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The goal of Diabetes Today, a program of the Centers for Disease Control and Prevention (CDC), is to develop coalitions and train coalition members in assessment, planning, and evaluation to address diabetes in their communities. CDC established the Pacific Diabetes Today Resource Center (PDTRC) in 1998 to tailor the program for Pacific Islander communities in Hawaii, American Samoa, Guam, the Commonwealth of the Northern Marianas Islands, the Federated States of Micronesia, the Republic of the Marshall Islands, and Palau. PDTRC's work is guided by the principles of community building and the goal of empowering coalitions to take action around diabetes. Culturally appropriate strategies are used to gain access to the community, transfer knowledge and skills, build coalitions, and provide technical assistance. Evidence of empowerment is seen in increased individual competence, enhanced community capacity, reduced barriers, and improved supports to address diabetes. To maintain the gains of community building in the Pacific, three factors appear critical: an engaged leader, a host agency for the coalition, and continuing access to technical assistance and funds. [ABSTRACT FROM AUTHOR]

All natural organisms store genetic information in a four-letter, two-base-pair genetic alphabet. The expansion of the genetic alphabet with two synthetic unnatural nucleotides that selectively pair to form an unnatural base pair (UBP) would increase the information storage potential of DNA, and semisynthetic organisms (SSOs) that stably harbor this expanded alphabet would thereby have the potential to store and retrieve increased information. Toward this goal, we previously reported that Escherichia coli grown in the presence of the unnatural nucleoside triphosphates dNaMTP and d5SICSTP, and provided with the means to import them via expression of a plasmid-borne nucleoside triphosphate transporter, replicates DNA containing a single dNaM-d5SICS UBP. Although this represented an important proof-of-concept, the nascent SSO grew poorly and, more problematically, required growth under controlled conditions and even then was unable to indefinitely store the unnatural information, which is clearly a prerequisite for true semisynthetic life. Here, to fortify and vivify the nascent SSO, we engineered the transporter, used a more chemically optimized UBP, and harnessed the power of the bacterial immune response by using Cas9 to eliminate DNA that had lost the UBP. The optimized SSO grows robustly, constitutively imports the unnatural triphosphates, and is able to indefinitely retain multiple UBPs in virtually any sequence context. This SSO is thus a form of life that can stably store genetic information using a six-letter, three-base-pair alphabet., Competing Interests: Y.Z., B.M.L., and F.E.R. have filed a patent application based on the use of Cas9 for enforced retention of the UBP. Y.Z. and F.E.R. have filed a patent application for the truncated transporter. F.E.R. has a financial interest (shares) in Synthorx Inc., a company that has commercial interests in the UBP. The other authors declare no other competing financial interests.

A routine thioketal protecting group reacts rapidly and selectively with singlet oxygen to reveal ketone products in good (aryl 1,3-dithiolane) to excellent (aryl 1,3-oxathiolane) yields. Arylthiolanes are stable to biologically relevant reactive oxygen species and can be used as a light-activated gating mechanism for activating fluorescent sensors or small molecule prodrugs.

The construction of increasingly sophisticated synthetic biological circuits is dependent on the development of extensible tools capable of providing specific control of gene expression in eukaryotic cells. Here, we describe a new class of synthetic transcription factors that activate gene expression in response to extracellular chemical stimuli. These inducible activators consist of customizable transcription activator-like effector (TALE) proteins combined with steroid hormone receptor ligand-binding domains. We demonstrate that these ligand-responsive TALE transcription factors allow for tunable and conditional control of gene activation and can be used to regulate the expression of endogenous genes in human cells. Since TALEs can be designed to recognize any contiguous DNA sequence, the conditional gene regulatory system described herein will enable the design of advanced synthetic gene networks.

We report a general cell surface molecular engineering strategy via liposome fusion delivery to create a dual photo-active and bio-orthogonal cell surface for remote controlled spatial and temporal manipulation of microtissue assembly and disassembly. Cell surface tailoring of chemoselective functional groups was achieved by a liposome fusion delivery method and quantified by flow cytometry and characterized by a new cell surface lipid pull down mass spectrometry strategy. Dynamic co-culture spheroid tissue assembly in solution and co-culture tissue multilayer assembly on materials was demonstrated by an intercellular photo-oxime ligation that could be remotely cleaved and disassembled on demand. Spatial and temporal control of microtissue structures containing multiple cell types was demonstrated by the generation of patterned multilayers for controlling stem cell differentiation. Remote control of cell interactions via cell surface engineering that allows for real-time manipulation of tissue dynamics may provide tools with the scope to answer fundamental questions of cell communication and initiate new biotechnologies ranging from imaging probes to drug delivery vehicles to regenerative medicine, inexpensive bioreactor technology and tissue engineering therapies.

