61 research outputs found
Ferulic Acid: Therapeutic Potential Through Its Antioxidant Property
There has been considerable public and scientific interest in the use of phytochemicals derived from dietary components to combat human diseases. They are naturally occurring substances found in plants. Ferulic acid (FA) is a phytochemical commonly found in fruits and vegetables such as tomatoes, sweet corn and rice bran. It arises from metabolism of phenylalanine and tyrosine by Shikimate pathway in plants. It exhibits a wide range of therapeutic effects against various diseases like cancer, diabetes, cardiovascular and neurodegenerative. A wide spectrum of beneficial activity for human health has been advocated for this phenolic compound, at least in part, because of its strong antioxidant activity. FA, a phenolic compound is a strong membrane antioxidant and known to positively affect human health. FA is an effective scavenger of free radicals and it has been approved in certain countries as food additive to prevent lipid peroxidation. It effectively scavenges superoxide anion radical and inhibits the lipid peroxidation. It possesses antioxidant property by virtue of its phenolic hydroxyl group in its structure. The hydroxy and phenoxy groups of FA donate electrons to quench the free radicals. The phenolic radical in turn forms a quinone methide intermediate, which is excreted via the bile. The past few decades have been devoted to intense research on antioxidant property of FA. So, the present review deals with the mechanism of antioxidant property of FA and its possible role in therapeutic usage against various diseases
Successful management of multiple permanent pacemaker complications – infection, 13 year old silent lead perforation and exteriorisation following failed percutaneous extraction, superior vena cava obstruction, tricuspid valve endocarditis, pulmonary embolism and prosthetic tricuspid valve thrombosis
A 59 year old man underwent mechanical tricuspid valve replacement and removal of pacemaker generator along with 4 pacemaker leads for pacemaker endocarditis and superior vena cava obstruction after an earlier percutaneous extraction had to be abandoned, 13 years ago, due to cardiac arrest, accompanied by silent, unsuspected right atrial perforation and exteriorisation of lead. Postoperative course was complicated by tricuspid valve thrombosis and secondary pulmonary embolism requiring TPA thrombolysis which was instantly successful. A review of literature of pacemaker endocarditis and tricuspid thrombosis along with the relevant management strategies is presented. We believe this case report is unusual on account of non operative management of right atrial lead perforation following an unsuccessful attempt at percutaneous removal of right sided infected pacemaker leads and the incidental discovery of the perforated lead 13 years later at sternotomy, presentation of pacemaker endocarditis with a massive load of vegetations along the entire pacemaker lead tract in superior vena cava, right atrial endocardium, tricuspid valve and right ventricular endocardium, leading to a functional and structural SVC obstruction, requirement of an unusually large dose of warfarin postoperatively occasioned, in all probability, by antibiotic drug interactions, presentation of tricuspid prosthetic valve thrombosis uniquely as vasovagal syncope and isolated hypoxia and near instantaneous resolution of tricuspid prosthetic valve thrombosis with Alteplase thrombolysis
Specificity analysis of sera from breast cancer patients vaccinated with MUC1-KLH plus QS-21
The mucin MUC1 is expressed on breast cancers in an underglycosylated form compared to normal tissues and is therefore a potential target for cancer immunotherapy. MUC1 contains multiple tandem repeats of the 20 amino acid (aa) peptide (VTSAPDTRPAPGSTAPPAHG). The APDTRPA epitope is particularly immunogenic since it is recognized by a variety of murine monoclonal antibodies and by some sera and cytotoxic T-cells from unimmunized patients with epithelial cancers. We have prepared a 30 aa peptide (C)VTSAPDTRPAPGSTAPPAHGVTSAPDTRPA with cysteine at the N-terminal end, and used the cysteine for chemical conjugation to keyhole limpet haemocyanin (KLH). Six breast cancer patients immunized with this conjugate plus the immunological adjuvant QS-21 have all produced high titre (by ELISA) IgG and IgM antibodies against the 30 aa MUC1 peptide, but these sera reacted moderately, or not at all, with MUC1-positive tumour cells. To understand this specificity better, we prepared a series of smaller peptides to determine the epitopes recognized by these immune sera in inhibition assays. Only peptides containing APDTRPA at the C-terminal end were able to completely inhibit ELISA reactivity for the full 30 aa peptide. No sera were completely inhibited by APDTR, APDTRP, PDTRPA or any other peptides that did not contain the full APDTRPA epitope. Remarkably, sera from all six patients recognized this same epitope and were completely inhibited by only this epitope. The specificity of these sera (1) primarily for C-terminal APDTRPA, and the absence of this epitope at the C-terminal end of any tumour mucins, and (2) the N-terminal APDTRPA alanine, which is normally buried in the β turn MUC1 assumes in its secondary structure may explain the moderate to weak reactivity of these high titer sera against MUC1-positive tumour cells. © 1999 Cancer Research Campaig
Fitness-for-Service Evaluation of Thermal Hot Spots and Corrosion Damage in Cylindrical Pressure Components
Fitness-for-Service Evaluation of Thermal Hot Spots and Corrosion Damage in Cylindrical Pressure Components
Thermal hot spots and corrosion damage are typical of damages occurring in pressure vessels and piping. Structural integrity of such components needs to be evaluated periodically to determine “fitness-for-service” (FFS) of the components. In the present paper, three alternative methods for level 2 FFS assessments (as described in API 579) are proposed. They are based on variational principles in plasticity, the m-alpha method, the idea of reference volume, and the concept of decay lengths in shells. Decay lengths in the axial and circumferential directions for cylindrical shells are derived based on elastic shell theories. They are used to specify the reference volume participating in plastic action and the extent of what can be called “local” damage. Interaction between longitudinal and circumferential effects is investigated. A linear interaction curve is shown to give good estimation of the “remaining strength factor” for damage of practical aspect ratios. The stretching and bulging effects due to the damage are also studied. The limit defining the threshold to dominance of stretching action is proposed by using an approximate equilibrium calculation based on yield-line analysis. The effectiveness of the proposed assessments is demonstrated through an example and verified by level 3 inelastic finite element analysis.</jats:p
Measurement of intraperitoneal metabolites during hypothermic cardiopulmonary bypass using microdialysis
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