University of North Texas Health Science Center

About: University of North Texas Health Science Center is a education organization based out in Fort Worth, Texas, United States. It is known for research contribution in the topics: Population & Receptor. The organization has 2972 authors who have published 5401 publications receiving 153180 citations. The organization is also known as: UNT Health Science Center & UNTHSC.

Analysis of oxidative modification of proteins.

Abstract: Proteins are targets of oxidative modification. This unit describes detailed procedures for the analysis of popular indices of protein oxidation including protein carbonyl formation, loss of protein thiols, and nitrotyrosine and dityrosine formation, as well as isoaspartate formation. Procedures are detailed for the analysis of protein carbonyls labeled with 2,4-dinitrophenylhydrazine, tritiated sodium borohydride, and biotin-hydrazide, followed by detection measurements that are based on the distinguishing feature of each labeling chemical. Methods are outlined for the determination of protein cysteine oxidation by quantifying the loss of free protein thiols using radiolabeled [(14)C]-iodoacetamide. Protocols are described for the measurement of protein dityrosine by gas chromatography/mass spectrometry, as are the details for the detection of protein nitrotyrosine by a competitive ELISA approach. Finally, methods are described for the quantification of protein-bound isoaspartate using protein-L-isoaspartyl methyltransferase that converts aberrant L-isoaspartyl residues in peptides and proteins to normal aspartyl residues.

Liquid Biopsy for Cancer: Review and Implications for the Radiologist

Abstract: Imaging and image-guided procedures play an imperative role in the screening, diagnosis, and surveillance of cancer. Although emerging imaging techniques now enable more precise molecular characterization of tumors, multigenetic tumor profiling for targeted therapeutic selection remains limited to direct tissue acquisition. Even in the context of targeted therapy, tumors adapt to acquire resistance. This necessitates serial monitoring, traditionally through tissue acquisition, to identify the molecular mechanism of resistance and to guide second-line therapy. An alternative to tissue acquisition is the collection of circulating tumor markers such as cell-free nucleic acids and circulating tumor cells in the peripheral blood. This noninvasive diagnostic approach is referred to as the liquid biopsy. The liquid biopsy is currently used clinically for therapeutic guidance when tissue acquisition is impossible or when the specimen is inadequate. It is also being studied in the context of screening, diagnosis, and surveillance. As cancer treatment continues to move toward a focus on precision medicine, this developing technology may alter and/or augment the role of imaging in the management of cancer. This review aims to outline the use of liquid biopsy in cancer and its potential impact on diagnostic imaging and image-guided procedures.

Glutamate receptor activation evokes calpain-mediated degradation of Sp3 and Sp4, the prominent Sp-family transcription factors in neurons.

Abstract: Sp-family transcription factors (Sp1, Sp3 and Sp4) contain a zinc-finger domain that binds to DNA sequences rich in G-C/T. As assayed by RT-PCR analysis of mRNA, western-blot analysis, immunofluorescence, and antibody-dependent "supershift" of DNA-binding assays, the prominent Sp-family factors in cerebral neurons were identified as Sp3 and Sp4. By contrast, glial cells were found to express Sp1 and Sp3. We previously showed that the pattern of G-C/T binding activity of Sp-family factors is rapidly and specifically altered by the calcium influx accompanying activation of glutamate receptors. Here, we demonstrate that Sp-factor activity is also lost after a cerebral ischemia/reperfusion injury in vivo. Consistent with its calcium-dependent nature, we found that glutamate's effect on Sp-family factors could be blocked by inhibitors of calpains, neutral cysteine proteases activated by calcium. Purified calpain I cleaved Sp3 and Sp4 into products that retained G-C/T-binding activity, consistent with species observed in glutamate-treated neurons. These data provide details of an impact of glutamate-receptor activation on molecular events connected to gene expression.