Assessment of brain function in clinical pediatric research: behavioral and biological strategies.

Psychobiological research in child psychiatry requires rigorous assessment of behavior and multiple perspectives on brain function through neurochemical, neuroendocrine, psychophysiological, and other advanced methods. The serious neuropsychiatric disorders of childhood, such as autism, attention deficit disorder, and language disorders, can be studied in complementary clinical protocols aimed at explicating patterns of behavioral and metabolic dysfunction which characterize various clinical syndromes. Clinical research with children raises sensitive ethical issues; the ethical problems can be addressed when children and families are active collaborators with the investigators and a long-term relationship is established. In this setting, participation in research can facilitate better treatment for a child. The use of novel biological strategies, such as pharmacological challenge tests, permits evaluation of the relation of specific neuronal systems to behavioral dimensions in clinical disorders. The development of a new treatment for Tourette's syndrome illustrates the integration of basic and clinical research methods.

Clinical neurochemistry of autism and associated disorders.

Advances in information concerning brain function in animals and advances in analytical neurochemical methods for determining extremely low levels of compounds in physiological fluids have opened great opportunities for clinical neurochemical studies of autism. Nevertheless, the behavioral deficits in autistic individuals are major obstacles to clarification of the relations between symptoms and biochemical dysfunction in the brain. The fundamental preclinical and clinical studies of serotonin, dopamine, and norepinephrine metabolism related to infantile autism are reviewed, and new studies are suggested as examples of the productive strategies that will illuminate features of the autistic syndrome in the next decade.

The esophagitis to adenocarcinoma sequence; the role of inflammation.

Esophageal adenocarcinoma (EAC) is the eighth most common cancer worldwide, and approximately 15% of patients survive 5years. Reflux disease (GERD) and Barrett's esophagus (BE) are major risk factors for the development of EAC, and epidemiologic studies highlight a strong association with obesity. The immune, inflammatory and intracellular signaling changes resulting from chronic inflammation of the esophageal squamous epithelium are increasingly well characterized. In GERD and Barrett's, an essential role for T-cells in the initiation of inflammation in the esophagus has been identified, and a balance between T-cell responses and phenotype may play an important role in disease progression. Obesity is a chronic low-grade inflammatory state, fueled by adipose tissue derived- inflammatory mediators such as IL-6, TNF-α and leptin, representing a novel area for targeted research. Additionally, reactive oxygen species (ROS) and receptor tyrosine kinase (RTK) activation may drive progression from esophagitis to EAC, and downstream signaling pathways employed by these molecules may be important. This review will explain the diverse range of mechanisms potentially driving and maintaining inflammation within the esophagus and explore both existing and future therapeutic strategies targeting the process.