August 30, 2012
Cholesterol efflux pathway regulates hematopoietic stem cell and progenitor cell mobilization
Intact cholesterol metabolic balance, help maintain hematopoietic stem cells and multi-progenitor cells (HSPC) in the resting state. Cross the cell membrane transporter cholesterol adenosine triphosphate-binding cassette transporter factors ABCA1 and ABCG1 defects can lead to the mouse cell cholesterol efflux pathway barriers.
Such mice showed a dramatic increase in HSPC mobilization and extramedullary hematopoiesis. The extramedullary hematopoiesis dramatic increase is caused due to splenic macrophages and dendritic cells to produce IL-2-induced increase in serum G-CSF levels.
The extramedullary hematopoiesis increase to promote the differentiation of bone marrow hematopoietic lineages decided to granulocytes, and not inclined to the direction of the macrophage differentiation. This damages the support of the osteoblasts and mesenchymal progenitor the cells produce Cxcl12/SDF-1 factor reduction.
Increased high-density lipoprotein levels the Abca1-/-Abcg1-/- and ApoE-/ - mice and FLT3-ITD mutation-mediated myeloproliferative neoplasms in the mouse model, a strong mobilization of HSPC and extramedullary hematopoiesis the reversal. Of FLT3 (FMS-like tyrosine kinase, of FMS-like tyrosine kinase 3) belongs to the type III receptor tyrosine kinase (receptor tyrosine kinase III, RTK III) family members, In recent years, many studies have demonstrated large sample of FLT3 activation mutations play an important pathological role in the occurrence and progression of the disease in AML.
The data of this study is to determine the cholesterol efflux pathway HSPC mobilization has control. This is likely to translate into atherosclerosis and treatment strategies for hematologic malignancies.
Posted by: biomichael825 at
06:27 AM
| No Comments
| Add Comment
Post contains 241 words, total size 2 kb.
August 24, 2012
Anxiety disorders and premature aging are directly related totelomere shortening
In August 13, 2012 News / biological Valley BIOON / - anxiety disorders and premature aging-related? Recently, researchers from Brigham and Women's Hospital (BWH) reveals a common form of anxiety disorders such as our common fear of anxiety in middle-aged and older women, anxiety disorders, and telomere shortening. This study reveals the the fear anxiety may accelerate aging risk factor.
The research results published in the international journal PLoS One recently.
The telomere (Telomeres) is a DNA-protein complexes of the ends of chromosomes, can protect the chromosome from deterioration, and the telomeres also the chromosomes during cell division end guards protect genetic information; however telomere biology and cellular senescence markers , shortened telomere length and increased risk of cancer, heart disease and other illnesses directly related.
In this large cross-sectional study, researchers from the age of 5243 in the 42-69 year-old women who get their blood samples, analysis of samples, the researchers analyzed the telomere length, At the same time, participants also fill out a questionnaire about their terror anxiety. The analysis results show that the high levels of phobic anxiety and significant telomere shortening related and phobic anxiety women telomere length and the normal group.
The researcher Olivia said, a lot of people want to know whether the pressure, how to make aging rapidly, it is noteworthy that this study also explains a common form of psychological pressure (phobic anxiety) and premature aging of the relationship between. However, the study design can not prove cause and effect or what the problem first occurred, anxiety occurs first or telomere shortening occurs first, is unknown.
In summary, this study later studies telomeres shorten anxiety paved the way, and provide some basis.
Posted by: biomichael825 at
02:06 PM
| No Comments
| Add Comment
Post contains 290 words, total size 3 kb.
August 04, 2012
Special acetyltransferase recognition provides new idea for the development of mosquito-killing agent
Recently, researchers from the
University of Wisconsin, etc. found in the insect the key structural component
of an enzyme that plays multiple roles, including the role of the synthesis of epidermis and melatonin ,and biogenic
amines detoxification. And this enzyme is active in aedes aegypti, which is
known as the disseminator of yellow fever and dengue fever..The study results
were published in a recent journal PNAS.
Researcher Jianyong Li and his
colleagues studied this enzyme – fragrant alkyl amine N-acetyl transferase
(aaNAT). Using bioinformatics techniques to divided the insect sequence which
is similar to aaNAT into three clusters, and then using crystallographic
techniques, the team observed three clusters of enzymes in the crystal
structures, and finally found that the biochemical active component of the
protein from the two clusters enzymes. It is worth
noting that the research team found a unique cluster of enzymes in the mosquito.
Next ,the researchers will further
study the physiological function of this particular enzyme in mosquitoes.In
short, the researchers' findings provides a basis for the biochemical function study
of the mosquitoes specific enzymes,and provides ideas and guidance for the development
of a potential mosquito-killing agent.
Posted by: biomichael825 at
06:33 AM
| No Comments
| Add Comment
Post contains 203 words, total size 2 kb.
August 03, 2012
Zinc finger nucleases can penetrate the cell membrane in protein form
Recently, a study published in Nature Methods concluded that ,the zinc finger nuclease (ZFN) modifying the target genome can penetrate the cell membrane in the form of protein, which will make ZFN delivery process easier and more secure.
Designed Nuclhease suc as ZFN, can make multiple types of genome produce specific changes, which help to support researches and gene therapy. Nuclease is also delivered into the cell in the form of DNA or RNA, and then produce a functional protein.
Carlos Barbas reported that they observed in several mammalian cells and found ZFN proteins penetrate the cell membrane. When ZFN protein inside the cell reaches a high enough concentration, it will produce a specific genomic changes, which effect is similar to that ZFN is delivered in DNA form. Previously ,people thought that only a small portion of protein and peptide involved in the cell membrane permeation, but now must take ZFN into account.
Compoaired with ZFN delivery in DNA form, the ZFN-protein exists in the target cells for only a short period ,and off-target effects on changes in the genome is much lower. Protein delivery can avoid the risk of virus insertion mutation in the delivery process, and the cell poisoning risk produced when cells response to exogenous DNA.
Posted by: biomichael825 at
05:25 PM
| No Comments
| Add Comment
Post contains 220 words, total size 2 kb.
German found a bacterial toxin that can lead to cell suicide
German researchers found that a bacterial toxin can cause a protein inactivation within the cell, resulting in cell "suicide". This finding helps to study how to kill cancer cells. Related paper was published in "Journal of Biological Chemistry".
Germany University of Freiburg, issued a press statement on August 1 that, university researchers found a kind of toxincalled "Tpel†in Clostridium perfringens, which can lead to gas gangrene. The toxin can cause sugar molecules attached to Ras proteins in the host cell to interfere with the natural functions of this protein.
Pharmacologist Klaus, Aketorresfrom University of Freiburg told us that , Ras protein in human cells play an important role in stimulating cell growth, the toxin Tpel will change this protein to fail to promote cell growth, ultimately leading to cell death.
It often occurs Ras protein mutation In human cancer cells, and this protein plays an important role in cancer formation.If target the variant Ras protein in the cells, and we can perhaps use such toxins lead to cancer cells "suicide." The researchers are now conducting further studies.
Posted by: biomichael825 at
09:26 AM
| No Comments
| Add Comment
Post contains 189 words, total size 2 kb.
20kb generated in CPU 0.0083, elapsed 0.0753 seconds.
32 queries taking 0.0694 seconds, 51 records returned.
Powered by Minx 1.1.6c-pink.
