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1.  Quantification of increased cellularity during inflammatory demyelination 
Brain  2011;134(12):3587-3598.
Multiple sclerosis is characterized by inflammatory demyelination and irreversible axonal injury leading to permanent neurological disabilities. Diffusion tensor imaging demonstrates an improved capability over standard magnetic resonance imaging to differentiate axon from myelin pathologies. However, the increased cellularity and vasogenic oedema associated with inflammation cannot be detected or separated from axon/myelin injury by diffusion tensor imaging, limiting its clinical applications. A novel diffusion basis spectrum imaging, capable of characterizing water diffusion properties associated with axon/myelin injury and inflammation, was developed to quantitatively reveal white matter pathologies in central nervous system disorders. Tissue phantoms made of normal fixed mouse trigeminal nerves juxtaposed with and without gel were employed to demonstrate the feasibility of diffusion basis spectrum imaging to quantify baseline cellularity in the absence and presence of vasogenic oedema. Following the phantom studies, in vivo diffusion basis spectrum imaging and diffusion tensor imaging with immunohistochemistry validation were performed on the corpus callosum of cuprizone treated mice. Results demonstrate that in vivo diffusion basis spectrum imaging can effectively separate the confounding effects of increased cellularity and/or grey matter contamination, allowing successful detection of immunohistochemistry confirmed axonal injury and/or demyelination in middle and rostral corpus callosum that were missed by diffusion tensor imaging. In addition, diffusion basis spectrum imaging-derived cellularity strongly correlated with numbers of cell nuclei determined using immunohistochemistry. Our findings suggest that diffusion basis spectrum imaging has great potential to provide non-invasive biomarkers for neuroinflammation, axonal injury and demyelination coexisting in multiple sclerosis.
doi:10.1093/brain/awr307
PMCID: PMC3235568  PMID: 22171354
magnetic resonance imaging; diffusion tensor imaging; multiple tensor model; white matter injury; inflammation
2.  Diffusion Tensor Imaging in Acute Optic Neuropathies 
Archives of neurology  2011;69(1):65-71.
Objective
To evaluate directional diffusivities within the optic nerve in a first event of acute optic neuritis to determine whether decreased axial diffusivity (AD) would predict 6-month visual outcome and optic nerve integrity measures.
Design
Cohort study.
Setting
Academic multiple sclerosis center.
Patients
Referred sample of 25 individuals who presented within 31 days after acute visual symptoms consistent with optic neuritis. Visits were scheduled at baseline, 2 weeks, and 1, 3, 6, and 12 months.
Main Outcome Measures
Visual acuity, contrast sensitivity, visual evoked potentials (VEPs), and thickness of the retinal nerve fiber layer (RNFL).
Results
An incomplete 6-month visual recovery was associated with a lower baseline AD (1.50 μm2/ms [95% confidence interval {CI}, 1.36–1.64 μm2/ms for incomplete recovery vs 1.75 μm2/ms [95% CI, 1.67–1.83 μm2/ms] for complete recovery). Odds of complete recovery decreased by 53% (95% CI, 27%–70%) for every 0.1-unit decrease in baseline AD. A lower baseline AD correlated with worse 6-month visual outcomes in visual acuity (r=0.40, P=.03), contrast sensitivity (r=0.41, P=.02), VEP amplitude (r=0.55, P<.01), VEP latency (r=−0.38, P=.04), and RNFL thickness (r=0.53, P=.02). Radial diffusivity increased between months 1 and 3 to become higher in those with incomplete recovery at 12 months than in those with complete recovery (1.45 μm2/ms [95% CI, 1.31–1.59 μm2/ms] vs 1.19 μm2/ms [95% CI, 1.10–1.28 μm2/ms]).
Conclusions
Decreased AD in acute optic neuritis was associated with a worse 6-month visual outcome and correlated with VEP and RNFL measures of axon and myelin injury. Axial diffusivity may serve as a marker of axon injury in acute white matter injury.
doi:10.1001/archneurol.2011.243
PMCID: PMC3489058  PMID: 21911658
3.  Radial Diffusivity Predicts Demyelination in ex-vivo Multiple Sclerosis Spinal Cords 
NeuroImage  2011;55(4):1454-1460.
