Boston Children's Hospital

About: Boston Children's Hospital is a healthcare organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Population & Transplantation. The organization has 165409 authors who have published 215589 publications receiving 6885627 citations.

An activated form of transforming growth factor beta is produced by cocultures of endothelial cells and pericytes.

Abstract: Using an in vitro coculture system to mimic the interactions between the cells of the vessel wall, we have previously shown that pericytes and smooth muscle cells (SMC) inhibit the growth of capillary endothelial cells (EC). We have undertaken studies to determine the mechanism of this inhibition. Using conditioned media and affinity-purified antibodies to transforming growth factor beta (TGF-beta), we now demonstrate that activated TGF-beta produced in these cocultures mediates EC growth inhibition. No inhibitory activity was detected when media conditioned by individual cultures of EC, SMC, or pericytes were examined for their effect on EC growth. In contrast, media conditioned by cocultures of EC-SMC and EC-pericytes inhibited EC proliferation to the same degree as the coculture itself. Immunoadsorption of coculture-derived conditioned media with antibodies to TGF-beta eliminated the inhibitory activity. Acid activation of serum-free media conditioned by any of the cells cultured alone yielded inhibitory activity, whereas activation of coculture conditioned media did not increase its inhibitory activity. Addition of anti-TGF-beta neutralizing antibodies to cocultures blocked the pericyte-mediated EC growth inhibition. These results indicate that latent TGF-beta is produced by these cells and it is activated by a mechanism that requires contact between the two cell types.

Composition of the adult digestive tract bacterial microbiome based on seven mouth surfaces, tonsils, throat and stool samples

Abstract: Background: To understand the relationship between our bacterial microbiome and health, it is essential to define the microbiome in the absence of disease. The digestive tract includes diverse habitats and hosts the human body’s greatest bacterial density. We describe the bacterial community composition of ten digestive tract sites from more than 200 normal adults enrolled in the Human Microbiome Project, and metagenomically determined metabolic potentials of four representative sites. Results: The microbiota of these diverse habitats formed four groups based on similar community compositions: buccal mucosa, keratinized gingiva, hard palate; saliva, tongue, tonsils, throat; sub- and supra-gingival plaques; and stool. Phyla initially identified from environmental samples were detected throughout this population, primarily TM7, SR1, and Synergistetes. Genera with pathogenic members were well-represented among this disease-free cohort. Tooth-associated communities were distinct, but not entirely dissimilar, from other oral surfaces. The Porphyromonadaceae, Veillonellaceae and Lachnospiraceae families were common to all sites, but the distributions of their genera varied significantly. Most metabolic processes were distributed widely throughout the digestive tract microbiota, with variations in metagenomic abundance between body habitats. These included shifts in sugar transporter types between the supragingival plaque, other oral surfaces, and stool; hydrogen and hydrogen sulfide production were also differentially distributed. Conclusions: The microbiomes of ten digestive tract sites separated into four types based on composition. A core set of metabolic pathways was present across these diverse digestive tract habitats. These data provide a critical baseline for future studies investigating local and systemic diseases affecting human health.

Medical assessment of adverse health outcomes in long-term survivors of childhood cancer

Abstract: ContextImproved survival of children with cancer has been accompanied by multiple treatment-related complications. However, most studies in survivors of childhood cancer focused on only 1 late effect.ObjectiveTo assess the total burden of adverse health outcomes (clinical or subclinical disorders [“adverse events”]) following childhood cancer in a large cohort of childhood cancer survivors with long-term and complete medical follow-up.Design, Setting, and PopulationRetrospective cohort study of 1362 five-year survivors of childhood cancer treated in a single institution in the Netherlands between 1966 and 1996. All survivors were invited to a late-effects clinic for medical assessment of adverse events. Adverse events occurring before January 2004 were graded for severity in a standardized manner.Main Outcome MeasuresTreatment-specific prevalence of adverse events (according to severity) at end of follow-up and relative risk of high or severe burden of disease (≥2 severe or ≥1 life-threatening or disabling adverse events) associated with various treatments.ResultsMedical follow-up was complete for 94.3% of survivors (median follow-up, 17.0 years). The median attained age at end of follow-up was 24.4 years. Almost 75% of survivors had 1 or more adverse events, and 24.6% had 5 or more adverse events. Furthermore, 40% of survivors had at least 1 severe or life-threatening or disabling adverse event. A high or severe burden of adverse events was observed in 55% of survivors who received radiotherapy only and 15% of survivors treated with chemotherapy only, compared with 25% of survivors who had surgery only (adjusted relative risks, 2.18 [95% confidence interval, 1.62–2.95] and 0.65 [95% confidence interval, 0.46–0.90], respectively). A high or severe burden of adverse events was most often observed in survivors of bone tumors (64%) and least often in survivors of leukemia or Wilms tumor (12% each).ConclusionsIn young adulthood, a substantial proportion of childhood cancer survivors already has a high or severe burden of disease, particularly after radiotherapy. This underscores the need for lifelong risk-stratified medical surveillance of childhood cancer survivors.