Attached are summaries of presentations at the resent Autism Research Institute’s Think Tank. The same was held in Baltimore from April 12-14, 2013.In-keeping with the spirit of the Think Tank I asked permission from each participant before posting. Those who did not provide permission have not been included. I will add some photographs of the event at a later date.
Richard Deth, PhD
Autism Research Update
Topics covered included: 1. Lessons from autism in Oman: Vitamin deficiency and elevated heavy metals. 2. Methionine synthase status in postmortem brain during autism and aging. 3. Global regulation of metabolism by redox-sensitive methylation reactions. 4. Genome-wide epigenetic effects of casein and glutenderived opiate peptides. 5. D4 dopamine receptor regulation of gamma frequency synchronization of neural networks.
Richard Deth is a professor of pharmacology at Northeastern University in Boston, where his research is focused on the roles of redox and methylation in autism and D4-type dopamine-receptor signaling related to attention. His lab first showed that neurodevelopmental toxins, including thimerosal, inhibit the enzyme methionine synthase and block synthesis of methyl-B12. He is the author of Molecular Origins of Human Attention: The Dopamine-Folate Connec-tion.
Does high brain ammonia cause autism? Is glutamine a safe remedy? Smoking guns and compelling arguments – res ipsa loquitur
Blood ammonia is often high in children with autistic disorders, yet curiously (paradoxically?) blood glutamine is consistently low, brain glutamine often low. Furthermore, children with in-born urea cycle disorders (high brain ammonia and glutamine) rarely show autistic behavior. This might mean ammonia doesn’t cause autistic behavior – but might also mean high brain glutamine prevents it. Another ‘smoking gun’ is the striking benefit of infectious fever, which often relieves autistic behavior (often dramatically) and rarely aggravates. Loss of appetite with fever rapidly depletes glycogen stores, releasing glutamine and other amino acids from skeletal muscles to blood as substrate for glucose. Supplemental glutamine heals intestines in children with ASD, and has improved behavior, but some practitioners are understandably wary of the ammonia and glutamate that glutamine generates. Glutamine released from muscles, however, is metabolized by the intestines like ingested glutamine. If glutamine released by fever rarely aggravates autistic behavior, why would supplemental glutamine? Low blood glutamine may reveal impaired conversion of ammonia to glutamine in muscles, liver, and brain; low brain gluta-mine may reveal impaired astrocyte glutamate transport. Salt cravings may reveal stress-induced subclinical low blood sodium (and impairment of the sodium pump) impairing astrocyte glutamate transport and releasing brain osmolytes taurine and glutamine.
Peter Good is an independent researcher from central Oregon with ASD. Self-taught in the medical sciences (~1500 pdfs), he studied multiple sclerosis 30 years, then noticed parallels between MS and autism. His published papers and letters are online at http://www.autismstudies.info.
Richard Frye, MD, PhD
Maladaptive Mitochondrial Response to Oxidative Challenge in Immune Cells from Au-tism Spectrum Disorder Children
There is increasing recognition that mitochondrial dysfunction is associated with autism spectrum disorders (ASD), but less attention has been paid to the etiology of the mitochondrial dysfunction and how mitochondrial dysfunction interacts with other physiological disturbances associated ASD such as oxidative stress. Reserve capacity is a measure of the ability of the mitochondria to respond to physiological stress. In this study, for the first time, we demonstrate that immune cells derived from children with ASD have altered mitochondrial reserve capacity at baseline and when exposed to physiological levels of reactive oxygen species (ROS). These abnormalities, which include abnormally high reserve capacity at baseline and a precipitous depletion of reserve capacity when challenged with ROS, were demonstrated in a significant subgroup of lymphoblastoid cell lines (LCLs) and peripheral blood mononuclear cells (PBMCs) derived from children with ASD. In the subgroup of LCLs derived from children with ASD, these abnormalities were attenuated by pretreatment with 48-hours of N-acetyl-cysteine, a glutathione precursor, suggesting a role for abnormal glutathione metabolism as a cause of these mitochondrial abnormalities. Next, a subgroup of PBMCs derived from children with ASD was identified with higher baseline reserve capacity that was significantly depleted with ROS challenge. This subgroup was found to manifest significantly lower scores of socialization, daily living skills and the adaptive behavior composite on the Vineland Adaptive Behavior Scale. This study suggests that a significant subgroup of ASD children have alterations in mitochondrial function which may represent an adaptive response to an abnormally oxidized microenvironment. Importantly, this study suggests the ability of the mitochondria to adapt to alterations in its microenvironment may have developmental consequences.