Objective
Correlation of diffusion tensor imaging (DTI) with histochemical staining for demyelination and axonal damage in multiple sclerosis (MS) ex vivo human cervical spinal cords.
Background
In MS, demyelination, axonal degeneration, and inflammation contribute to disease pathogenesis to variable degrees. Based upon in vivo animal studies with acute injury and histopathologic correlation, we hypothesized that DTI can differentiate between axonal and myelin pathologies within humans.
Methods
DTI was performed at 4.7 Tesla on 9 MS and 5 normal control fixed cervical spinal cord blocks following autopsy. Sections were then stained for Luxol fast blue (LFB), Bielschowsky silver, and hematoxylin and eosin (H&E). Regions of interest (ROIs) were graded semi-quantitatively as normal myelination, mild (<50%) demyelination, or moderate-severe (>50%) demyelination. Corresponding axonal counts were manually determined on Bielschowsky silver. ROIs were mapped to co-registered DTI parameter slices. DTI parameters evaluated included standard quantitative assessments of apparent diffusion coefficient (ADC), relative anisotropy (RA), axial diffusivity and radial diffusivity. Statistical correlations were made between histochemical gradings and DTI parameters using linear mixed models. Results: Within ROIs in MS subjects, increased radial diffusivity distinguished worsening severities of demyelination. Relative anisotropy was decreased in the setting of moderate-severe demyelination compared to normal areas and areas of mild demyelination. Radial diffusivity, ADC, and RA became increasingly altered within quartiles of worsening axonal counts. Axial diffusivity did not correlate with axonal density (p=0.091).
Conclusions
Increased radial diffusivity can serve as a surrogate for demyelination. However, radial diffusivity was also altered with axon injury, suggesting that this measure is not pathologically specific within chronic human MS tissue. We propose that radial diffusivity can serve as a marker of overall tissue integrity within chronic MS lesions. This study provides pathologic foundation for on-going in vivo DTI studies in MS.
doi:10.1016/j.neuroimage.2011.01.007
PMCID: PMC3062747  PMID: 21238597
Multiple Sclerosis; Diffusion Tensor Imaging; Post mortum; Spinal cord
4.  PSYCHOLOGICAL FACTORS RELATED TO DELAY IN CONSULTATION FOR CANCER SYMPTOMS 
Psycho-Oncology  2005;14(5):339-350.
SUMMARY
This research investigated psychological characteristics associated with delay in seeking help for symptoms of rectal cancer. Sixty nine subjects reconstructed pivotal events beginning with symptom onset and ending with medical consultation, and completed the Temperament and Character Inventory (TCI) and the State-Trait Anxiety Inventory (STAI). The mean delay time was around 6 months, with about 1 out of 6 subjects waiting one year or more. Subjects estimated the lengths of two sequential segments of total time to consultation: (1) Symptom Appraisal time (from symptom onset to recognition of possible seriousness), and (2) Action Appraisal time (from recognition of seriousness to medical consultation). Symptom Appraisal time accounted for over two-thirds of total time and was associated with low scores on the TCI Harm Avoidance scale (TCI-HA), indicating dispositional insensitivity to threat, and marginally associated with less education and younger age. Action Appraisal time was not associated with any demographic or psychological variables. Low TCI-HA scores were also associated with lower likelihood of previous cancer screening, and with better judgments of premorbid health. Low STAI Trait scores were associated with better judgments of premorbid health and fewer doctor visits. Results are discussed regarding the importance of understanding dispositional characteristics related to health behavior.
doi:10.1002/pon.850
PMCID: PMC3320717  PMID: 15386764
5.  Thymidylate Synthase Genotype-Directed Neoadjuvant Chemoradiation for Patients With Rectal Adenocarcinoma 
Journal of Clinical Oncology  2011;29(7):875-883.
