Fluorescence studies on the interaction of hydrophobic ligands with Momordica charantia (bitter gourd) seed lectin

The interaction of Momordica charantia (bitter gourd) seed lectin (MCL) with several nucleic acid bases has been investigated by monitoring changes induced in the protein fluorescence by ligand binding. Values of the binding constant, Ka were obtained as 1.1 × 104, 1.56 × 104 and 2.2 × 103 M−1 for adenine, cytosine and uracil, respectively. In addition, binding of 8-anilinonaphthalene 1-sulfonate (ANS) with MCL was investigated by fluorescence spectroscopy. Interaction with MCL at low pH results in a large enhancement of the fluorescence intensity of ANS with a concomitant blue shift in the emission λmax, whereas at neutral and basic pH changes in both fluorescence intensity and emission maximum were very small, clearly suggesting that the MCL-ANS interaction is stronger at lower pH values. When excited at 295 nm in the presence of ANS, the protein fluorescence decreased with a concomitant increase in the emission intensity of ANS, suggesting resonance energy transfer from the tryptophan residues of MCL to ANS. Gel filtration profiles of MCL at pH values 2.0 and 7.4 are similar indicating that the tetrameric nature of MCL is retained even at low pH. Addition of lactose or adenine to MCL-ANS mixture did not alter the change in ANS fluorescence suggesting that lactose, adenine and ANS bind to MCL at independent and non-interacting sites. These results are relevant to understanding the functional role of MCL in the parent tissue

Abstract Number ‐ 254: Yield of CTA in Patients over 50 with Brain Hemorrhages at Sites Typical for Hypertension

Introduction Approximately 10%–15% of acute strokes are spontaneous, nontraumatic intraparenchymal cerebral hemorrhage (IPH). Hypertension (HTN), amyloid angiopathy, or impaired coagulation cause most spontaneous IPHs, in which case the CTA is unlikely to identify an underlying vascular lesion. Prior investigators have identified clinical and non‐contrast CT (NCCT) features that increase the likelihood of identifying a vascular etiology for an IPH, including younger age (3 in only one patient). One was on subcutaneous heparin (PTT was 53). No other patient had major coagulation abnormalities; only 5 patients had platelets count < 100K, the lowest was 62K. CTA was negative for underlying vascular lesion at the site of bleeding in all 143 patients, confidence interval 2.6% using Confidence intervals for proportions, using Wilson’s method for proportions. Conclusions In patients over 50 year of age with evidence of hypertension, and ICH in the basal ganglia, thalamus, brain stem and cerebellum; the diagnostic yield of CTA is negligible. Performing this study routinely in the evaluation of these patient increases health care costs, and exposes patients to the risks of unnecessary radiation, contrast induced kidney injury and death. We recommend against the routine use of CTA in patients meeting the above criteria

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Not AvailableViperin, also known as radical S-adenosyl methionine domain-containing protein (RSAD2) is a multifunctional interferon-stimulated gene (ISG) that is activated during the viral infections. Viperin belongs to S-adenosyl methionine (SAM) superfamily of enzymes known to catalyze radical-mediated reactions and viperin inhibits a wide range of DNA and RNA viruses through its broad range of activity. The present study reports cloning and expression of bovine viperin in a bacterial expression system. PCR-based site-directed mutagenesis was carried out for deletion of N-terminal 1–70 amino acid containing amphipathic helix of viperin that interferes in protein expression and purification. The resultant truncated viperin protein was expressed in Escherichia coli, BL-21(DE3) competent cells and purified using nickel charged affinity column. The truncated 54 kDa protein was confirmed by western blot using human RSAD2 as a probe. Further, in house, hyperimmune serum was raised against the truncated viperin in the rabbit and the reactivity was confirmed by western blot using mammalian expression vector construct of viperin transfected in Baby Hamster kidney (BHK) cells and in MDBK cells infected with Foot and Mouth disease Asia I virus.Not Availabl

Association for Computational Linguistics: Human Language Technologies

[No abstract available