. The use of sodium hyaluronate and carboxymethyl cellulose membrane (Seprafilm) was proven to significantly reduce the postoperative adhesions at the site of application. The aim of this study was to assess the incidence and severity of adhesions around a loop ileostomy and to analyze the length of time and morbidity for mobilization at the time of ileostomy closure with and without the use of Seprafilm.

METHODS

Twenty-nine surgeons from 15 institutions participated in this multicenter prospective randomized study. 191 patients with loop ileostomy construction were randomly assigned to either receive Seprafilm under the midline incision and around the stoma (Group I), only under the midline incision (Group II), or not to receive Seprafilm (Group III). At ileostomy closure, adhesions were quantified and graded; operative morbidity was also measured.

RESULTS

All 3 groups were comparable relative to gender, mean age and number of patients with prior operations (26, 25 and 19, respectively). Group II patients were significantly more likely to have pre-existing adhesions than Group III patients (30.6% vs. 14.1%, p = 0.025). At stoma mobilization, significantly more patients in Group III than in Group I had adhesions around the stoma (95.2% vs. 82.3%, p = 0.021). Mean operative times were 27, 25, and 28 minutes, respectively (p = 0.38), with significant differences among sites. There was no significant difference in the number of patients needing myotomy or enterotomy (29, 27 and 24 patients, respectively), nor in the number of postoperative complications (7, 9 and 7 patients, respectively).

CONCLUSIONS

When consistently applied, Seprafilm significantly decreased adhesion formation around the stoma but not operative times without any increase in the need for myotomy or enterotomy. These findings were not seen in the overall study population possibly due to the large number of surgeons using a variety of application techniques.

Stability of dopamine and epinephrine solutions up to 84 hours

OBJECTIVES

The current practice of preparing fresh dopamine and epinephrine solutions every 24 hrs may lead to hemodynamic instability caused by the interruption of infusions with each change. We determined the stability of these catecholamines over an 84-hr period and whether stability was enhanced by dextrose-containing solutions.

SETTING

Tertiary care teaching hospital.

DESIGN

The stability of dopamine and epinephrine, each at three commonly used concentrations, was studied in three vehicles (10 gm/dl dextrose in water [D10W], 5 gm/dl dextrose in water [D5W], and 0.9% NaCl in water [NS]). To mimic clinical conditions, solutions were placed on syringe pumps infusing continuously into a closed system at ambient temperature for 84 hrs.

MEASUREMENTS

Concentrations of dopamine in mg/ml and epinephrine in microg/ml were measured by high-performance liquid chromatography at 0, 24, 36, 48, 72, and 84 hrs.

RESULTS

Dopamine and epinephrine concentrations did not change over the 84-hr period regardless of the vehicles in which the drugs were prepared.

CONCLUSIONS

Clinically relevant concentrations of dopamine and epinephrine remain stable in dextrose- and saline-containing solutions for >or=84 hrs. These data suggest that solutions of these catecholamines may safely be used in clinical practice beyond the currently recommended 24 hrs.

Suppression of pRB expression in normal human mammary epithelial cells is associated with resistance to all-trans-retinoic acid but not N-(4-hydroxylphenyl)-retinamide

Despite the widespread clinical use of synthetic and naturally occurring retinoids, the down stream targets of retinoids have not been fully characterized. We observe that G(1/0)-phase arrest induced by all-trans-retinoic acid (ATRA) in normal human mammary epithelial cells (HMECs) is temporally associated with a significant decrease in the levels of hyperphosphorylated retinoblastoma protein (pRB). Suppression of pRB protein expression in HMECs by retroviral-mediated expression of the E7 protein of the human papillomavirus strain 16 (HPV-16) was associated with resistance to ATRA-mediated growth arrest but not to the synthetic retinoid N-(4-hydroxyphenyl) retinamide (4-HPR or fenretinide). 4-HPR but not ATRA induced apoptosis in HMECs independent of the level of pRB protein expression. These observations suggest that ATRA- but not 4-HPR-mediated growth arrest may be dependent on the coordinated expression of pRB and emphasize the chemotherapeutic potential of 4-HPR, particularly for suppressing growth of tumors lacking pRB function.

