Monitoring TRPC7 Conformational Changes by BRET Following GPCR Activation

Transient receptor potential canonical (TRPC) channels are membrane proteins involved in regulating Ca²⁺ homeostasis, and whose functions are modulated by G protein-coupled receptors (GPCR). In this study, we developed bioluminescent resonance energy transfer (BRET) biosensors to better study channel conformational changes following receptor activation. For this study, two intramolecular biosensors, GFP10-TRPC7-RLucII and RLucII-TRPC7-GFP10, were constructed and were assessed following the activation of various GPCRs. We first transiently expressed receptors and the biosensors in HEK293 cells, and BRET levels were measured following agonist stimulation of GPCRs. The activation of GPCRs that engage Gα_q led to a Gα_q-dependent BRET response of the functional TRPC7 biosensor. Focusing on the Angiotensin II type-1 receptor (AT₁R), GFP10-TRPC7-RLucII was tested in rat neonatal cardiac fibroblasts, expressing endogenous AT₁R and TRPC7. We detected similar BRET responses in these cells, thus validating the use of the biosensor in physiological conditions. Taken together, our results suggest that activation of Gα_q-coupled receptors induce conformational changes in a novel and functional TRPC7 BRET biosensor.

Dust observations at orbital altitudes surrounding Mars

Dust is common close to the martian surface, but no known process can lift appreciable concentrations of particles to altitudes above ~150 kilometers. We present observations of dust at altitudes ranging from 150 to above 1000 kilometers by the Langmuir Probe and Wave instrument on the Mars Atmosphere and Volatile Evolution spacecraft. Based on its distribution, we interpret this dust to be interplanetary in origin. A comparison with laboratory measurements indicates that the dust grain size ranges from 1 to 12 micrometers, assuming a typical grain velocity of ~18 kilometers per second. These direct observations of dust entering the martian atmosphere improve our understanding of the sources, sinks, and transport of interplanetary dust throughout the inner solar system and the associated impacts on Mars's atmosphere.

Structure of an exploding laser-produced plasma

We describe the first-ever volumetric, time-resolved measurements performed with a moving probe within an expanding dense plasma, embedded in a background magnetized plasma. High-resolution probe measurements of the magnetic field and floating potential in multiple 2D cut planes combined with a 1 Hz laser system reveal complex three-dimensional current systems within the expanding plasma. Static (ωreal=0) flutelike density striations are observed at the leading edge of the plasma, which are correlated to variations in the current layer at the edge of the expanding plasma.

Two-dimensional micron-step probe drive for laboratory plasma measurement

Laboratory measurement of small-scale ( approximately 1 mm) magnetic phenomena over an extended area is a challenge requiring precise diagnostics. We present a novel two dimensional magnetic probe platform capable of directly measuring the magnetic field over a 36 cm(2) region at spatial resolutions better than 1 mm. The platform is discussed in the context of an experiment at the Large Plasma Device facility at UCLA, designed to measure the magnetic interaction between two counterpropagating laser-produced plasmas. The use of a precise, repeatable positioning platform enables the recovery of information about the interaction using cross-correlation techniques.

ISEApeaks: an Excel platform for GeneScan and Immunoscope data retrieval, management and analysis

ISEApeaks retrieves and handles DNA sequencer raw data (peak area and nucleotidic length). This Macintosh package efficiently interfaces GeneScan and Immunoscope softwares to Excel by extracting data from scattered files, organizing data and gathering it into a unique peak database for all samples.

Collaborative partnership for optimizing heart failure outcomes in the long-term care environment: a clinical experience

RATIONALE

Heart failure (HF) is a devastating cardiovascular syndrome affecting more than 4.6 million Americans and resulting in a substantial economic burden. It is the number one cause of hospitalization in the older population. Because there is no cure for this costly disease, goals of therapy include; slowing progression, increasing patient survival, minimizing symptoms, improving patient functional capacity, and decreasing ER visits, hospital admissions, and readmissions. Studies have shown ACE inhibitors (ACEIs) to be extremely beneficial in reaching these goals. However, data nationwide indicate that less than half of HF patients are prescribed an ACEI. Therefore, a national long-term care pharmaceutical provider has committed to the development of a HF disease management program, which has been implemented through a collaborative partnership between medicine, nursing, and pharmacy. This report describes the experience and results of implementing this program in a large group of nursing homes.

METHODS

With help from an independent health outcomes consulting firm and an expert panel, a multifaceted program was developed. The AMDA heart failure guidelines were used as a foundation to design program interventions, which included educational programs for the long-term care facility staff, implementation of a HF treatment algorithm, and an outcomes measurement program. The primary goals of this program were to increase awareness of HF and treatment options available and to decrease morbidity and mortality associated with HF through the optimization of pharmacologic management in a long-term care setting.

OUTCOMES

A retrospective evaluation was conducted to assess changes in ACEI utilization, ACEI targeted dosing and HF-related hospitalizations 1 year after program implementation. A total of 510 patients followed by 23 consultants, representing 152 facilities met the inclusion criteria for the analysis. Data indicated an increase of 36% in newly enrolled HF patients utilizing ACEI after 1 year. A decreasing trend in HF hospitalizations was also noted from the first quarter, (2.2/100 patients) to the fourth (1.0/100 patients). The results of the Heart Failure-Health Outcomes Management Program (HF-HOMP) program demonstrate the opportunity existing for long-term care providers to improve patient health while minimizing expenditures. It also provides additional evidence that such programs should be implemented more broadly within this population.

T cell response in malaria pathogenesis: selective increase in T cells carrying the TCR V(beta)8 during experimental cerebral malaria

To characterize the T cells involved in the pathogenesis of cerebral malaria (CM) induced by infection with Plasmodium berghei ANKA clone 1.49L (PbA 1.49L), the occurrence of the disease was assessed in mice lacking T cells of either the alphabeta or gammadelta lineage (TCRalphabeta(-/-) or TCRgammadelta(-/-)). TCRgammadelta(-/-) mice were susceptible to CM, whereas all TCRalphabeta(-/-) mice were resistant, suggesting that T cells of the alphabeta lineage are important in the genesis of CM. The repertoire of TCR V(beta) segment gene expression was examined by flow cytometry in B10.D2 mice, a strain highly susceptible to CM induced by infection with PbA 1.49L. In these mice, CM was associated with an increase of T cells bearing the V(beta)8.1, 2 segments in the peripheral blood lymphocytes. Most V(beta)8.1, 2(+) T cells from peripheral blood lymphocytes of the mice that developed CM belonged to the CD8 subset, and exhibited the CD69(+), CD44(high) and CD62L(low) phenotype surface markers. The link between the increase in V(beta)8.1, 2(+) T cells and the neuropathological consequences of PbA infection was strengthened by the observation that the occurrence of CM was significantly reduced in mice treated with KJ16 antibodies against the V(beta)8.1 and V(beta)8.2 chains, and in mice rendered deficient in V(beta)8.1(+) T cells by a mouse mammary tumor virus superantigen.