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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

COnTORT: COmprehensive Transcriptomic ORganizational Tool for Simultaneously Retrieving and Organizing Numerous Gene Expression Data Sets from the NCBI Gene Expression Omnibus Database

We introduce COnTORT ( CO mprehensive T ranscriptomic OR ganizational T ool), a publicly available program that retrieves all available gene expression data and associated metadata for an organism from the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) database. The data are compiled into text files that can be used for downstream bioinformatic applications.

Myers, Kevin S.↗
DOE OSTI2016

Heterologous expression and purification of catalytic domain of CESA1 from Arabidopsis thaliana

Here, heterologous expression of plant cellulose synthase (CESA) and its purification has remained a challenge for decades impeding detailed biophysical, biochemical and structural characterization of this key enzyme. An in-depth knowledge of structure and function of CESA proteins would enable us to better understand the hierarchical structure of the plant cell wall. Here, we report a detailed, and reproducible method of purification of catalytic domain of CESA1 from Arabidopsis thaliana that was recombinantly expressed in Escherichia coli . The method relies on a two stage purification procedure to obtain the catalytic domain in monomer and trimer forms. The biochemical and biophysical data including low resolution structures of the protein have been published. Currently the crystallization studies of this protein are underway.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS2008

The Challenges and Opportunities for International Cooperative Radio Science; Experience with Mars Express and Venus Express Missions

Radio Science is an opportunistic discipline in the sense that the communication link between a spacecraft and its supporting ground station can be used to probe the intervening media remotely. Radio science has recently expanded to greater, cooperative use of international assets. Mars Express and Venus Express are two such cooperative missions managed by the European Space Agency with broad international science participation supported by NASA's Deep Space Network (DSN) and ESA's tracking network for deep space missions (ESTRAK). This paper provides an overview of the constraints, opportunities, and lessons learned from international cross support of radio science, and it explores techniques for potentially optimizing the resultant data sets.

MEX↗
DOE OSTI2015

Visualization of the human CD4{sup +} T-cell response in humanized HLA-DR4-expressing NOD/Shi-scid/γc{sup null} (NOG) mice by retrogenic expression of the human TCR gene

Highlights: • β-Lactoglobulin (BLG) specific TCR genes were introduced to human HSC by retrovirus. • Human HSC with BLG-specific TCR were transplanted into NOG-HLA-DR4 I-A{sup −/−} mice. • BLG-specific TCR induced positive selection of thymocytes. • BLG-specific TCR positive CD4{sup +} T cells mediated immune responses in humanized mice. - Abstract: The development of severe immunodeficient mouse strains containing various human genes, including cytokines or HLA, has enabled the reconstitution of functional human immune systems after transplantation of human hematopoietic stem cells (HSC). Accumulating evidence has suggested that HLA-restricted antigen-specific human T-cell responses can be generated in these humanized mice. To directly monitor immune responses of human CD4{sup +} T cells, we introduced β-lactoglobulin (BLG)-specific T cell receptor (TCR) genes derived from CD4{sup +} T-cell clones of cow-milk allergy patients into HSCs, and subsequently transplanted them into NOG-HLA-DR4 transgenic/I-Aβ deficient mice (NOG-DR4/I-A{sup o}). In the thymus, thymocytes with BLG-specific TCR preferentially differentiated into CD4{sup +}CD8{sup −} single-positive cells. Adoptive transfer of mature CD4{sup +} T cells expressing the TCR into recipient NOG-DR4/I-A{sup o} mice demonstrated that human CD4{sup +} T cells proliferated in response to antigenic stimulation and produced IFN-γ in vivo, suggesting that functional T-cell reactions (especially Th1-skewed responses) were induced in humanized mice.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2014

ERK Oscillation-Dependent Gene Expression Patterns and Deregulation by Stress-Response

Studies were undertaken to determine whether ERK oscillations regulate a unique subset of genes in human keratinocytes and subsequently, whether the p38 stress response inhibits ERK oscillations. A DNA microarray identified many genes that were unique to ERK oscillations, and network reconstruction predicted an important role for the mediator complex subunit 1 (MED1) node in mediating ERK oscillation-dependent gene expression. Increased ERK-dependent phosphorylation of MED1 was observed in oscillating cells compared to non-oscillating counterparts as validation. Treatment of keratinocytes with a p38 inhibitor (SB203580) increased ERK oscillation amplitudes and MED1 and phospho-MED1 protein levels. Bromate is a probable human carcinogen that activates p38. Bromate inhibited ERK oscillations in human keratinocytes and JB6 cells and induced an increase in phospho-p38 and decrease in phospho-MED1 protein levels. Treatment of normal rat kidney cells and primary salivary gland epithelial cells with bromate decreased phospho-MED1 levels in a reversible fashion upon treatment with p38 inhibitors (SB202190; SB203580). Our results indicate that oscillatory behavior in the ERK pathway alters homeostatic gene regulation patterns and that the cellular response to perturbation may manifest differently in oscillating vs non-oscillating cells.

carcinogenesis↗
DOE OSTI2018

Co-expression of CD39 and CD103 identifies tumor-reactive CD8 T cells in human solid tumors

Identifying tumor antigen-specific T cells from cancer patients has been a goal of tumor immunologists for several decades. Here we show that co-expression of CD103 and CD39 on CD8 TIL highly enriched for tumor-reactive T cells. This cell population, which is only present in TIL from primary and metastatic tumors, exhibited features of exhausted cells and displayed characteristics of tissue-resident memory T cells. CD39+CD103+ CD8 TIL had a distinct TCR repertoire compared to other CD8 TIL subsets and were clonally expanded within the tumor. They were highly enriched for tumor antigen recognition and efficiently killed autologous tumor cells. Finally, patients with head and neck cancer whose CD8 TIL contained a higher frequency of CD39+CD103+ cells experienced a greater overall survival. This work describes a simple method for detecting tumor-reactive CD8 TIL, which should help define mechanisms of current immunotherapies and may lead to the development of future immunotherapies.

cancer, immunotherapy, transcriptomics, t-cells, h↗
NASA NTRS2002

Expression of a calpastatin transgene slows muscle wasting and obviates changes in myosin isoform expression during murine muscle disuse

Muscle wasting is a prominent feature of several systemic diseases, neurological damage and muscle disuse. The contribution of calpain proteases to muscle wasting in any instance of muscle injury or disease has remained unknown because of the inability to specifically perturb calpain activity in vivo. We have generated a transgenic mouse with muscle-specific overexpression of calpastatin, which is the endogenous inhibitor of calpains, and induced muscle atrophy by unloading hindlimb musculature for 10 days. Expression of the transgene resulted in increases in calpastatin concentration in muscle by 30- to 50-fold, and eliminated all calpain activity that was detectable on zymograms. Muscle fibres in ambulatory, transgenic mice were smaller in diameter, but more numerous, so that muscle mass did not differ between transgenic and non-transgenic mice. This is consistent with the role of the calpain-calpastatin system in muscle cell fusion that has been observed in vitro. Overexpression of calpastatin reduced muscle atrophy by 30 % during the 10 day unloading period. In addition, calpastatin overexpression completely prevented the shift in myofibrillar myosin content from slow to fast isoforms, which normally occurs in muscle unloading. These findings indicate that therapeutics directed toward regulating the calpain-calpastatin system may be beneficial in preventing muscle mass loss in muscle injury and disease.

Non-NASA Center↗