Purpose
Downstaging (DS) of rectal cancers is achieved in approximately 45% of patients with neoadjuvant fluorouracil (FU) -based chemoradiotherapy (CRT). Polymorphisms in the thymidylate synthase gene (TYMS) had previously defined two risk groups associated with disparate tumor DS rates (60% v 22%). We conducted a prospective single-institution phase II study using TYMS genotyping to direct neoadjuvant CRT for patients with rectal cancer.
Patients and Methods
Patients with T3/T4, N0-2, M0-1 rectal adenocarcinoma were evaluated for germline TYMS genotyping. Patients with TYMS *2/*2, *2/*3, or *2/*4 (good risk) were treated with standard chemoradiotherapy using infusional FU at 225 mg/m2/d. Patients with TYMS *3/*3 or *3/*4 (poor risk) were treated with FU/RT plus weekly intravenous irinotecan at 50 mg/m2. The primary end point was pathologic DS. Secondary end points included complete tumor response (ypT0), toxicity, recurrence rates, and overall survival.
Results
Overall, 135 patients were enrolled, of whom 27.4% (37 of 135) were considered poor risk. The prespecified statistical goals were achieved, with DS and ypT0 rates reaching 64.4% and 20% for good-risk and 64.5% and 42% for poor-risk patients, respectively.
Conclusion
To our knowledge, this is the first study to prospectively use TYMS genotyping to direct neoadjuvant CRT in patients with rectal cancer. High rates of DS and ypT0 were achieved among both risk groups when personalized treatment was based on TYMS genotype. These results are encouraging, and further evaluation of this genotype-based strategy using a randomized study design for locally advanced rectal cancer is warranted.
doi:10.1200/JCO.2010.32.3212
PMCID: PMC3068061  PMID: 21205745
7.  Rostro-Caudal Analysis of Corpus Callosum Demyelination and Axon Damage Across Disease Stages Refines Diffusion Tensor Imaging Correlations with Pathological Features 
Non-invasive assessment of the progression of axon damage is important for evaluating disease progression and developing neuroprotective interventions in multiple sclerosis (MS) patients. We examined the cellular responses correlated with diffusion tensor imaging (DTI)-derived axial (λ||) and radial (λ⊥) diffusivity values throughout acute (4 weeks) and chronic (12 weeks) stages of demyelination and after 6 weeks of recovery using the cuprizone demyelination of the corpus callosum model in C57BL/6 and Thy1-YFP-16 mice. The rostro-caudal progression of pathologic alterations in the corpus callosum enabled spatially and temporally defined correlations of pathological features with DTI measurements. During acute demyelination, microglial/macrophage activation was most extensive and axons exhibited swellings, neurofilament dephosphorylation, and reduced diameters. Axial diffusivity values decreased in the acute phase but did not correlate with axonal atrophy during chronic demyelination. In contrast, radial diffusivity increased with the progression of demyelination but did not correlate with myelin loss or astrogliosis. Unlike other animals models with progressive neurodegeneration and axon loss, the acute axon damage did not progress to discontinuity or loss of axons even after a period of chronic demyelination. Correlations of reversible axon pathology, demyelination, microglia/macrophage activation, and astrogliosis with regional axial and radial diffusivity measurements will facilitate the clinical application of DTI in MS patients.
doi:10.1097/NEN.0b013e3181e3de90
PMCID: PMC2901930  PMID: 20535036
Astrogliosis; Axon damage; Corpus callosum; Cuprizone; Demyelination; Diffusion tensor imaging; Microglia activation
8.  Diffusion Tensor Imaging at 3 Hours after Traumatic Spinal Cord Injury Predicts Long-Term Locomotor Recovery 
Journal of Neurotrauma  2010;27(3):587-598.