Dr Richard Frye, MD, Ph.D. is the Director of Autism Research at Arkansas Children’s Hospital in Little Rock, AR. Dr Frye is a well-recognized expert in the diagnosis and treatment of autism and other developmental disorders. Dr. Frye has a broad background including specific training in neurodevelopmental disorders, physiology, psychology and biostatistics. He is fellowship trained in Behavioral Neurology and Psychology and has clinical expertise in the assessment, diagnosis and treatment of children with ASD. He has completed several three clinical studies related to autism, including studies on tetrahydrobiopterin, mitochondrial disease, the folate receptor alpha autoantibody and leucovorin treatment in autistic children with folate receptor alpha autoantibodies. As Director of Autism Research at the Arkansas Children’s Hospital he has developed an integrated program that includes a multispecialty clinic, a translational research program focusing on biomarkers and clinical-trials, and a basic science program focusing on mitochondrial and redox metabolism.
Dan Rossignol, MD / Richard Frye, MD, PhD
Cerebral folate autoantibodies and autism
Cerebral folate deficiency (CFD) syndrome is a neurodevelopmental disorder typically caused by folate receptor autoantibodies (FRAs) that interfere with folate transport across the blood– brain barrier. Autism spectrum disorders (ASDs) and improvements in ASD symptoms with leucovorin (folinic acid) treatment have been reported in some children with CFD. In children with ASD, the prevalence of FRAs and the response to leucovorin in FRA-positive children has not been systematically investigated. In this study, serum FRA concentrations were measured in 93 children with ASD and a high prevalence (75.3%) of FRAs was found. In 16 children, the con-centration of blocking FRA significantly correlated with cerebrospinal fluid 5 methyltetrahydrofolate concentrations, which were below the normative mean in every case. Since the folate receptor is also located on thyroid cells, a potential relationship between a marker of thyroid function (TSH) and folate receptor autoantibody concentrations was examined and a significant relationship was found. Children with FRAs were treated with oral leucovorin calcium (2mg/kg/day; maximum 50mg per day). Treatment response was measured and compared with a wait-list control group. Compared with controls, significantly higher improvement ratings were observed in treated children over a mean period of 4 months in verbal communication, receptive and expressive language, attention and stereotypical behavior. Approximately one-third of treated children demonstrated moderate to much improvement. The incidence of adverse effects was low. This study suggests that FRAs may be important in ASD and that FRA-positive children with ASD may benefit from leucovorin calcium treatment. Given these results, empirical treatment with leucovorin calcium may be a reasonable and non-invasive approach in FRA-positive children with ASD. Additional studies of folate receptor autoimmunity and leucovorin calcium treatment in children with ASD are warranted.
Dr. Rossignol received his Doctorate of Medicine at the Medical College of Virginia and completed his residency in family medicine at the University of Virginia. Coming from an academic background, Dr. Rossignol searched the medical literature looking for a solution after both of his children were diagnosed with autism. He has made it his mission to research and publish in autism. In the last 6 years, he has 31 publications and 3 book chapters concerning autism and related conditions.
Jill James, PhD
Evidence of oxidative and epigenetic alterations in the autism brain
In previous studies, we reported that children with ASD exhibit a decrease in glutathione redox capacity in plasma, lymphoblastoid cells and primary immune cells associated with mitochondrial abnormalities and markers of protein and DNA damage. Low SAM/SAH in plasma was associated with global DNA hypomethylation in lymphocytes. More recently, we have extended our investigation of redox and epigenetic abnormalities to the autism brain. Our examination of redox abnormalities in the cerebellum and temporal cortex revealed that decreased GSH/GSSG redox/antioxidant capacity is indeed present in the autism brain. In addition, low redox capacity was associated with functional consequence as reflected by evidence of chronic inflammation, increased mitochondrial superoxide production as well as oxidative protein and DNA damage. These results in the ASD brain parallel observations in the periphery suggesting that that a pro-oxidant environment and oxidative stress are pervasive and systemic in autism and that peripheral biomarkers may be a convenient surrogate for redox abnormalities in the brain. In a separate study, we initiated a comprehensive evaluation of epigenetic alterations in the autism cerebellum by evaluating promoter region DNA methylation, histone modifications and gene expression of Engrailed-2 (EN-2), a developmentally regulated homeobox gene relevant to autism. Counter to expectations, global DNA and promoter region hypermethylation were associated with an in-crease in protein and gene expression that may be explained by alterations in histone methylation. These epigenetic observations are opposite to those observed in peripheral cells suggesting that epigenetic alterations are tissue-specific and cannot be extrapolated to the brain. Together, the results suggest that the normal EN-2 down-regulation that signals Purkinje cell maturation during perinatal development may not have occurred in some individuals with autism and that the abnormal postnatal persistence of EN-2 over-expression may contribute to autism cerebellar abnormalities. Dr. James will end her presentation with late-breaking evidence that transmethylation and transsulfuration metabolites are abnormal in ~20% of pregnant high risk mothers who already have one child with autism.