Chiral high-performance liquid chromatographic analysis of fluoxetine and norfluoxetine in rabbit plasma, urine, and vitreous humor using an acetylated beta-cyclodextrin column

Fluoxetine (Prozac) is a potent selective serotonin reuptake inhibitor used for the treatment of major depression. Both fluoxetine (F) and its demethylated metabolite, norfluoxetine (NF), are racemic. S-Fluoxetine (SF) and S-norfluoxetine (SNF) are more potent inhibitors of serotonin reuptake than R-fluoxetine (RF) and R-norfluoxetine (RNF). Quantitation of individual enantiomers may provide a greater understanding of pharmacokinetic properties. The objective of this study was to perform a limited chiral selectivity study using rabbit plasma, urine, and vitreous humor analyzed by a solid-phase extraction protocol and a newly developed chiral analysis with an acetylated beta-cyclodextrin (CD) column. Liquid chromatographic parameters for CD were as follows: a mobile phase composition of methanol/0.3% triethylamine buffer, pH 5.6, (30:70), a flow rate of 1 mL/min, detection at 214 nm, and a temperature of 40 degrees C. Elution order was SNF, SF, RNF, and RF with capacity factors of 6, 7, 8, and 9, respectively. The corresponding resolution factors were as follows: R1,2 = 0.8, R2,3 = 1.2, and R3,4 = 0.9. The conditions for solid-phase extraction were optimized for Varian Bond Elut Certify columns. Following sample application, the column was rinsed with water, acetic acid, and then with methanol. Drug enantiomers were eluted with methylene chloride, isopropanol, and ammonium hydroxide (78:20:2). After extract evaporation, the extract residue was reconstituted for high-performance liquid chromatographic analysis. To investigate chiral pharmacology, a biodistribution study was performed by administering 2 mg/kg of F to five rabbits. Blood, urine, and vitreous specimens were collected. Plasma samples collected 45 min postinjection showed nearly equal concentrations of RF and SE After 24 h, the only metabolite detected in plasma was RNF. Drugs were not detectable in vitreous humor. Urine concentrations of SNF, SF, RNF, and RF were 51, 76, 34, and 8 microg/L, respectively. The CD column along with the described extraction protocol may be used for a chiral selectivity study of fluoxetine.

The clinical spectrum of Clostridium sordellii bacteraemia: two case reports and a review of the literature

Clostridium sordellii is rarely associated with disease in humans. Since its first report in 1922 only a few cases of bacteraemia have been reported. This report describes two cases of C sordellii bacteraemia; the oldest and youngest patients reported to date. The first, is a previously well 81 year old woman presented with perianal infection, which was later complicated by thrombosis of the aorta, and the second is a 12 year old boy with epilepsy who presented with an ear infection. These cases are also highlighted to demonstrate the wide spectrum of presentation of sordellii bacteraemia.

Follow up study eight years after diagnosis of sexual abuse

AIM

To study the outcome over an eight year period of children determined by paediatricians in 1989 as definitely or probably sexually abused.

METHOD

Information was obtained on 140 of 148 children diagnosed in 1989 when aged 7 or less. Sources were hospital medical records and school health records. School health records of a comparison group of 83 children were also examined.

RESULTS

A variety of problematic characteristics were found significantly more often in the abused group than the comparison group. These included surname changes (30% v 2%), removal from home (25% v 1%), number of home addresses (2.8 v 1.4), and schools attended (3.4 v 2.2). Other significant findings included further abuse (35% v 0%), adverse behaviours (60% v 16%), educational problems (24% v 5%), chronic health problems (54% v 36%), and involvement of mental health services (32% v 1%).

Overexpression of sialomucin complex, a rat homologue of MUC4, inhibits tumor killing by lymphokine-activated killer cells

Sialomucin complex (SMC) is a large heterodimeric glycoprotein complex composed of a mucin subunit ascites sialoglycoprotein-1 and a transmembrane subunit ascites sialoglycoprotein-2. It is a rat homologue of human mucin gene MUC4 and is abundantly expressed on the cell surface of highly metastatic ascites 13762 rat mammary adenocarcinoma cells. Because of their extended and rigid structures, mucin-type glycoproteins are suggested to have suppressing effects on cell-cell and cell-matrix interactions. During the metastatic process, these effects presumably cause tumor cell detachment from the primary tumor mass and facilitate escape of the tumor cells from immunosurveillance. Analyses of human breast cancer cells in solid tumors and tumor effusions showed that the more aggressive cells in effusions are stained with polyclonal antibodies against SMC more frequently than cells in solid tumors, suggesting a role for MUC4/SMC in tumor progression and metastasis. Previously, we generated recombinant cDNAs for SMC that vary in the number of mucin repeats to study the putative functions of SMC in tumor metastasis. These cDNAs were transfected into human cancer cell lines and tested for the effect of the expression of this gene. Here, using a tetracycline-responsive inducible expression system, we demonstrate that overexpression of SMC masks the surface antigens on target tumor cells and effectively suppresses tumor cell killing by cytotoxic lymphocytes. This effect results from the ability of SMC to block killer cell binding to the tumor cells and is dependent on both overexpression of the mucin and the number of mucin repeats in the expressed SMC. These results provide an explanation for the proposed role of SMC/MUC4 in tumor progression.

