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samedi, septembre 29 2012

Pathological cardiac hypertrophy

The cardiac hypertrophy features include myocardial cells increase in size, contractile protein content increased myocardial cells and embryonic ? like gene reactivation. Zhao et cardiomyocytes cultured in serum-free matrix GGF2 (20ng ml) were incubated 72h, neonatal rat ventricular myocytes increased significantly and was class myofibrillar like changes; embryonic gene atrial natriuretic peptide ANFmRNA expression and cardiac actin mRNA (under normal circumstances, only showed a low level of expression), incubated for 16h increased nearly 2-fold; GGF2 incubation of H leucine incorporation increased, and increased myocardial protein synthesis. In cultured adult rat ventricular myocytes, GGF2 can cause hypertrophic-like reaction, GGF2 continued for 72h, rat myocardial cells began to grow! Pseudopodia ?-like protrusions to five days, more than 60 percent of the adult rat ventricular muscle cells showed hypertrophy phenotypic changes. The body of the original mRNA applications GGF2 (20ng ml), myocardial atrial natriuretic peptide 1 in 60min, 20h within 3 to 4 times. Applications GGF2 after 7h, actin mRNA began to increase 250%, 30h, than adrenergic quasi agent phenylephrine induced actin mRNA increased more significantly. GGF2 dose-dependent induction of 3H leucine incorporation increased GGF2 concentration was increased by 70% when 5ng ml. All results show that, NRG fat large changes in phenotype can be induced in the neonatal and adult rat ventricular myocytes. Baliga NRG1 (a soluble recombinant human GGF2) in cultured neonatal rat cardiomyocytes also observed a similar reaction.

lundi, septembre 10 2012

NRG ErbB role in angiogenesis

1998 Russell et al in matrix culture without growth factor in human umbilical vein endothelial cells (HUVEC), the addition of recombinant NRG 3 (a ErbB3 ErbB4 ligand) culture 10d, found that NRG 3 (100ng ml) allows the number of HU VEC an increase of 25 times with 10ng ml the effect of vascular endothelial growth factor (VEGF). Applications can significantly inhibit VEGF-stimulated cells increase in the number of anti-VEGF antibody, but not affect NRG 3 due to the number of HUVEC increased, indicating that NRG 3 HUVEC proliferation effect has nothing to do with VEGF. HUVEC, its application of the two-dimensional collagen gel matrix culture by adding 24 ~ 36h after NRG 3 lumen-like structures formed lengthwise in HUVEC, will not affect the anti-VEGF antibody NRG this angiogenic effect. Corneal angiogenesis model in rats applications containing different doses of NRG or VEGF sustained-release tablets implanted eyes of 7d found, 10ngNRG can induce new blood vessel formation, 50ng can significantly promote new blood vessel formation; role of VEGF similar but does not rely on VEGF. Bagheri is found that The HRG stimulate of breast cancer the epithelial cells VEGFmRNA and protein expression, adding HRG1 to 9hVEGFmRNA increased 2-6 times, can stimulate endothelial cells to produce luminal-like structure, the application of anti-HER2 monoclonal antibody or anti-VEGF monoclonal antibodies this effect can be blocked, this angiogenesis is VEGF dependent. Yen also observed in other tumor cells to a similar result.