Jill James is a Professor in the Department of Pediatrics, Section of Developmental Disabilities, and the Director of the Metabolic Genomics Laboratory at the Arkansas Children’s Hospital Re-search Institute. She has published over 130 peer-reviewed papers and recently received the American Society for Nutritional Sciences award for innovative research contributing to the understanding of human nutrition. She is currently funded by a 5-year NIH grant entitled “Metabolic biomarkers of autism: predictive potential and genetic susceptibility,” a grant for the Department of Defense entitled “Autism as a vulnerability phenotype,” and a grant from Autism Speaks for the Arkansas Autism Treatment Network.
Irva Hertz-Picciotto, PhD, MPH
Current State-of-the-Science on Environmental Factors in Autism
The causes of autism spectrum disorders (ASD) are diverse and include both genetic and non-inherited factors or exposures. Although a major focus of research has been the hunt for ASD genes, which has uncovered links to rare syndromes and even some potential common mechanisms for perturbed brain development, the recent period has also witnessed a rapid emergence of clues about environmental contributions. This presentation will review the state-of-the-science on a wide array of modifiable factors: pesticides, metals, air pollution, vinyl flooring, maternal nutrition, metabolic conditions and acute illnesses. These discoveries and their replication are critical to the development of intervention strategies that can reduce risk entirely or lessen the severity of the symptoms. In the context of research approaches, several other concepts will be discussed: the multifactorial nature of autism causality, critical time windows, and the relation-ship of genetic and environmental factors.
Dr. Hertz-Picciotto, Professor at the University of California Davis MIND Institute is an environmental epidemiologist with over 250 scientific publications addressing environmental exposures, including metals, pesticides, air contaminants and endocrine disrupting compounds, their interactions with nutrition, and their effects on pregnancy, the newborn, and child development. She is Director for CHARGE (Childhood Autism Risk from Genes and Environment), the first large, comprehensive population-based study of environmental factors in autism, and MARBLES (Markers of Autism Risk in Babies – Learning Early Signs) to search for early markers that will predict autism, starting in pregnancy. She has served on scientific advisory panels for the U.S. Environmental Protection Agency, the National Toxicology Program, the California Air Re-sources Board and Proposition 65 committee, and the NIH Interagency Coordinating Committee on Autism Research. She has been President of two major professional epidemiology societies, and chaired two National Academy of Sciences/Institute of Medicine Panels: Agent Orange and Vietnam Veterans, and more recently, Breast Cancer and the Environment. In 2011, she received the Goldsmith Lifetime Achievement Award from the International Society for Environ-mental Epidemiology.
J. Bruce German, PhD
As life sciences interrogate organisms in genomic detail, lactation and its remarkable product, milk, provide unique insight into the evolution of animals and their food. The natural colonization of breast-fed infants is a complex interplay between the transfer from maternal stores of unique strains of bifidobacteria (notably Bifidobacteria longum biovar infantis) and the provision of highly complex oligosaccharides via milk. The undigestible, complex human milk oligosaccharides (HMOs) are either not fermentable by other bacteria or are very poor substrates for other bacteria. At the same time, bifidobacteria have evolved specialized transporters and metabolic enzymes to consume with high efficiency and specificity the oligosaccharides from human milk. It is this fermentation selectivity that is responsible for the enrichment of bifidobacteria in the gastrointestinal tract of neonates. The process of microbiota transition in the breast-fed infant is instructive. The initial colonization immediately after birth is diverse and highly dynamic, and oligosaccharides in milk are typically excreted unmodified. Then B. infantis and other cognate HMO-specialized bifidobacteria begin to increase in concentration and become the dominant bacteria within the infant’s microbiota population simultaneously with the disappearance of the milk oligosaccharides from the intestine. Notably this enrichment in B. infantis persists through-out lactation and then diminishes to ostensibly undetectable levels on cessation of breast feeding and the consumption of solid food or infant formula (both lacking MOs).
