Topic 1 — Telomere Biology & Telomerase (~3 pages equivalent)

1. Structure — TTAGGG repeats, T-loop, G-quadruplex, shelterin complex (TRF1, TRF2, RAP1, TIN2, TPP1, POT1) with functions of each
2. End-replication problem — why chromosomes shorten with each division, Hayflick limit, p53-mediated senescence/apoptosis
3. Telomerase holoenzyme — TERT, TERC, dyskerin, NHP2/NOP10/GAR1, TCAB1; step-by-step mechanism; regulation (MYC, sex hormones, tumor suppression)
4. Telomere attrition and aging — telomere clock hypothesis, in vivo correlations, cancer reactivation (TERT promoter mutations), ALT pathway
5. Telomeropathies — genetics (17+ genes, X-linked/AR/AD, anticipation), dyskeratosis congenita, aplastic anemia, IPF, MDS/AML; diagnosis (flow-FISH, NGS); treatment (androgens, HSCT, lung transplant)

Topic 2 — Free Radical Injury (~3 pages equivalent)

1. ROS generation — mitochondrial ETC leak, Fenton/Haber-Weiss reactions, NADPH oxidase (respiratory burst), ionizing radiation, CYP450, xanthine oxidase
2. Types of ROS — detailed table of O₂•⁻, H₂O₂, •OH, ONOO⁻, HOCl with production, removal, and pathologic effects
3. Antioxidant defenses — SOD (Cu/Zn and Mn isoforms), catalase, glutathione peroxidase, peroxiredoxins, vitamins E/C, GSH, metal sequestration proteins
4. Pathological effects — lipid peroxidation (initiation → propagation → termination, MDA/4-HNE), protein oxidation (carbonylation, cross-linking, enzyme inactivation), DNA damage (8-oxoG, SSBs/DSBs)
5. Disease applications — ischemia-reperfusion, radiation injury, CCl₄/acetaminophen/alcohol hepatotoxicity, atherosclerosis (oxLDL, foam cells), Parkinson/Alzheimer/ALS, aging (Harman theory)
6. Biomarkers and therapeutic targets with a summary table