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  • 作者:

    Previous studies have demonstrated the protective effect of hypoxic preconditioning on acute ce-rebral infarction, but the mechanisms underlying this protection remain unclear. To investigate the protective mechanisms of hypoxic preconditioning in relation to its effects on angiogenesis, we in-duced a photochemical model of cerebral infarction in an inbred line of mice (BALB/c). Mice were then exposed to hypoxic preconditioning 30 minutes prior to model establishment. Results showed significantly increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra at 24 and 72 hours post infarction, mainly in neurons and vascular endothelial cells. Hy-Hypoxic preconditioning increased vascular endothelial growth factor and CD31 expression in the ischemic penumbra and the expression of vascular endothelial growth factor was positively related to that of CD31. Moreover, hypoxic preconditioning reduced the infarct volume and improved rological function in mice. These findings indicate that the protective role of hypoxic preconditioning in acute cerebral infarction may possibly be due to an increase in expression of vascular endothelial growth factor and CD31 in the ischemic penumbra, which promoted angiogenesis.

  • 作者:

    We previously showed that the repair of bone defects is regulated by neural and vascular signals. In the present study, we examined the effect of topically appliedβ-nerve growth factor (β-NGF) on neurogenesis and angiogenesis in critical-sized bone defects iflled with collagen bone substi-tute. We created two symmetrical defects, 2.5 mm in diameter, on either side of the parietal bone of the skull, and filled them with bone substitute. Subcutaneously implanted osmotic pumps were used to infuse 10 μgβ-NGF in PBS (β-NGF + PBS) into the right-hand side defect, and PBS into the left (control) defect, over the 7 days following surgery. Immunohistochemical staining and hematoxylin-eosin staining were carried out at 3, 7, 14, 21 and 28 days postoperatively. On day 7, expression of β III-tubulin was lower on theβ-NGF + PBS side than on the control side, and that of neuroiflament 160 was greater. On day 14,β III-tubulin and protein gene product 9.5 were greater on theβ-NGF + PBS side than on the control side. Vascular endothelial growth factor expression was greater on the experimental side than the control side at 7 days, and vascular endothelial growth factor receptor 2 expression was elevated on days 14 and 21, but lower than control levels on day 28. However, no difference in the number of blood vessels was observed between sides. Our results indicate that topical application ofβ-NGF promoted neu-rogenesis, and may modulate angiogenesis by promoting nerve regeneration in collagen bone substitute-iflled defects.

  • 作者:

    Experimental, clinical and epidemiologic studies have provided strong evidence that physical training has beneficial effects on cardiovascular health. Numerous investigations have demonstrated that exercise increases coronary blood flow and myocardial perfusion. Importantly, training also can stimulate angiogenesis and accelerate collateral vessel growth in animal models with coronary artery occlusion. Cardiac adaptation such as increased vascularity or capillary density has been evidenced after regular endurance exercises. More recently, several studies indicate that physical training induces high levels of myocardial heat shock protein and antioxidant protein expression, which may play an important role in myocardial protection against ischemia-reperfusion injury.

  • 作者:朱洪生;连锋;郑家豪

    Objectives. To observe the effect of basic fibroblast growth factor (bFGF) slow-release microcapsules on angiogenesis in infarcted myocardial regions.Methods. Myocardial infarction was induced in 24 New Zealand rabbits by ligating the root of left anterior descending coronary artery. Group Ⅰ (n = 8) served as control, group Ⅱ (n = 8) as a blank microcapsule group, group Ⅲ (n = 8, each microcapsule contains lμg bFGF) as micrpcapsule group. In group Ⅱ and Ⅲ, 5 blank microcapsules or bFGF slow-release microcapsules were implanted into myocardium underneath the epicardium between the left antefior descending coronary artery and left circumflex artery. Infarct size was evaluated by infarcted weight/left ventricle weight ratio and angiogenesis was evaluated by immunohistochemical examinations 5 weeks later.Results. As compared with group Ⅰ and Ⅱ, rabbits treated with bFGF slow-release microcapsules showed higher microvessel counts (group Ⅰ 37.75 + 4.50, group Ⅱ 38.37 ± 4.98, vs. group Ⅲ 135.50 ± 4.81, P < 0. 001 ) and less infarcted weight/left ventricle weight (group Ⅰ 16.8% ± 0.4%, group Ⅱ 16.7% ± 0.5%, vs. group Ⅲ 7.0% ±0.2% ,P< 0.001).Conclusions. Subepicardial administration of bFGF slow-release microcapsule in the infarcted rabbit model results in effective angiogenesis and reduction in infarct size.

  • Presenilin-1 Asp385 is Indispensable for Neurogenesis,Angiogenesisand β-amyloid Production