Research from the UC Davis program has characterized the mammalian milk oligosaccharides and annotated the genomes of bifidobacterial strains including Bifidobacterium longum subsp. infantis (B. infantis) and B. bifidum, two bacterial species commonly found in the feces of breast-fed infants. Genomic analysis of these species has revealed unique gene clusters linked to HMO metabolism. Importantly, more recent research has documented the existence of complex milk oligosaccharides in other mammalian milks and industrially accessible in the whey of bovine milk cheese making. The UC Davis program has developed industrial technologies to isolate these molecules from commercial product streams where they occur. The metric tons of whey available as industrial food material makes it possible to propose the use of whey as a commer-cially viable resource of complex, selective mammalian oligosaccharides for a wide variety of applications in at-risk subjects, potentially including those with neurological developmental dis-orders.
J. Bruce German is the Director of the Foods for Health Institute, and a Professor in the Department of Food Science & Technology at the University of California, Davis. He holds a B.S. in Biology and an M.S. in Plant Biochemistry from the University of Western Ontario, Canada, and a Ph.D. in Food Chemistry from Cornell University. In addition to investigating the importance of milk, he is interested in the lipid or fatty component responsible for much of the metabolic and sensory attributes of food, and how the consumption of specific classes of fats is implicated in the etiology of many human chronic diseases.
Eric Hollander, MD
Personalized Experimental Therapeutics of Inflammation
We have examined the underlying mechanisms of a fever response and involvement of the immune-inflammatory system in ASD via four approaches: 1. Oxytocin vs placebo in ASD: (oxytocin not only has potent effects on social cognition and lower order repetitive behaviors but also has effects on obesity and wound healing; clinical response may be magnified in syndromal forms of ASD – tuberous sclerosis and Prader Willi Syndrome), 2. Hyperthermia: children with ASD are compared at temperatures of 102 degrees vs 98 degrees on clinical measures, biomarkers, and gene expression profiling, 3. LC/NE function as an outcome of maternal stress is examined by a milnacipran vs placebo trial of ASD, 4. TSO (trichura suis ova; a helminth) vs placebo is examined in adult ASD on clinical measures and biomarkers.
Dr. Hollander is Director of the Autism and Obsessive Compulsive Spectrum Program and Clinical Professor of Psychiatry and Behavioral Sciences at the Albert Einstein College of Medicine and the Montefiore Medical Center. He is also Director of the Spectrum Neuroscience and Treatment Institute, and Chair of the Advisory Council, ICare4Autism. Formerly, he has served as the Esther and Joseph Klingenstein Professor and Chairman of Psychiatry, Director of the Seaver and Greater NY Autism Center of Excellence, and Director of the Compulsive, Impulsive and Anxiety Disorders Program at Mount Sinai School of Medicine. Prior to then, he was Associate Professor of Psychiatry and Director of the Compulsive and Impulsive Disorders Program at Columbia University College of Physicians and Surgeons.
Harland Winter, MD
The co-occurrence of gastrointestinal (GI) issues with autism was noted in the original description of autism by Leo Kanner in 1943, who described feeding or dietary issues as common. Since that time, healthcare providers have tried to identify the causes of perceived abdominal discomfort in children affected by autism. A recent consensus report concludes that most children with autism do not have a unique gastrointestinal disorder caused by or causing autism, but rather have common childhood GI conditions that may go unrecognized or undertreated because the children’s’ social interaction and communication impairments contribute to an atypical presentation of these common conditions. We hope to understand the relationship of the intestinal microbial ecosystem to the development of GI dysfunction and problem behaviors in children with autism spectrum disorders (ASD).
