Monday, April 1, 2013

Issue 1, 2006

This issue and the next are all about the SENS 2005 meeting. I'm still going by the abstracts though, since that's the best I've got.

Section 1: Stem Cells and Regeneration

"Conjecture: Can Continuous Regeneration Lead to Immortality? Studies in the MRL Mouse". Separate summary since I found the article and it sounded interesting

"Sustained Stromal Stem Cell Self-Renewal and Osteoblastic Differentiation During Aging". Characterisation of a line of stem cells isolated in bone marrow that can differentiate into all (?) other types. Frequency decreases from 0.01% of bone marrow cells when 3 years old to 0.0018% at 45 but doesn't go down after that. Interesting but probably too basic-sciency to incorporate.

"To Make a New Intestinal Mucosa". Grabbed some rats, chopped a quarter of their small intestine, making them leak bile in their shit, grabbed intestinal stem cells from newborn rats, and combined them with a separate bit of cleaned up section of intestine (from different rats I assume), and inserted the reformed bit at the end of their small intestines. Worked (as in no more bile leakage). They also did some other experiment with plastic scaffolds and being able to look at the implanted cells in vivo. It all sounds interesting.

"Transfection of CCE Mouse Embryonic Stem Cells with EGFP and BDNF Genes by the Electroporation Method".  They show they can insert genes into stem cells by electroporation of plasmids and have them expressed.

"Glucose-Induced Replicative Senescence in Mesenchymal Stem Cells". Calorie restriction experiment in-vitro in which the mesenchymal stem cells which get less sugar die less and have higher replicative potential.


Section 2: Cancer, Cell Senescence, and Telomeres

"Gene Therapy That Safely Targets and Kills Tumor Cells Throughout the Body". Separate summary.

"Catechin-Vanilloid Synergies with Potential Clinical Applications in Cancer". Combination of two molecules inhibit expression of tNOX which is a molecule supposedly expressed only in cancers, and supposedly necessary for cancer growth.

"Multilocus Genotypes Spanning Estrogen Metabolism Associated with Breast Cancer and Fibroadenoma". Analysis of correlations between multiple SNPs associated with estrogen and breast cancer and fibroadenoma. They think they found something that increases risk 25 times. Study of 2500 people.

"Analysis of Telomere Length and Telomerase Activity in Tree Species of Various Lifespans, and with Age in the Bristlecone Pine Pinus longaeva". They compare telomere length and telomerase activity of bristlecone pines, which live for thousands of years to shorter lived trees. They think there's something there.

"Mitochondrial Dysfunction and Cell Senescence: Cause or Consequence?". Look at evidence of mitochondria's role in senescence. They say it's complicated. Sounds interesting but can't find it.

"Chromatin Modification and Senescence: Linkage by Tumor Suppressors?". Investigation of chromatin-modification path to senescence and potential genes involved. Maybe interesting.


Section 3: Neurodegeneration

"Amyloid-Beta Immunotherapy for the Prevention and Treatment of Alzheimer Disease: Lessons from Mice, Monkeys, and Humans". Seems to be a review of the experiments that have been performed in attacking amyloid beta through immunotherapy.

"Synaptic Pathology in the Brain Cortex of Old Monkeys as an Early Alteration in Senile Plaque Formation".  Measurements of synaptic density in old monkeys compared to adult monkeys. I don't understand the measurements, except for the one where it says that the number of synapses per neuron go down by about 20% in the temporal cortex, but not in the frontal cortex.

"Membership in Genetic Groups Predicts Alzheimer Disease". Allele group analysis correlations with Alzheimer's. They think they found something with 800 times risk. 300 people in study.

"Level and Distribution of Microtubule- Associated Protein-2 (MAP2) as an Index of Dendritic Structural Dynamics". More comparison of measurements between the brains of old rats and adult rats that I don't understand.

"Association Between the HLA-A2 Allele and Alzheimer Disease". They find that 46% of their study group with AD have the HLA-A2 allele vs 38% of controls.

"Structural Synaptic Remodeling in the Perirhinal Cortex of Adult and Old Rats Following Object-Recognition Visual Training". And yet more measurements comparing synaptic densities in old and adult rats. This time, it is after the rats learn something.

"The nACHR4 594C/T Polymorphism in Alzheimer Disease". Analysis of correlations between variants of the neuronal nicotinic acetylcholine receptor and AD. Study of 140.


Section 4: Immunosenescence

"Immunorejuvenation in the Elderly". About possible ways to restore the immune system from its cytomegalovirus obsession by killing those T-cells, regrowing the thymus and hammering CMV with drugs. Sounds interesting but I can't find it.

"Antibody Quality in Old Age". So supposedly, the specificity of antibodies produced against antigens decreases with age. They think this is due to laxer selection in the germinal centers of mucosal tissue.

"Immunomodulatory Vaccines Against Autoimmune Diseases". Description of therapeutic vaccines against multiple sclerosis and myasthenia gravis, an autoimmune neuromuscular disease.

"A Novel Approach to Thymic Rejuvenation in the Aged". They implant cells that produce interleukin-7 into old thymus and it seems to help. Another one that sounds interesting but that I cannot find.

"Biology of Longevity: Role of the Innate Immune System". Seems to be a review of the links between the immune system and longevity. Could be interesting. Hard to tell from the abstract. Can't find it anyway.

"Memory B Cell Subpopulations in the Aged". Lower blood levels of IgD in the blood of old people, higher level of CD19+CD27+ memory cells. Negative correlation between the two. Too many memory cells, not enough naive.

"Analysis of Candidate Genes in Celiac Disease: A Tool to Identify Life-Threatening Associated Genes?" They find no difference in the frequencies of the transforming growth factor beta 2 alleles between celiac disease patients, healthy patients and healthy people over 95 year old.

"Analysis of HLA-DQA, HLA-DQB Frequencies in a Group of Sardinian Centenarians". No significant differences between observed and expected frequencies of HLA-DQA1 and HLA-DQB1 in centenarians.