An assay was developed for determining cell division orientation on gradients. The methodology is based on permeating microfluidic devices with alkanethiols and subsequent printing of cell adhesive peptide gradient self-assembled monolayers (SAMs) for examining oriented cell divisions. To our knowledge, there has been no study examining the correlation between cell division orientations based on an underlying ligand gradient. These results implicate an important role for how the extracellular matrix may control cell division. These surfaces would allow for a range of cell behavior (polarization, migration, division, differentiation) studies on tailored biospecific gradients and as a potential biotechnological platform to assess small molecule perturbations of cell function.

Transcription activator-like effector (TALE) proteins can be designed to bind virtually any DNA sequence. General guidelines for design of TALE DNA-binding domains suggest that the 5'-most base of the DNA sequence bound by the TALE (the N0 base) should be a thymine. We quantified the N0 requirement by analysis of the activities of TALE transcription factors (TALE-TF), TALE recombinases (TALE-R) and TALE nucleases (TALENs) with each DNA base at this position. In the absence of a 5' T, we observed decreases in TALE activity up to >1000-fold in TALE-TF activity, up to 100-fold in TALE-R activity and up to 10-fold reduction in TALEN activity compared with target sequences containing a 5' T. To develop TALE architectures that recognize all possible N0 bases, we used structure-guided library design coupled with TALE-R activity selections to evolve novel TALE N-terminal domains to accommodate any N0 base. A G-selective domain and broadly reactive domains were isolated and characterized. The engineered TALE domains selected in the TALE-R format demonstrated modularity and were active in TALE-TF and TALEN architectures. Evolved N-terminal domains provide effective and unconstrained TALE-based targeting of any DNA sequence as TALE binding proteins and designer enzymes.

A general surface chemistry strategy is described for the development of a new switchable material. The method modulates a surface-immobilized-molecules structure by using two orthogonal "click" reactions based on Huisgen cycloaddition and oxime chemistry, where the oxime linkage is redox active and switchable. We demonstrate this strategy by developing a noninvasive, biocompatible, in situ surface chemistry that is able to modulate the affinity of a cell-adhesive peptide to cell integrin receptors to study dynamic cell adhesion and cell migration in real time and as a new hide-and-reveal strategy for application in new types of smart biofouling biomaterials., (© 2011 American Chemical Society)

To study complex cell behavior on model surfaces requires biospecific interactions between the interfacing cell and material. Developing strategies to pattern well-defined molecular gradients on surfaces is difficult but critical for studying cell adhesion, polarization, and directed cell migration. We introduce a new strategy, microfluidic SPREAD (Solute PeRmeation Enhancement And Diffusion) for inking poly(dimethylsiloxane) (PDMS) microfluidic cassettes with a gradient of alkanethiol. Using SPREAD, an oxyamine-terminated alkanethiol is able to permeate into a PDMS microfluidic cassette, creating a chemical gradient, which can subsequently be transfer printed onto a gold surface to form the corresponding chemoselective gradient of oxyamine-alkanethiol self-assembled monolayer (SAM). By first patterning regions of the gold surface with a protective SAM using microfluidic lithography, directional gradients can be stamped exclusively onto unprotected bare gold regions to form single cell gradient microarrays. The microfluidic SPREAD strategy can also be extended to print micrometer-sized islands of radial SAM gradients with excellent geometric resolution. The immobilization of a cell adhesive Arg-Gly-Asp (RGD)-ketone peptide to the SPREAD stamped oxyamine-alkanethiol SAMs provides a stable interfacial oxime linkage for biospecific studies of cell adhesion, polarity, and migration.

To generate patterned substrates of self-assembled monolayers (SAMs) for cell adhesion and migration studies, a variety of gold/glass hybrid substrates were fabricated from gold evaporated on glass. A variety of surfaces were generated including gradients of gold height, completely etched gold/glass hybrids, and partially etched gold surfaces for pattern visualization. Etch rates were controlled by the alkanethiol present on the surface. Gradients of gold height were created using an electrochemical etch with control over the position and slope of the gold height gradient. Cells were seeded to these surfaces, and their adhesion to the gold was controlled by the surface chemistry present in the channel regions. In the future, the etched gold surfaces will be used to simulate the varying nanotopology experienced by the migrating cell in vivo.

A straightforward, flexible, and inexpensive method to etch biodegradable poly(1,2,6-hexanetriol alpha-ketoglutarate) films is reported. Microfluidic delivery of the etchant, a solution of NaOH, can create micron-scale channels through local hydrolysis of the polyester film. In addition, the presence of a ketone in the repeat unit allows for prior or post chemoselective modifications, enabling the design of functionalized microchannels. Delivery of oxyamine tethered ligands react with ketone groups on the polyketoester to generate covalent oxime linkages. By thermally sealing an etched film to a second flat surface, poly(1,2,6-hexanetriol alpha-ketoglutarate) can be used to create biodegradable microfluidic devices. In order to determine the versatility of the microfluidic etch technique, poly(epsilon-caprolactone) was etched with acetone. This strategy provides a facile method for the direct patterning of biodegradable materials, both through etching and chemoselective ligand immobilization.

