Skip to main content

Home/ RIS IB Biology/ Contents contributed and discussions participated by chanon chiarnpattanodom

Contents contributed and discussions participated by chanon chiarnpattanodom

chanon chiarnpattanodom

Chimeric green fluorescent protein-aequorin as bioluminescent Ca2+ reporters at the sin... - 1 views

    • chanon chiarnpattanodom
       
      Experiment on Ca2+ reaction with a protein aequorin. Aequorin can be found in jellyfish, when in contact with Ca2+ will emit light. Using the gene that contributes to this protein, make a similar protein emitting another wavelength of light.
chanon chiarnpattanodom

Cancer epigenetics takes center stage - 1 views

    • chanon chiarnpattanodom
       
      DNA methylation is a chemical process where a methyl group is added on either the cytosine ring or the adenine ring, used in "higher leveled" organisms. Important in cell differentiation since methylation will cause cells to "remember" and remain differenciated instead of expressing other genes. 
  • Epigenetics is defined as modifications of the genome, heritable during cell division, that do not involve a change in the DNA sequence.
  • Epigenetic alterations in cancer include global hypomethylation
  • ...18 more annotations...
  • the promoters of housekeeping genes that are generally protected from methylation.
  • may lead to aberrant silencing of tumor suppressor genes
  • discovered loss of imprinting (LOI) in cancer
  • Genomic imprinting, the subject of the report by Nakagawa et al. (2), is an epigenetic modification of a specific parental allele of a gene, or the chromosome on which it resides, in the gamete or zygote, leading to differential expression of the two alleles of the gene in somatic cells of the offspring.
  • we found that LOI can occur in the normal colonic mucosa of colorectal cancer patients with LOI in their tumors
  • This LOI was linked to cases showing microsatellite instability (MSI) in the tumors
  • However, these patients do not have mutations in mismatch repair genes
  • One potential cause of MSI in these sporadic cancers is hypermethylation and epigenetic silencing of the hMLH1 mismatch repair gene
  • Nakagawa et al. (2) now confirm the original study of Cui et al. that LOI occurs in both tumor and normal tissue of patients
  • The present study (2) also offers an intriguing mechanistic hypothesis to explain the relationship between H19 DMR methylation and LOI in these patients
  • Nevertheless, the study calls attention to this remarkable highly conserved multifunctional protein,
  • The potential link to CTCF suggested by this study also calls our attention to the link among DNA methylation, epigenetics, and chromatin.
  • A clue to the link between MSI and epigenetics may be provided by another sometimes overlooked common thread in epigenetics, namely DNA replication
  • repeat-induced gene silencing is thought to be propagated through hemimethylated intermediates during DNA replication
  • The studies of Cui et al. (11), Nishihara et al. (20), and Nakagawa et al. (2) suggest a new and provocative view of the timing of epigenetic changes in cancer.
  • Studies of transgenic mice with constitutive biallelic expression of IGF2, comparable to LOI, show reduced apoptosis and increased tumor formation
  • I conclude by noting that the distinction between cancer genetics and epigenetics has blurred considerably in recent years
  • Many conventional “genetic” mechanisms directly affect proteins that regulate chromatin,
chanon chiarnpattanodom

Parallel Genetic and Phenotypic Evolution of DNA Superhelicity in Experimental Populati... - 0 views

  •  
    Importance of DNA supercoiling affects on E coli's growth, parallel and creating beneficial mutations.
chanon chiarnpattanodom

A new class of obesity genes encodes leukocyte adhesion receptors - 0 views

  •  
    Obesity is controlled by a number of factors, mainly 2 factors genetics and the environment. Here they use 2 groups + 1 control group mice to compare obesity.
chanon chiarnpattanodom

Genes an important factor in urinary incontinence - 1 views

  •  
    Scientists have studied how much is urinary incontinence controlled by genetics, rather than the environment by observing twins. 
chanon chiarnpattanodom

Genes an Important Factor in Urinary Incontinence - 1 views

  •  
    Scientists have studied how much is urinary incontinence controlled by genetics, rather than the environment by observing twins. 
chanon chiarnpattanodom

Stem cell therapy could repair some heart damage - Yahoo! News - 2 views

  • Patients with advanced heart disease who received an experimental stem cell therapy
  • Study authors described the trial as the largest to date to examine stem cell therapy as a route to repairing the heart in patients with chronic ischemic heart disease and left ventricular dysfunction.
  • injections of their own stem cells, taken from their bone marrow, into damaged areas of their hearts.
  • ...11 more annotations...
  • The patients -- 82 of whom were men -- all had chronic heart disease, along with either heart failure or angina or both, and their left ventricles were pumping at less than 45 percent of capacity.
  • None of the participant
  • eligible for revascularization surgery
  • heart disease was so advanced
  • Those who received the stem cell therapy saw a small but significant boost in the heart's ability to pump blood, measuring the increase from the heart's main pumping chamber at 2.7 percent more than placebo patients.
  • However, other factors showed no improvement
  • heart's maximum oxygen consumption did not change
  • defects in the heart were not healed by the treatment
  • This is the kind of information we need in order to move forward with the clinical use of stem cell therapy," said lead investigator Emerson Perin
  • "With this mapping procedure, we have a roadmap to the heart muscle," said Perin
  • Heart disease is the leading killer in the United States, claiming nearly 600,000 lives per year, according to the US Centers for Disease Control and Prevention.
  •  
    A recent experiment was done on elderly patients who had heart diseases, those that had progressed too far for coronary surgery. Patients were injected with their own stem cells in the bone marrow into areas in the heart. The pumping capacity did improve a little, but overall the oxygen use and the defects did not change. This is a stepping stone towards using stem cells to treat people in difficult situations where a normal surgery would not.
chanon chiarnpattanodom

HHMI Bulletin February 2012: The Twists and Turns of Immunity - 4 views

    • chanon chiarnpattanodom
       
      Immune System-System the signals the creation of millions of antibodies that RECOGNIZE invading molecules
1 - 8 of 8
Showing 20 items per page