Barriers to meeting the mental health needs of the Chinese community

BACKGROUND

This study aimed to identify the barriers encountered by Chinese people with mental health needs in England which hindered their obtaining appropriate help from the National Health Service (NHS).

METHODS

Attenders at Chinese community centres in health authority districts with resident Chinese population in excess of 2000 were invited to fill in a 12-item Chinese Health Questionnaire (12-CHQ). Individuals who scored two or above, indicating a high probability of a mental health problem, were invited to undertake a semi-structured interview.

RESULTS

A total of 401 completed the 12-CHQ. Eighty-six (21.4 per cent) screened positive and 71 (82.6 per cent) agreed to be interviewed. Although 70 (98.6 per cent) were registered with a general practitioner (GP), there were long delays before they made contact with health professionals, and the GP was the first port of call for help in only 27 (38.6 per cent) interviewees. Fifty-two (74.3 per cent) had encountered difficulties when they sought professional help. The main barriers were language, interviewees' perceptions of symptoms as somatic rather than psychiatric in origin, lack of knowledge about statutory services, and lack of access to bilingual health professionals. Doctors, particularly GPs, were pivotal in the management of their conditions. The majority were prescribed psychiatric medication with only a small number in contact with community psychiatric services. Unemployment and social exclusion were common. Stigma associated with mental illness and limited knowledge in the community were identified as the causes for the widespread discrimination experienced by the interviewees.

CONCLUSION

The mental health needs of these Chinese people were not adequately met by statutory services, nor could they rely on family and friends for care and support. Training for health service staff and access to health advocates are essential to maximize the effectiveness of health professional-patient contacts. The promotion of better understanding of mental illness by the Chinese community is important, and greater flexibility within the NHS is required to ensure those professionals with bilingual skills are used to the best effect.

Phase I clinical and pharmacological studies of benzylacyclouridine, a uridine phosphorylase inhibitor

Benzylacyclouridine (BAU, IND 039655) is a potent and specific inhibitor of uridine phosphorylase (UrdPase; EC 2.4.2.3). This enzyme plays a major role in regulating uridine homeostasis and also catalyzes the conversion of fluoropyrimidine nucleosides to their respective bases. Inhibition of UrdPase enzyme activity 18-24 h after 5-fluorouracil (5-FU) administration increased plasma levels of uridine and enhanced the therapeutic index of 5-FU by rescuing normal tissues. Moreover, in vitro preclinical studies have also shown that inhibiting UrdPase enzyme activity by BAU prior to administration of 5-FU increased cytotoxicity in a number of human cancer cell lines. A series of preclinical studies was performed in dogs and pigs to evaluate the pharmacological and pharmacodynamic properties of BAU. These data showed a sustained elevation in plasma uridine concentration in both animal models. The rapid degradation of a tracer dose of uridine into uracil was virtually arrested by BAU administered both p.o. or i.v. The t1/2 of BAU was 1.8-3.6 h in dogs, with bioavailability levels of 85% (30 mg/kg) and 42.5% (120 mg/kg). In pigs, the half-life varied from 1.6 to 2.3 h, with a bioavailability of 40% at 120 mg/kg. The drug was distributed into most tissues with a tissue: plasma ratio of approximately 0.7. On the basis of these preclinical studies, we performed a Phase I clinical trial of BAU in patients with advanced cancer. Patients received 200, 400, 800, and 1600 mg/m2 BAU as a single oral dose. Toxicities included grade 2 anemia, grade 1 fever, grade 1 fatigue, grade 1 constipation, and grade 1 elevation in alkaline phosphatase; none of these toxicities were observed to be dose dependent. The maximum tolerated dose and dose-limiting toxicity were not reached at the doses given. BAU plasma concentrations and area under the curve correlated linearly with the oral dose level. The pharmacokinetics of BAU were consistent with a first-order clearance, with average peak concentrations ranging from 19 microM (200 mg/m2) to 99 microM (1600 mg/m2) and tbeta1/2 ranging from 3.0 to 3.9 h at the four dose levels. Compared with baseline plasma uridine, treatment of patients with 200, 400, 800, and 1600 mg/m2 BAU increased peak uridine concentrations by 120, 150, 250, and 175%, respectively. On the basis of this clinical study, the suggested Phase II starting dose of BAU in combination with 5-FU is 800 mg/m2. Studies combining BAU with 5-FU and incorporating appropriate molecular and biochemical end points to assess the effects of this drug combination on tumor and/or surrogate tumor tissue are under way.