An expedient and inexpensive method to generate patterned aldehydes on self-assembled monolayers (SAMs) of alkanethiolates on gold with control of density for subsequent chemoselective immobilization from commercially available starting materials has been developed. Utilizing microfluidic cassettes, primary alcohol oxidation of tetra(ethylene glycol) undecane thiol and 11-mercapto-1-undecanol SAMs was performed directly on the surface generating patterned aldehyde groups with pyridinium chlorochromate. The precise density of surface aldehydes generated can be controlled and characterized by electrochemistry. For biological applications, fibroblast cells were seeded on patterned surfaces presenting biospecifc cell adhesive (Arg-Glyc-Asp) RGD peptides.

A straightforward, flexible, and inexpensive method to create patterned self-assembled monolayers (SAMs) on gold using microfluidics-microfluidic lithography-has been developed. Using a microfluidic cassette, alkanethiols were rapidly patterned on gold surfaces to generate monolayers and mixed monolayers. The patterning methodology is flexible and, by controlling the solvent conditions and thiol concentration, permeation of alkanethiols into the surrounding PDMS microfluidic cassette can be advantageously used to create different patterned feature sizes and to generate well-defined SAM surface gradients with a single microfluidic chip. To demonstrate the utility of microfluidic lithography, multiple cell experiments were conducted. By patterning cell adhesive regions in an inert background, a combination of selective masking of the surface and centrifugation achieved spatial and temporal control of patterned cells, enabling the design of both dynamic surfaces for directed cell migration and contiguous cocultures. Cellular division and motility resulted in directed, dynamic migration, while the centrifugation-aided seeding of a second cell line produced contiguous cocultures with multiple sites for heterogeneous cell-cell interactions.

A continuous quality care improvement program (CQIP) was built into Project DIRECT (Diabetes Interventions Reaching and Educating Communities Together) to improve providers' patterns of diabetes care and patients' glycemic control. Project DIRECT consisted of a comprehensive program aimed at reducing the burden of diabetes in the vulnerable high-risk African-American population of southeast Raleigh, NC. Forty-seven providers caring for this target population of adult diabetes patients were included in this quasi-experimental study. At the initial session, providers learned about the CQIP components, completed a planning worksheet, and chose a CQIP coordinator. Educational events included continuing education in practices and through conferences by experts, and guideline distribution. Follow-up was accomplished through phone calls and visits. Effectiveness was measured by a change in prevalence of selected patterns of care abstracted from 1,006 medical charts. Appropriate statistical methods were used to account for the cluster design and repeated measures. At the fourth follow-up year, approximately 40% of providers still participated in the program. Among the providers who stayed in the program for the whole study period, most selected quality care patterns showed significant upward trends. Glycemic control indicators did not change, however, despite an increased number of hemoglobin A1c tests per year. A diabetes CQI program can be effectively implemented in a community setting. Improved performance measures were not associated with improved outcomes. These results suggest that a patient-centered component should reinforce the provider-centered component.

Study Objective: Nebulizer systems used to generate therapeutic aerosols vary in their ability to deliver medication to the airway. In a recent study in 17 adults with stable asthma, albuterol given using an ultrasonic nebulizer (UN) appeared to produce greater bronchodilatation than the same dose of albuterol given by a jet nebulizer (JN). The purpose of this study was to determine if the UN used in that study would produce a better bronchodilator response in children with acute asthma than the JN system that has been in use at Cardinal Glennon Children's Hospital., Design: Randomized, prospective, unblinded study., Setting: An urban university children's hospital emergency department., Participants: One hundred thirteen children, aged 7 to 16 years, who presented for treatment of acute moderately severe asthma completed this study., Interventions: After randomization and exclusion of dropouts, 46 children received albuterol by UN and 67 were treated by JN., Measurements: Pulmonary function tests (PFTs) by spirometry, pulse oximetry, and symptom score at baseline and at 15 and 30 min following a single prescribed treatment., Results: PFT on entry to the study was the same in both groups (FEV1; p>0.97). The change in FEV1 after therapy (UN+0.22 L vs JN+0.37 L) was significant (p<0.05) and favored JN. There was no difference in the improvement in pulmonary function between JN and UN therapy in children with an initial FEV1/FVC > 75% predicted but when FEV1/FVC < 75%, the improvement in FEV1 again favored the JN (UN+0.2 vs JN+0.47; p<0.05)., Conclusion: For the treatment of acute exacerbations of asthma in children, there is no greater bronchodilator response when albuterol is administered by a UN than by a JN.