Autism is a disease that begins in early childhood with the loss or failure to acquire developmental milestones at the same time the microbial community is being established in the gut. Neurologic, genetic, and metabolic associations with autism have been identified for small groups of children, but triggering events are not known. Many parents have identified clinical improvement in behavior with restricted diets and antibiotics supporting the belief that there is relation-ship between the brain and the gut. Recent advances in sequencing technology have enabled investigators to evaluate microbial diversity and characterize the intestinal microbiome. Studies in children with ASD have demonstrated that Desulfovibrio is more common in the stool of children with ASD compared with controls; whereas, other studies have reported increased Bacteroides vulgatus in the stool and Sutterella in the mucosa of children with ASD and GI symptoms. In one report, co-authored, the mucosal expression of some brush border enzymes and transporters were associated with dysbiosis characterized by decreases in Bacteroidetes, increases in Betaproteobacteria, and increases in the ratio of Firmicutes to Bacteroidetes. Understanding this ecosystem and its impact on the host epigenome and transcriptome in a patient population with gastrointestinal and behavioral problems is likely to provide new insight into the role of the GI tract in the pathogenesis of ASD and lead to innovative therapeutic interventions for children with problem or self-injurious behaviors. Alterations in the gut microbiota of autistic children may result in metabolic and proteomic changes that trigger epigenetic, transcriptom-ic, and proteomic disturbances in the gastrointestinal tract of the child and result in deviations of neurodevelopment.
There are many examples in nature of how an enteric infection may modify behavior. Toxoplasma gondii, a parasite that infects rodents and causes loss of the innate fear of the smell of the urine of its natural predator, the bobcat, is an example of the impact of the microbiome on host behavior. When infected rodents become food for the bobcat, other rodents are infected by bob-cat feces, enabling the parasite to spread. Changes in personality have even been reported in people infected with Toxoplasma. Other examples of bacteria and viruses affecting human behavior are: rabies causing hydrophobia; streptococcal infection resulting in pediatric autoimmune neuropsychiatric disorders (PANDAS) and obsessive-compulsive disorders; and Brucella suis infection causing labile emotions. The impact of the microbiota on behavior in individuals with autism is not well understood, but for decades parents have observed that interventions, such as restricted diets, probiotics, or antibiotics, all of which may modify the intestinal microbiota may also change behavior.
Understanding the gastrointestinal microbiome and the impact on metabolic and other signaling pathways has provided new insights into behavior, mood, and eating patterns and is likely to have relevance to autism. For example, urine HPHPA, a metabolic product of phenylalanine is converted to m-Tyrosine by bacterial and human enzymes. In animal models, m-Tyrosine causes stereotypical behavior and hyperactivity. Autistic children may have increased fecal Clostridia and urinary m-Tyrosine and treatment with the antibiotic, metronidazole, decreases not only fecal Clostridia, but also urinary HPHPA. Furthermore, a short chain fatty acid metabolic end product of enteric bacteria, propoionic acid, has been demonstrated to elicit autism-like behavioral changes in rodents. These observations are currently largely theoretical, but these examples support the hypothesis that a mind-body-microbial connection may be relevant to understanding and treating autism. Generating new knowledge about how the metabolic products of microbiome impact on the relationship of the gastrointestinal tract with the mind and body of individuals with ASD could lead to a paradigm shift in our understanding of autism and how it is currently diagnosed and treated.
Dr. Winter is the Director of the Pediatric Inflammatory Bowel Disease Center at MassGeneral Hospital for Children and directs the pediatric GI Biorepository for the study of the intestinal microbiome. He specializes in pediatric gastroenterology and nutrition, and his clinical interests include immunodeficiency, inflammatory bowel disease, GI aspects of autism, and gastroesophageal reflux disease.
Robert L. Hendren, D.O.
Clinical Trials Updates and Discussion
Methyl B12 – Preliminary results from a second randomized controlled trial of injectable methyl B12 in children 3 to 7 years of age will be presented. Several measures show separation of active methyl B12 from placebo.
“Translating to Treatment” Multi-site study
We are planning a pilot study where we hope to enroll 50-100 children who are attending one of 5 “biomedical” clinics for evaluation and treatment of autism. The overarching goal is to try to see if we can find any signals – either in clinical response or changes in biomarkers – in children who are being prescribed biomedical treatments We expect that ultimately we will need a much larger sample to identify any important signals, but in this first stage, we are in the process of creating a network, data collection system, and laboratory evaluation protocol. These steps and more will be presented with encouragement for discussion from the group.
