nov13th Flashcards
Excitotoxicity in stroke
Excitotoxicity is caused by extracellular glutamate accumulation leading to uncontrolled ion influx into neurons.
Neo-antigens in cancer
Neo-antigens are tumor-specific antigens arising from mutations and are targeted by immune checkpoint therapy.
PSI-BLAST profile
A profile in PSI-BLAST is made from a multiple alignment highlighting conservation at each position.
Cerebral organoids limitations
Human cerebral organoids are not suitable for studying sensory pain mechanisms.
Stem cell potency
Multipotent stem cells have higher differentiation capacity than oligopotent stem cells.
Inflammation in stroke
Inflammation after a stroke often exacerbates damage rather than promoting repair.
FASTA format
A FASTA file starts with ‘>’ followed by an identifier, with sequence data on subsequent lines.
Positive positions in BLAST
Positive positions refer to identical matches or conservative substitutions with a positive score.
Cancer heterogeneity
Most tumors are genetically heterogeneous with treatment-resistant subclones.
Telomerase activity
Telomerase adds repetitive sequences to chromosome ends, preventing shortening during replication.
Lynch syndrome
Lynch syndrome is caused by inherited MMR gene mutations, increasing cancer risk.
Trans-differentiation
Trans-differentiation converts one differentiated cell type directly into another.
Random mutations in cancer
Random mutations during DNA replication are a major contributor to cancer risk in high turnover tissues.
Organoids for neurodevelopment
Cerebral organoids are suitable for studying human neurodevelopment and neurological diseases.
ROS in stroke
Reactive oxygen species (ROS) accumulation causes cellular injury and neuronal death in ischemic stroke.
Checkpoint inhibitors
Immune checkpoint inhibitors block PD-1 or CTLA-4, restoring immune response against tumors.
Excitotoxicity mechanism
Overactivation of NMDA and AMPA receptors by glutamate leads to calcium influx and cell death.
Mismatch repair genes
MLH1, MSH2, MSH6, and PMS2 mutations are linked to Lynch syndrome.
PSI-BLAST iterations
PSI-BLAST refines searches iteratively using a position-specific scoring matrix (PSSM).
Profiles in PSI-BLAST
Profiles enhance sensitivity by highlighting conserved sequence features in multiple alignments.
Pluripotent vs multipotent
Pluripotent stem cells can differentiate into all body cell types except extra-embryonic tissues.
Multipotent stem cell examples
Multipotent stem cells include hematopoietic and mesenchymal stem cells.
Stem cell differentiation
Stem cell potency decreases from totipotent to pluripotent, multipotent, and oligopotent.
Sporadic vs hereditary cancer
Sporadic cancers arise from random mutations, while hereditary cancers involve germline mutations.
Neo-antigen definition
Neo-antigens are newly formed antigens resulting from somatic mutations in tumors.
False-negative PCR causes
Mismatched primers or low target DNA concentration can cause false-negative PCR results.
RNA modifications
tRNA modifications include methylation and pseudouridylation for stability and function.
Telomerase in cancer
Telomerase activation in cancer cells allows indefinite proliferation by maintaining telomere length.
CFTR compound heterozygosity
Compound heterozygosity involves two different CFTR mutations causing cystic fibrosis.
Heterozygous genotype calculation
For alleles with frequencies p and q, the heterozygous frequency is calculated as 2pq.
Immune tolerance
Immune tolerance prevents the immune system from attacking self-antigens.