Health care costs of worksite health promotion participants and non-participants

Total and lifestyle-related medical care costs for employees of a major corporation participating in a worksite health promotion (WHP) program over a three-year period were compared with the costs for non-participants in a cross-sectional study. The study population consisted of 8,334 active employees based in the Cincinnati headquarters of The Procter & Gamble Company. Adjusting for age and gender, participants (n = 3,993) had significantly lower health care costs (29% lower total and 36% lower lifestyle-related costs) when compared with non-participants (n = 4,341) in the third year of the program. Similarly, in the third year of the program, participants had significantly lower inpatient costs, fewer hospital admissions, and fewer hospital days of care when compared with non-participants. No significant differences in costs were found between participants and non-participants during the first two years of the WHP program. Conclusions drawn from this study are that long-term participation in a WHP that includes high-risk screening and intensive one-on-one counseling results in lower total and lifestyle-related health care costs, as well as lower utilization of hospital services.

Phase I trial of weekly paclitaxel in advanced lung cancer

PURPOSE

We conducted a phase I study in chemotherapy-naive patients with advanced non-small-cell lung cancer (NSCLC) to determine the maximum-tolerated dose (MTD) of paclitaxel using an extended weekly schedule.

PATIENTS AND METHODS

Patients with stage IIIB/IV NSCLC were treated with paclitaxel administered weekly over 3 hours for 6 weeks of an 8-week cycle. Doses were modified for granulocyte counts less than 1,800/microL or neurotoxicity greater than grade I. Groups of three patients were entered at each dose level. The dose was escalated to the next level if less than 50% of patients developed unacceptable toxicity and received more than 80% of the intended first-cycle dose.

RESULTS

Twenty-six patients were entered through six dose levels (100, 125, 135, 150, 175, and 200 mg/m2/wk). Four of six patients at the 175-mg/m2 dose level and only one of six patients at the 200-mg/m2 level received all scheduled doses of paclitaxel during cycle 1. Neutropenia was dose-limiting. Fourteen patients were treated with subsequent cycles of paclitaxel. Grade II to III neuropathy developed in five of 24 patients. It occurred more commonly with greater duration of therapy, but improved following dose reduction. Nine of 26 (35% +/- 10%) patients demonstrated an objective response.

CONCLUSION

The MTD of paclitaxel using a weekly schedule is 175 mg/m2/wk for 6 of 8 weeks. Neutropenia limits dosing acutely, but neuropathy is limiting with sustained therapy. This schedule of paclitaxel results in a twofold to threefold increase in dose-intensity with less toxicity than anticipated from conventional dosing. Further evaluation of this schedule is warranted to assess efficacy and toxicity of prolonged administration.

Prophylactic cranial irradiation in small cell lung cancer: rationale, results, and recommendations

The utility of prophylactic cranial irradiation (PCI) in patients with small cell lung cancer (SCLC) constitutes one of the longest running debates in oncology. Despite dozens of prospective and retrospective studies and decades of individual experience, a consensus has been reached on only two issues: (1) when administered to all patients with SCLC, PCI decreases the likelihood of developing brain metastases by about half, but (2) PCI does not significantly prolong survival. Uncertainty persists over many critical questions, including whether, when, and how to administer PCI; whether identifiable subgroups of patients benefit more tangibly from PCI; how frequent and severe the long-term side effects of PCI are; whether withholding treatment until brain metastases are diagnosed is clinically responsible and cost effective; and how newer forms of treatment for brain metastases should be integrated into the picture. In this review, we discuss the epidemiology and natural history of brain metastases in patients with SCLC, the results of studies examining the efficacy of PCI, data on the early and late toxicities of PCI, and the status of alternative therapies for patients with brain metastases from SCLC. Based on this information, an approach to newly diagnosed patients is suggested, and recommendations for future study are made.