mardi, septembre 4 2012

The NRG ErbB the cardiovascular effects

The role of experiments in heart development, the NRGs, ErbB2 and ErbB4 an important role in the development of the nervous system and the heart. NRG ErbB promote the proliferation of cardiomyocytes, hypertrophic growth inhibition of cardiomyocyte apoptosis and promote cell survival. GGF2 to promote embryonic rat neonatal rat cardiac myocytes DNA synthesis, and promote an increase in the number of myocardial cells. A net increase of the number of functional myocardial cells in the embryonic heart development process, related with the proliferation of myocardial cells, is still associated with myocardial cell survival. Study also observed that nearly 25% of the cells in serum-free matrix in primary cultures of neonatal rat cardiac myocytes number 4d died; contrary, a 30% increase in the number of cells added GGF2 GGF2 promote survival of cardiomyocytes in vitro . Expression the no function NRGs and ErbBs rats died of heart and nervous system abnormalities in the uterus. NRG1, ErbB2, ErbB3, ErbB4 is no function of the mutated gene experiments showed that embryonic mice, mutations in several other genes outside than ErbB3 and development 10. 5d, due to poor cardiac differentiation, lack of ventricular trabeculae and endocardial cushion while resulting in the death of the embryo. Hertig application NRG1 and insulin-like growth factor diffuses into the chambers of the heart found, NRG1 can promote the formation of trabecular ventricular wall, and insulin-like growth factor 1 had no effect. In addition, NRG1 and insulin-like growth factor 1 synergistically induced cardiomyocyte DNA synthesis, and promote the growth of the ventricular tight zone and AV cushion after two heart chamber development and maturation of the key. Prompt the NRG1 and insulin-like growth factor 1 interaction occurs affect the morphology of the heart chamber. Zhao et GGF2 with other pro-mitogen not identical, in serum-free low density alkylene fusion myocardial cell culture, GGF2 mechanism to promote the survival of neonatal and adult cardiomyocytes, in part is due to inhibition of apoptosis.

mercredi, août 29 2012

NRG4 only expressed in mature cells of the pancreas, which showed low levels of expression in muscle cells

The cardiovascular system NRG ErbB widely expressed in the cardiovascular system, but differences in their distribution in different tissues. Mainly distributed in the intima of developing ventricular NRG1mRNA, NRG2 mRNA is mainly distributed in the intima of developing atrial NDF (neu 1mR NA) expression in rat coronary microvascular endothelial cells in cardiac development and pathological hypertension are induced cardiac hypertrophy, myocardial cells and neighboring endothelial cells highly expressed NRGs. While rat embryonic development of the mid-ErbB2, ErbB3 and ErbB4 expression After ErbB3 expression was significantly down-regulated. ErbB2, ErbB4 distribution in atrial and ventricular myocardium, ErbB3 distributed in the mesenchymal cells in the endocardial cushion and Cordis ball. In human umbilical vein endothelial cells detected immune response kind of ErbB2, ErbB3 and ErbB4 Nervous system and other tissues in the nervous system of the neurons, astrocytes, oligodendrocytes, glial cells and Schwann cells receptor expression are ErbBs. Retinal neurons, breast cancer cells have NRGs distribution. Peripheral listen ganglion and vestibular ganglion ARIR highly expressed. NRG4 only expressed in mature cells of the pancreas, which showed low levels of expression in muscle cells.

dimanche, août 26 2012

Neuromodulation prime

Neuromodulation prime NRGs by six different domains: the amino-terminal region of the immunoglobulin-like domain, EGF-like domain, the juxtamembrane sequence of the transmembrane sequence and cytoplasmic domain. The NRGs existence of different forms of soluble and membrane chimeric. Most of the the NRGs First synthesis and membrane-bound precursor proN RGs proNRGs followed to produce soluble NRGs, and secretion of this form. NRGs may play a role in cell paracrine autocrine form. ErbBs receptors ErbBs receptors membrane receptor, its structure consists of an extracellular binding site domain, a transmembrane domain, a tyrosine kinase domain and a C-terminal domain. The ErbBs receptor subtypes may form homo-or heterodimer, dimer functions and constitute a dimer receptor subtypes to stimulate the ligand and is activated in the intracellular signal transduction pathways related