Robert L. Hendren, D.O., is Professor of Psychiatry and Behavioral Science; Director of Child and Adolescent Psychiatry and Vice Chair of the Department of Psychiatry at the University of California, San Francisco. He is the current (2007-2009) President of the American Academy of Child and Adolescent Psychiatry. His current areas of research and publication interests are translational clinical pharmacology and nutritional trials using biomarkers (MRI, measures of inflammation, oxidative stress, immune function and pharmacogenomics) in neurodevelopmental disorders. He has published over 100 scientific papers and four books.
Andrew W. Zimmerman, MD
Fever, Cellular Stress and Sulforaphane in Autism
Positive behavioral changes with fever have been described in autism but their causes are un-known. In view of the rapidity of onset of these changes, cellular stress responses may underlie functional changes in the CNS, including stimulation of heat shock proteins and upregulation of mitochondrial and peroxisomal pathways. Fever and its related biochemical and neurophysiolog-ical effects may therefore compensate for various underlying nonlethal defects of cellular func-tions. Sulforaphane (broccoli sprout extract) and other small molecular weight compounds acti-vate the cellular stress proteome and may compensate for these mild cellular phenotypes in sev-eral neurodevelopmental disorders, with both known and unknown genetic abnormalities. Our current double blind, placebo-controlled trial of sulforaphane in 45 young men, 13-30 years of age, is currently underway, and will provide both clinical and laboratory data on mitochondrial mass, heat shock proteins and antioxidant pathways.
Dr. Zimmerman is a pediatric neurologist and Director of Clinical Trials at the Lurie Center for Autism in Lexington, MA, and Associate Professor of Neurology at Harvard Medical School and the Johns Hopkins University School of Medicine.
James Adams, PhD
Discussion of an Autism Prevention Study Protocol
This session will involve a presentation of a draft protocol for an Autism Prevention Study, focused on nutritional support, decreasing toxic exposures, and individualized metabolic testing and treatment. The focus will be on an open-ended discussion of the draft protocol.
James B. Adams, PhD is a President’s Professor at Arizona State University, where he directs the Autism/Asperger’s Research Program. His work is focused on biomedical causes of autism and how to treat it, including nutritional status (vitamins, minerals, essential fatty acids, amino acids), metabolism, toxic metals/chelation, neurotransmitters, mitochondrial status, GI issues, and seizures.
Sidney Baker, MD
Gender Differences among Children with Autism Spectrum Disorders: Differential Symptom Patterns
I will present an analysis of gender differences in 79,482 symptoms and strengths in 1495 boys and 336 girls ages 2-18 from parent-identified autistic children an anonymous parent-entered online structurally novel database, Autism360. The differences revealed by the data provide previously undetected clues to gender-based differences in immune, central nervous system, and gastrointestinal functional disturbances. Combined with previously published observations of male female differences in inflammation, oxidative stress, and problems in detoxification these findings open paths to research focusing on gender-based physiologic mechanisms to reveal etiologic factors in autism. This study exemplifies a research method based on a large, detailed, patient-entered, structured data set in which patterns of individual heath descriptions may answer individual and collective questions about prevention and treatment.
Review of the literature of gender differences reveals relatively few and small differences from the neurodevelopmental perspective. In biochemistry, however, the research is limited within the autism field because girls’ data have often been excluded in the studies or gender has not been considered. Studies from Robert Clark’s group at U. of Pittsburg, however, reveals a striking contrast in mechanisms of cell death in XX versus XY neurons. These studies provide a topic for discussion relative to treatment options for boys versus girls in light of the recent findings of Richard Frye and Derrick MacFabe relative to mitochondrial dysfunction in autism.
Dr. Baker is a former Assistant Professor of Medical Computer Science of Yale Medical School, where he received his medical and specialty training in pediatrics. He is former director of the Gesell In-stitute of Human Development. In private practice in Sag Harbor, NY, he is the author of Detoxi-fication and Healing, Child Behavior (with Ilg and Ames), and We Band of Mothers: Autism, My Son & the Specific Carbohydrate Diet with Judith Chinitz; his practice focuses on treatment of adults and children with complex chronic illness. He is the Founder of Autism360.
[Addendum 4/28/13 photographs of the Think Tank event were added]