Energy Gradients Structure Microbial Communities Across Sediment Horizons in Deep Marine Sediments of the South China Sea

The deep marine subsurface is a heterogeneous environment in which the assembly of microbial communities is thought to be controlled by a combination of organic matter deposition, electron acceptor availability, and sedimentology. However, the relative importance of these factors in structuring microbial communities in marine sediments remains unclear. The South China Sea (SCS) experiences significant variability in sedimentation across the basin and features discrete changes in sedimentology as a result of episodic deposition of turbidites and volcanic ashes within lithogenic clays and siliceous or calcareous ooze deposits throughout the basin\u27s history. Deep subsurface microbial communities were recently sampled by the International Ocean Discovery Program (IODP) at three locations in the SCS with sedimentation rates of 5, 12, and 20 cm per thousand years. Here, we used Illumina sequencing of the 16S ribosomal RNA gene to characterize deep subsurface microbial communities from distinct sediment types at these sites. Communities across all sites were dominated by several poorly characterized taxa implicated in organic matter degradation, including Atribacteria, Dehalococcoidia, and Aerophobetes. Sulfate-reducing bacteria comprised only 4% of the community across sulfate-bearing sediments from multiple cores and did not change in abundance in sediments from the methanogenic zone at the site with the lowest sedimentation rate. Microbial communities were significantly structured by sediment age and the availability of sulfate as an electron acceptor in pore waters. However, microbial communities demonstrated no partitioning based on the sediment type they inhabited. These results indicate that microbial communities in the SCS are structured by the availability of electron donors and acceptors rather than sedimentological characteristics

Development, Implementation, and Assessment of Health Equity Action Training (HEAT): Implications for Local Health Departments

As inequities in health persistently plague our nation, rates of chronic disease continue to escalate, and increasing health care costs further debilitate our economy, the profession of public health is faced with monumental challenges. As a central community health institution, the local public health department plays an essential role in eliminating health inequities and preventing chronic disease. With the objective of preparing the local public health workforce to address the root factors associated with health, the Health Equity Action Training project trained 85 staff of the Hartford Department of Health & Human Services in the social determinants of health, social inequities, undoing racism, and cultural competency. Satisfaction results and pre/post assessments with a subsample of participants suggest that this training was effective at improving participants’ health equity attitudes, knowledge, and skills. Implications for local health departments are discussed

Development of a three dimensional cell culture model for primary human articular chondrocytes to test the efficacy of osteoarthritis treatments

The objective of this study was to establish a culture system of primary human articular chondrocytes with which to test novel drugs for the treatment of osteoarthritis (OA). Articular cartilage was obtained from OA subjects undergoing total knee arthroplasty (TKA) or above knee amputation (AKA). Chondrocytes were isolated by protease digestion and cultured in alginate at 2.5, 5, 10 x 106 cells in serum, hormone, and growth factor free medium. Production of collagen degradation products was measured in days 2 and 5 culture medium and day 5 cell associated matrix. The optimal plating density was 2.5 x 106 cells/mL, as determined by end point analysis. Cell yield and collagen breakdown products were higher in cultures established from the tibial plateau and femoral condyle than from the patella. Proteoglycans, collagen, and collagen breakdown products were detected in all OA cultures. However, the production of collagen breakdown products differed significantly between the side of greatest pathology and contralateral region within each subject. These results demonstrate that human articular chondrocytes survive and are metabolically active when cultured in this serum-free, 3D culture system. The femoral condyles and tibial plateau were the optimal sites for tissue harvesting. With this model system we can effectively measure clinical endpoints for testing new drugs that may reduce tissue destruction in OA

Measuring Clinically Relevant Endpoints in a Serum-Free, Three-Dimensional, Primary Cell Culture System of Human Osteoarthritic Articular Chondrocytes

Osteoarthritis (OA) is characterized by degeneration of articular cartilage within the joint, inflammation and pain. The purpose of this study was to develop a primary, serum free cell culture system of human osteoarthritic articular chondrocytes (HOACs) with which to study manifestations of the disease process. Joint tissues were obtained from OA patients undergoing total knee arthroplasty (TKA). HOACs isolated from the femoral condyles and tibial plateau of the same side were combined, plated in three-dimensional, alginate beads and cultured for five days in serum, hormone and protein free medium. More living cells were obtained from the femoral condyles than the tibial plateau. The optimal plating density was 2.5 × 10(6) cells/ml of alginate. The amounts of DNA, RNA, proteoglycans and total collagen were similar in cultures prepared from the sides of least and greatest pathology. More type 1 than type 2 collagen was detected in the medium on days 2 and 5. A greater percentage of type 1 than type 2 collagen was degraded. The inflammatory cytokine interleukin-1 beta was present in the medium and alginate associated matrix. Although variation in the metabolic profiles between subjects was observed, HOACs from all patients continued to reflect the OA phenotype for five days in culture. This serum free, three-dimensional primary culture system of HOACs provides a platform with which to measure clinically relevant endpoints of OA and screen potential disease modifying OA therapeutics