mercredi, août 22 2012

Neuromodulation and Its ErbBs receptors in the cardiovascular system

Neuregulin (Neuregulins, NRGs), a member of the epidermal growth factor (EGF) family, a local role of polypeptide regulatory factors, plays an important role of the nervous system, such as NRGs promote the proliferation of Schwann cells and glial cells, differentiation adhesion, migration, and survival. Known NRGs, NRG1, NRG2, NRG3 and NRG4 four subtypes. The NRG1 Department with a gene encoding a product separation and purification and cloning in different laboratories, it is a different name, such as neu differentiation factor (of neu differentiationfactor NDF), human heregulin (HRG), glial growth factor (GGF) and acetylcholine the re ceptor inducing the activity (ARIA). In addition, three different genes encoding other types of neuregulin, respectively, NRG2, NRG3 and NRG4. Functional receptors for NRGs ErbBs, also known as epidermal growth factor receptor (EGFR), including four subtypes: ErbB1 of EGFR, ErbB2 of HER2 of neu of ErbB3 of HER3 and ErbB4 is HER4. NRGs and ErbBs receptor activation of the ErbB receptor tyrosine kinase induced by a wide range of biological effects, such as cell proliferation, differentiation, migration, adhesion, survival. Recent studies have shown that NRG of ErbB signaling pathway also plays an important role in the development process of the cardiovascular system, and to participate in the pathogenesis of cardiac hypertrophy. Neuromodulation prime NRGs by six different domains: the amino-terminal region of the immunoglobulin-like domain, EGF-like domain, the juxtamembrane sequence of the transmembrane sequence and cytoplasmic domain. The NRGs existence of different forms of soluble and membrane chimeric. Most of the the NRGs First synthesis and membrane-bound precursor proN RGs proNRGs followed to produce soluble NRGs, and secretion of this form. NRGs may play a role in cell paracrine autocrine form.

lundi, juillet 9 2012

basic fibroblast growth factor

The skin is the body's largest organ, has a complex structure and function. The skin tissue engineering in vitro construction of tissue engineered skin substitutes is the best solution for the treatment of skin defects. But this skin substitute is transplanted into the skin defect in slow cell ingrowth and vascularization inadequate may result in poor graft survival, which will directly lead to graft failure, and may be further induced by infection and other complications. Therefore, many studies have focused on solving these two problems. Experiment acellular amniotic membrane scaffolds, gelatin - chitosan microspheres to achieve the basic fibroblast growth factor (Basic fibroblast growth factor, bFGF) in controlled release, both composite and then planted human fibroblasts . Intends to explore this approach to build a slow release of bFGF new artificial active dermal feasibility. Protein secreted by the cells, laminin has a clear role in promoting tissue vascularization. Can be seen in the blood vessels of the skin around the wound, high expression of laminin (LN), it can promote epithelial cell adhesion, migration and the formation of vessel-like structures. Detected by western blot into fiber cells of laminin found elevated expression in fibroblasts on acellular amniotic load of BFGF-gelatin - chitosan microspheres, indicating that this drug delivery particles can well bFGF sustainable and stable functioning. This experiment, because of acellular amniotic membrane pore size is smaller, not through the traditional liposuction or injections of bFGF-gelatin - chitosan microspheres load the acellular amniotic membrane, so the direct adhesion its theoretical foundation off the chemical composition of the cells on amniotic membrane, gelatin, chitosan, acellular amniotic membrane surface is soft, strong adhesion. The results showed that sustained release microspheres better adhesion and acellular amniotic membrane surface. Related Articles: Basic fibroblast growth factor

Build the artificial activity dermis acellular amniotic slow release of basic fibroblast growth factor

The amniotic membrane, placenta closest to the fetal surface of a thin film of tissue, mainly composed of three layers: the epithelial cell layer, the thick basement membrane and avascular stroma. Acellular amniotic membrane usually by mechanical methods or chemical method, but may have residual cells. The authors used detergent - enzyme digestion Preparation of acellular amniotic membrane residual cells and cytotoxic. After scanning electron microscopy measurements, the higher porosity, pore size is relatively small. The ideal tissue engineering scaffold material not only has a high porosity, and pore size, which is conducive to seed cells along stent "hole" long into the stent internal growth. Compared with normal skin, artificial skin, lack of vascular network system, which will lead to artificial skin graft failure. Can enhance the induction of graft transplantation of blood vessels in the body of to solve this problem. bFGF is a class with higher activity of poly-peptide, with a wide range of biological activity, can change the number of cell chemotaxis, induce or inhibit the synthesis or secretion of specific proteins. Some in vivo experiments confirmed that the wound healing process, the early parts of bFGF to the formation of a large number of new capillaries. Drug delivery system of drug compound in biological materials up to achieve a stable and slowly release become a hot research. In previous reports you can see the many different methods to build a drug delivery system. The authors used gelatin - load of bFGF in the chitosan microspheres with good encapsulation efficiency and drug loading, drug release curves to prove that such a delivery system to maintain a relatively stable concentration of drug action. Materials is the production of microspheres of gelatin and chitosan, two natural materials, good organization and cell compatibility, degradation products can be completely absorbed by the body, non-toxic and harmless, in line with the requirements of tissue engineering. Related Articles: Basic fibroblast growth factor