Abstract
Accurate diagnosis of spinal cord injury (SCI) severity must be achieved before highly aggressive experimental therapies can be tested responsibly in the early phases after trauma. These studies demonstrate for the first time that axial diffusivity (λ||), derived from diffusion tensor imaging (DTI) within 3 h after SCI, accurately predicts long-term locomotor behavioral recovery in mice. Female C57BL/6 mice underwent sham laminectomy or graded contusive spinal cord injuries at the T9 vertebral level (5 groups, n = 8 for each group). In-vivo DTI examinations were performed immediately after SCI. Longitudinal measurements of hindlimb locomotor recovery were obtained using the Basso mouse scale (BMS). Injured and spared regions of ventrolateral white matter (VLWM) were reliably separated in the hyperacute phase by threshold segmentation. Measurements of λ|| were compared with histology in the hyperacute phase and 14 days after injury. The spared normal VLWM determined by hyperacute λ|| and 14-day histology correlated well (r = 0.95). A strong correlation between hindlimb locomotor function recovery and λ||-determined spared normal VLWM was also observed. The odds of significant locomotor recovery increased by 18% with each 1% increase in normal VLWM measured in the hyperacute phase (odds ratio = 1.18, p = 0.037). The capability of measuring subclinical changes in spinal cord physiology and murine genetic advantages offer an early window into the basic mechanisms of SCI that was not previously possible. Although significant obstacles must still be overcome to derive similar data in human patients, the path to clinical translation is foreseeable and achievable.
doi:10.1089/neu.2009.1063
PMCID: PMC2867549  PMID: 20001686
axial diffusion; diffusion tensor imaging; hyperacute; magnetic resonance imaging; recovery; spinal cord injury
9.  Changes in B and T lymphocytes and chemokines with rituximab treatment in multiple sclerosis 
Archives of neurology  2010;67(6):707-714.
Background
B cells are implicated in the pathogenesis of multiple sclerosis (MS). A beneficial effect of B cell depletion using rituximab has been shown, but the complete mechanism of action for this drug is unclear.
Objective
To determine the relationship between T cells, B cells, and changes in CSF chemokines with rituximab, a monoclonal antibody that targets CD20.
Design
Phase II trial of rituximab as an add-on therapy.
Setting
The John L. Multiple Sclerosis Center, Washington University, St. Louis, Missouri.
Patients
Thirty relapsing-remitting MS subjects with clinical and MRI activity despite treatment with an immunomodulatory drug received four weekly doses of 375mg/m2 rituximab.
Main Outcome Measures
Lumbar puncture was performed before and after rituximab infusions in 26 subjects. CSF B and T lymphocytes were enumerated by flow cytometry, and chemoattractants were measured by ELISA.
Results
After rituximab administration, CSF B cells were decreased or undetectable in all subjects and CSF T cells were reduced in 81% of subjects. The mean reduction in CSF cellularity was 95% for B cells and 50% for T cells. After rituximab infusion, CSF CXCL13 and CCL19 decreased (P= 0.002, P=0.03, respectively). The proportional decline in CSF T cells correlated with the proportional decrease in CXCL13 (r=0.45;P=0.03), suggesting a possible relationship. CSF IgG index, IgG concentration, and oligoclonal band number were unchanged following treatment.
Conclusions
B cells are critical for T cell trafficking into the CNS in MS patients, and may alter T cell trafficking by influencing chemokine production within the CNS.
doi:10.1001/archneurol.2010.99
PMCID: PMC2918395  PMID: 20558389
10.  Acute Asthma Management by a Pediatric After-Hours Call Center 
Telemedicine Journal and e-Health  2009;15(6):538-545.