Measles virus serology in Crohn's disease

BACKGROUND

There is evidence that measles virus infection in early life may predispose to Crohn's disease.

AIMS

To examine using serological methods a potential association between measles virus infection in early life and predisposition to Crohn's disease.

SUBJECTS

Forty five patients with Crohn's disease and forty five healthy controls were studied prospectively.

METHODS

Clinical data were recorded and serum was analysed for measles virus, cytomegalovirus (CMV), adenovirus and herpes simplex virus (HSV) antibody titres by a complement fixation test (CFT), and for measles virus IgM by enzyme linked immunosorbent assay (ELISA).

RESULTS

Reciprocal CFT titres for measles virus were lower in patients with Crohn's disease compared with controls (p < 0.05); there was no significant difference in titres for other viruses. None of the subjects studied had a level of measles virus IgM suggestive of acute infection, and there was no significant difference in measles virus IgM levels between patients and controls. The measles virus CFT titres and IgM levels in the patients with Crohn's disease did not correlate with any of the clinical features recorded.

CONCLUSION

This study does not provide supportive evidence for a role for measles virus in the aetiology of Crohn's disease.

Adaptive weighted outer-product learning associative memory

Associative-memory neural networks with adaptive weighted outer-product learning are proposed in this paper. For the correct recall of a fundamental memory (FM), a corresponding learning weight is attached and a parameter called signal-to-noise-ratio-gain (SNRG) is devised. The sufficient conditions for the learning weights and the SNRG's are derived. It is found both empirically and theoretically that the SNRG's have their own threshold values for correct recalls of the corresponding FM's. Based on the gradient-descent approach, several algorithms are constructed to adaptively find the optimal learning weights with reference to global- or local-error measure.

Asymmetric corneal toricity and pseudokeratoconus in videokeratography

BACKGROUND

The diagnosis of asymmetric corneal toricity in video- keratography is based on the occurrence of an asymmetric bow tie pattern in the corneal map, which is usually attributed to corneal radial asymmetry but can be an artifact produced by misalignment of the videokeratograph with the corneal apex.

METHODS

This study determined whether asymmetric bow tie patterns in 16 subjects (ages 24 to 40 years with corneal toricity of 0.37 to 1.50D) could be converted to symmetric bow tie patterns by changing the alignment of the videokeratograph so that it was directed at the corneal apex.

RESULTS

In changing from regular to apex alignment the corneal map became more symmetric in 11 eyes, had no change in 3 eyes and increased in 2 eyes. No radius change could be measured centrally, but there were significant changes of greater than 1.00D in the peripheral corneal radii of 8 eyes.

CONCLUSIONS

An asymmetric or angled bow tie appearance of a corneal map suggests a decentered apex rather than corneal asymmetry and may lead to a misdiagnosis of the type or magnitude of corneal toricity, keratoconus or other corneal irregularities.

Combined-modality therapy for advanced non-small cell lung cancer: paclitaxel and thoracic irradiation

Despite advances in the modalities used to treat non-small cell lung cancer (NSCLC), the frequency of locoregional and distant relapses necessitates further enhancement of the therapeutic program. Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has demonstrated clinical efficacy against NSCLC and in vitro studies support its role as a radiation potentiator at concentrations achievable in vivo. Thus, a phase I study of weekly paclitaxel and daily concurrent thoracic radiation was conducted in patients with advanced NSCLC to determine (1) the maximum tolerated dose of paclitaxel administered on an outpatient basis for 6 consecutive weeks with daily radiation and (2) the toxicities of the paclitaxel/radiation combination. Paclitaxel was administered as a 3-hour infusion, repeated weekly for 6 weeks with the usual premedication regimen for hypersensitivity prophylaxis. The starting dose of paclitaxel was 10 mg/m2/wk, which was increased by 10 mg/m2 in successive cohorts of three new patients, as tolerated. Radiation therapy was delivered as 40 Gy in 20 fractions to the original volume with a boost of 20 Gy in 10 fractions to the primary tumor. Doses were escalated from 10 to 70 mg/m2/wk. Of the 23 patients evaluable for response, one had stage II NSCLC, four had stage IIIA, 17 had stage IIIB, and one had stage IV. Severe esophagitis (grade 4) occurred in two of the three patients treated at 70 mg/m2 and was dose limiting. One patient discontinued therapy due to hypersensitivity, two developed grade 3 neutropenia, and one developed radiation pneumonitis. With a median follow-up of 7 months, 15 of the 23 patients remain alive. Four had a complete response and 13 had a partial response, for an overall response rate of 74% (95% confidence interval, 52% to 90%). The schedule of weekly paclitaxel and daily thoracic radiation appears active in NSCLC and can be delivered safely in the outpatient setting. The principal dose-limiting toxicity is esophagitis, and the maximum tolerated dose of paclitaxel for this schedule is 60 mg/m2/wk. A phase II trial of weekly paclitaxel 60 mg/m2 and radiation has been initiated in patients with NSCLC.