Basic fibroblast growth factor eye drops treatment of persistent corneal epithelial defects

Causes chemical burns, trauma, surgery, keratitis, persistent corneal epithelial defect is a common ocular surface disease, traditional treatment methods: bandage, wearing soft contact lens, eyelid suture, prime Jie treatment ointment, achieved certain results, but still not satisfied. From years to years of basic fibroblast growth factor eye drops treatment of cases, compared with prime high hormone therapy ointment treatment cases, and now the results are reported below. Certain area of the whole layer of epithelium (basement membrane) damage, and healing are known as continuous weeks or more, the disease can be caused by a variety of reasons, if not effectively treated, often can lead to corneal ulceration or melting, or even perforation, severe impact visual function. Although some effects to the traditional treatment methods, but still not ideal, so to find and develop new drugs to promote corneal epithelial healing, is an important topic to further improve the cure rate of the disease. bfgf the existence of a trace protein in the mammalian and human tissue, with a wide range of biological activity of a variety of mesodermal and neuroectodermal cells derived from experimental studies have confirmed, it can effectively stimulate in vitro animal and human corneal epithelial cells in the matrix into the fiber cells and endothelial cell proliferation, migration. Such as isolated from bovine pituitary, since the purified, people's general physical and chemical properties, distribution in tissues, the mechanism of action on the tissues and cells. A lot of research and molecular biological characteristics, biological effects and clinical use of security. Recombinant bovine eye drops used in this article Biological Pharmaceutical Co., Ltd. of Zhuhai East application of genetic engineering methods developed by the domestic production has gradually entered the industrialization and commercialization stage, and better meet the clinical and research needs. For clinical application of eye drops reported is still in trial stage, Guangzhou Medical College Huangjuan Deng reported that recombinant eye drops treatment of cases of corneal disease patients, cured patients, improved in the cases, the effective rate. This paper reports the recombinant eye drops treatment of cases, and Su Gao Jie treatment ointment treatment cases were compared, Results The total effective rate in the control group, there are significant differences. The best on the the limbus fence normal trauma, surgical cases efficacy; Second part of the chemical burn injury cases; keratitis are caused by the worst cases of efficacy. Affected by a combination of factors In addition to the factors of epithelial healing, tear quality and quantity changes and matrix damage. In short, non-toxic side effects of the reorganization of eye drops, safe and effective, and convenient, and effective treatment, it is recommended for clinical application. Related Articles: Basic fibroblast growth factor

samedi, mai 19 2012

human Neuregulin 1

Expected application ELISA quantitative determination people organization homogenate, cell culture in qing or other relevant biological NRG1 content in the liquid. The theory Use the purified antibody packet is porous plate, made from solid phase carrier, and went to fight NRG1 antibodies wrapped in micro hole in turn to join specimen or standard and biotin resistance of the NRG1 antibody, HRP mark and element, thoroughly after washing with the substrate TMB show color. TMB in peroxidase catalytic down into blue, and under the action of acid into final yellow. The color depth and samples of the NRG1 were positively correlated. YongMei standard instrument in the 450 nm wavelength were spectrophotometry (OD) values, calculate sample concentration. Kit composition and reagent preparation

Specimen collection and storage 1. The organization homogenate: animal tissue samples from first to use the PBS washing, remove excess blood, homogenate on 20 mlPBS change in 20 ° C placed in-at night, and the next day, after two times repeated freeze-thaw broken membrane, will homogenate content 5000 x g centrifugal 5 minutes, take the test on can be. 2. The thing on cell culture clear or other biological specimen: please 1000 x g centrifugal 20 minutes, take the test on can be, or the specimen is put in the-20 ? 80 ? or-preservation, but should avoid the repeated freeze-thaw. Note: the above samples 4 ? for preservation should be less than 1 week,-20 ? 80 ? or-all should be sealed save,-20 ? should not be more than a month,-80 ? should be no more than two months; Specimen hemolysis will affect the last test results, so hemolysis specimens should not be on this detection; High blood fat specimens to special processing, can directly measure the. Related Articles:Neuregulin 1