Abstract
To describe an asthma management protocol used in a nurse-staffed pediatric After-Hours Call Center (AHCC) that incorporates severity-based home treatment recommendations and follow-up call assessments. Call records for asthma advice from January 1, 2004 to June 30, 2004 were identified retrospectively and reviewed. Descriptive statistics were used to report patient demographics, frequencies of symptom severity zones (Red, Yellow, or Green) at initial calls, frequencies of call dispositions designating care advice provided (including home treatment recommendations and seeking emergency department [ED] care), and changes in severity zones between initial calls and follow-up calls when nurses reassessed patients after recommended home treatment. During the study period, 3,632 asthma calls (2,439 initial; 1,193 follow-up) were managed by AHCC nurses. Initial calls were classified mostly as Red (28%) or Yellow (42%) severity zones; 27% were Green zone and 3% could not be categorized. Fifty-two percent of initial calls with Red or Yellow severity zones involved home treatment recommendations; 50% of those Red zone and 63% of those Yellow zone calls had improved severity zones at follow-up call assessments. Twenty-eight percent of patients with home treatment recommendations were referred to the ED at the time of follow-up call nurse reassessment. This telephone-based nurse-staffed pediatric acute asthma management protocol includes provision of severity-based home treatment recommendations and follow-up assessments, and improved symptoms for many children with acute exacerbations. This protocol may also be successful in other locations and may improve outcomes, such as reduction in ED visits.
doi:10.1089/tmj.2009.0005
PMCID: PMC2956520  PMID: 19566399
asthma; child; call center
11.  Trait anxiety as an independent predictor of poor health-related quality of life and post-traumatic stress symptoms in rectal cancer 
British journal of health psychology  2009;14(Pt 4):701-715.
Objectives
To determine the influence of trait anxiety on patient reports of health-related quality of life (HRQoL) and post-traumatic stress symptoms (PTSS) in a sample of rectal cancer survivors.
Design
Eighty patients who had been diagnosed with rectal cancer were assessed at two points in time in a longitudinal study.
Methods
At Time 1, soon after initial treatment, participants completed the State-Trait Anxiety Inventory and the Temperament and Character Inventory Harm Avoidance scale, which were combined into a composite measure of trait anxiety. At Time 2, 2-5 years following Time 1, participants were assessed for HRQoL using the Functional Assessment of Cancer Therapy-Colorectal scale (FACT-C) and for PTSS using the Impact of Event Scale-Revised (IES-R).
Results
HRQoL and PTSS were generally favourable on average, although many of the patients reported faring poorly. Higher levels of trait anxiety were predictive of poorer scores on all of the FACT-C and the IES-R total and subscale measures. More severe faecal incontinence was associated with poorer scores on the FACT Emotional well-being subscale, the FACT-Colorectal Cancer Scale, and all of the IES-R scales. Males were more likely than females to have poorer scores on the FACT Social well-being subscale, and those patients who were further out from active treatment had more favourable scores on the FACT-Colorectal Cancer Scale. The presence of a colostomy did not impact HRQoL or PTSS.
Conclusion
Trait anxiety had a significant influence on HRQoL and PTSS several years following diagnosis and treatment of rectal cancer.
doi:10.1348/135910708X400462
PMCID: PMC2756319  PMID: 19171084
12.  Sex differences in responding to rectal cancer symptoms 
Psychology & health  2008;23(8):935-944.
Many people who develop cancer symptoms wait inordinate amounts of time before seeking medical attention. Studies have found that symptom appraisal time - the time that passes before the individual concludes that their symptoms could be serious - accounts for most of the total delay time across subjects. It is thus important to understand the individual characteristics associated with slow recognition of dangerous symptoms. In this study, 62 patients (38 males) recently diagnosed with rectal cancer answered questions regarding the development of symptoms as well as their decisions and behaviors prior to seeking help. One subgroup of patients - males with the lowest scores on a measure of trait anxiety - took significantly longer to recognize the seriousness of their symptoms as compared to all other patients. This finding is discussed in the context of recent studies where the interaction of sex and negative affect is related to symptom reporting and other health-related behaviors.
doi:10.1080/08870440701657494
PMCID: PMC2744129  PMID: 19759846
Harm avoidance; patient delay; rectal cancer; sex differences; symptom appraisal; trait anxiety
13.  Isolation and Molecular Profiling of Bone Marrow Micrometastases Identifies TWIST1 as a Marker of Early Tumor Relapse in Breast Cancer Patients 
Purpose
Micrometastatic cells detected in the bone marrow have prognostic significance in breast cancer. These cells are heterogeneous and likely do not exhibit uniform biological behavior. To understand the molecular diversity of disseminated cancer cells that reside in bone marrow, we enriched this cell population and did global gene expression profiling in the context of a prospective clinical trial involving women with clinical stage II/III breast cancer undergoing neoadjuvant chemotherapy.