Cutaneous infection with Mycobacterium abscessus

Cutaneous infection with rapidly growing mycobacteria is uncommon and diagnosis may be difficult. However, the histopathological features are distinctive and may aid diagnosis. The three pathogenic species, Mycobacterium fortuitum, M. chelonae and M. abscessus, show major differences in their antimicrobial sensitivities, and species identification is therefore important. We describe a case of infection with M. abscessus, and discuss the clinical and pathological features of such infections, and approaches to their treatment.

Tissue and tumor expression of a cell surface glycoprotein complex containing an integral membrane glycoprotein activator of p185neu

Ascites 13762 rat mammary adenocarcinoma cells contain an abundant heterodimeric cell surface glycoprotein complex. It is composed of a transmembrane subunit and a sialomucin subunit and is the product of a single gene. The transmembrane subunit has two EGF-like domains and activates the proto-oncogene receptor kinase p185neu. Southern blot comparisons of the ascites tumor and rat liver demonstrated the presence of the gene encoding the complex in normal tissues and showed an amplification of about fivefold in the ascites tumor. Polymerase chain reaction assays showed the presence of mRNA for the complex in rat brain and lung, but not in liver, pancreas, placenta, intestine, kidney, ovary and uterus. Northern blot analyses showed that the 9 kb transcript for the complex is expressed at an approximately 500-fold higher level in the ascites cells than in rat brain. Immunocytochemical studies using antiserum directed against the transmembrane subunit showed its presence in bronchial epithelium, brain ependymal and neurons of four day old animals and in the endoderm and neuronal cells of embryos. Similar immunocytochemical studies showed the presence of the transmembrane subunit in some human breast tumors. These results suggest that the gene encoding this complex is regulated in a tissue-specific manner, is overexpressed in some tumors and may play a role in tumor progression.

Clinical predictors of post-traumatic seizures in children with head trauma

STUDY OBJECTIVES

To determine the clinical characteristics associated with early post-traumatic seizures in children with head trauma. DESIGN, SETTING, AND TYPE OF PARTICIPANTS: Retrospective chart review; urban trauma center/pediatric emergency department. Trauma patients aged 3 months to 15 years given discharge diagnosis ICD-9-CM codes indicating head trauma and seen from 1988 to 1990 were eligible for the study.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 194 patients, 96% suffered blunt trauma and 53% had a loss of consciousness. Fifty-one percent of 141 computed tomography (CT) scans of the head were abnormal, most frequently demonstrating skull fractures (34%), subdural hematomas (15%), and cerebral contusions (14%). Eighteen patients (9.3%) suffered post-traumatic seizures. A loss of consciousness, a low Glasgow Coma Scale (GCS) score (3 to 8), and an abnormal CT scan were associated with post-traumatic seizures (P < .02, .001, and .02, respectively). However, only a low GCS score was predictive of post-traumatic seizures when these factors were considered simultaneously (P < .001), with 38.7% of patients with low GCS scores suffering post-traumatic seizures and 3.8% of patients with high GCS scores suffering post-traumatic seizures. In children with low GCS scores, treatment with phenytoin was associated with a decrease in post-traumatic seizures.

CONCLUSION

In the pediatric head trauma patient, a GCS score of 3 to 8 appears to be predictive of post-traumatic seizures. The data from this retrospective study are consistent with the hypothesis that prophylactic phenytoin reduces post-traumatic seizures in the pediatric head trauma patient with a low GCS score.