Experimental Design
Enrichment of TACSTD1 (EpCAM)-expressing cells from bone marrow of breast cancer patients was achieved using immunomagnetic beads. Gene expression profiles were compared between enriched cell populations and whole bone marrow from 5 normal volunteers and 23 breast cancer patients after neoadjuvant chemotherapy treatment. Enriched cells from bone marrow samples of breast cancer patients before treatment or at 1 year follow-up were also analyzed (total of 87 data sets). The expression of transcripts specifically detected in enriched cell populations from breast cancer patients was correlated with 1-year clinical outcome using quantitative reverse transcription-PCR in an independent cohort of bone marrow samples.
Results
Analysis of EpCAM-enriched bone marrow cells revealed specific expression of a sub-group of transcripts, including the metastasis regulator, TWIST1. Most transcripts identified, including TWIST1, were not expressed in enriched populations of bone marrow from normal volunteers, suggesting that this expression profile reflects a signature of breast cancer bone marrow micrometastases that persist after chemotherapy. In an independent set of bone marrow samples obtained before any treatment, TWIST1 expression correlated with early disease relapse.
Conclusions
Disseminated breast cancer cells present in bone marrow after chemotherapy possess unique transcriptional signatures. Genes whose expression is overrepresented in these cell populations, such as TWIST1, may prove to be excellent markers of early distant relapse in breast cancer patients.
doi:10.1158/1078-0432.CCR-07-0024
PMCID: PMC2680916  PMID: 17785550
14.  Selective sigma-2 ligands preferentially bind to pancreatic adenocarcinomas: applications in diagnostic imaging and therapy 
Molecular Cancer  2007;6:48.
Background
Resistance to modern adjuvant treatment is in part due to the failure of programmed cell death. Therefore the molecules that execute the apoptotic program are potential targets for the development of anti-cancer therapeutics. The sigma-2 receptor has been found to be over-expressed in some types of malignant tumors, and, recently, small molecule ligands to the sigma-2 receptor were found to induce cancer cell apoptosis.
Results
The sigma-2 receptor was expressed at high levels in both human and murine pancreas cancer cell lines, with minimal or limited expression in normal tissues, including: brain, kidney, liver, lung, pancreas and spleen. Micro-PET imaging was used to demonstrate that the sigma-2 receptor was preferentially expressed in tumor as opposed to normal tissues in pancreas tumor allograft-bearing mice. Two structurally distinct sigma-2 receptor ligands, SV119 and WC26, were found to induce apoptosis to mice and human pancreatic cancer cells in vitro and in vivo. Sigma-2 receptor ligands induced apoptosis in a dose dependent fashion in all pancreatic cell lines tested. At the highest dose tested (10 μM), all sigma-2 receptor ligands induced 10–20% apoptosis in all pancreatic cancer cell lines tested (p < 0.05). In pancreas tumor allograft-bearing mice, a single bolus dose of WC26 caused approximately 50% apoptosis in the tumor compared to no appreciable apoptosis in tumor-bearing, vehicle-injected control animals (p < 0.0001). WC26 significantly slowed tumor growth after a 5 day treatment compared to vehicle-injected control animals (p < 0.0001) and blood chemistry panels suggested that there is minimal peripheral toxicity.
Conclusion
We demonstrate a novel therapeutic strategy that induces a significant increase in pancreas cancer cell death. This strategy highlights a new potential target for the treatment of pancreas cancer, which has little in the way of effective treatments.
doi:10.1186/1476-4598-6-48
PMCID: PMC1939854  PMID: 17631687

Results 1-14 (14)