    作者:TAN Yan;XIA Dan;SHEN Jie;HUA Qian

    Objective:Presenilin(PS)is one of major causative genes of early onset familial Alzheimer's disease(FAD),which accounts for 95% of genetic factors. Presenilin-1(PS1)is considered as the catalytic subunit of theγ-secretase complex that cleaves type Ⅰ transmembrane proteins,such as amyloid precursor protein(APP),a protein closely related with AD. One conserved aspartate residue (Asp385)in PS1 is thought to constitute the active site of γ-secretase. In vitro,D385A mutation (the aspartate to alanine alteration)leads to the failure of PS1 endoproteolysis and abolishment ofγ-secretase activity. To further investigate the role of Asp385 residue in PS1 in vivo,we generated PS1 D385A knockin(KI)mice,in which an Asp385Ala(D385A)alteration was introduced in the genomic Psen1 locus. Method:The gene-editing method of Cre-LoxP has been used to generate PS1 D385A KI mice;southern blot has been used to detect the genomic DNA from both embryonic stem(ES)cells and mouse tails to confirm its genotype. Northern and western have been used to test the mRNA and protein levels of PS1. Morphology and the proliferation of neural progenitor cells of developing brains has been test by HE staining and BrdU immunohistochemistry. Angiogenesis has been test by both western and immunofluorescence to target the marker of vascular endothelial cells,CD31. In vitro γ-secretase assay has been used to test the activity of γ-secretase. Results:Homozygous D385A KI(KI/KI)mice display severe developmental deficits,including abnormal skeleton development,perinatal lethality,cerebral hemorrhages,enlarged lateral ventricle and massive loss of neural progenitor cells,which is identical to those of Psen1-null mice. D385A mutation dose not interrupt the level of Psen1 mRNA,but disrupt PS1 endoproteolysis. The N- and C-terminal fragments of PS1 are absent,and PS1 holoprotein accumulates(~18-fold)in KI/KI mice relative to the wild type(WT)controls. In addition,D385A mutation abolishesγ-secretase activity in the brain of D385A KI/KI mice,and the activity is significantly reduced in KI/+ mice. Furthermore,compared with WT mice,the protein level of CD31 is significantly increased in KI/+ mice within development and adulthood. In adult,KI/+ mice also show abnormal angiogenesis in both cortex and hippocampus, and cerebrovascular amyloid plaques have been detected in 10 month age. Conclusion:Collectively, these results demonstrate that the Asp385 of PS1 is indispensable for its function in maintaining normal development,neurogenesis,and γ-secretase activity. Furthermore,D385A mutation causes abnormal angiogenesis and amyloid plaques in vessels in adulthood.

  • The effectiveness of the mononuclear fraction of autologous bone marrow in the treatment of experimental chronic limb ischemia

    作者:Anzhelika Yu.Orlova;Elena B.Artyushkova;CUI Wei;Boris S.Sukovatyh;CUI Jing-zhen

    Objective To study of the effectiveness of using autologous mononuclear fraction of bone marrow for the treatment of chronic limb ischemia.Methods Results of autologous mononuclear fraction of bone marrow in 90 laboratory Wistar rats on a background of creating chronic limb ischemia was presented.Sampling was carried out from the bone marrow of the femur of the animal.The mononuclear fraction of bone marrow autologous 4 × l06 cells in a volume of 200 microliter were injected into the ischemic limb of the two points,in each of which 100 microliter:①Paravessel directly below the inguinal ligament at the level of the sacroiliac joint in the area of the anatomical location of collaterals in the projection of the internal iliac artery and its branches;② Intramuscularly in gastrocnemius muscle anterior-lateral surface of the middle third of the leg.Results In the experimental group of rats treated with autologous mononuclear fraction of bone marrow,the level of microcirculation compared with the intact group of animals on day 21 was higher than 6.1% by day 28% ~ 31.2%;compared with the control group-day 10 increased by 111% at day 21,85.7% on day 28% ~97%.Conclusion Proposed method of treating pathogenically justified and can be recommended for use in clinical practice in the treatment of patients with chronic obliterating diseases of lower limb arteries.

  • 作者:

    Angiogenesis is a very complex physiological process, which involves multiple pathways that are dependent on the homeostatic balance between the growth factors (stimulators and inhibitors). This tightly controlled process is stimulated by angiogenic factors, which are present within the tumor and surrounding tumor-associated stromal cells. The dependence of tumor propagation, invasion and metastasis on angiogenesis makes the inhibitors of new blood vessel formation attractive drugs for treating the malignancies. Angiogenesis can be disrupted by several distinct mechanisms:by inhibiting endothelial cells, by interrupting the signaling pathways or by inhibiting other activators of angiogenesis. This strategy has shown therapeutic beneift in several types of solid tumors, leading to Food and Drug Administration (FDA) approval of anti-angiogenic agents in the treatment of kidney, non-small cell lung, colon and brain cancers. Although no angiogenesis inhibitors have been approved for patients with metastatic prostate cancer, therapies that target new blood vessel formation are still an emerging and promising area of prostate cancer research.

  • 作者:

    Objective:The aim of this study was to investigate the ef ect of grape proanthocyanidins (GPC) on the growth and angiogenesis of hepatocellular carcinoma H22 cells xenograft in mice. Methods:The xenograft model was established using injected subcutaneously H22 cells into the right axil a of the mice. Each group was treated with dif erent doses of GPC and Endostar. Al these treatments were maintained for 10 days, and mice were sacrificed. The xenograft tumors in mice were measured. The proliferation activity level of H22 cells was determined by MTT assay, and the levels of vascular endothelial growth factor (VEGF) protein were examined by immunohistochemistry. Results:When treated with 50, 100 and 200 mg/kg of GPC and Endostar, the tumor inhibition rates were 13.17%, 23.37%, 36.15%and 14.71%, respectively. The tumor weight of xenograft was significantly lighter in high GPC group than the control group (P<0.05). The ODs in GPC groups were 0.835, 0.666 and 0.519, respectively. The absorbances in middle and high GPC groups were statistical y significant, compared with control group (P<0.01). Immunohistochemical technique showed the expression of VEGF of the GPC groups was down-regulated significantly compared with the control group (P<0.01). Conclusion:GPC can inhibit the growth of hepatocellular carcinoma H22 cellxenograft in mice. The inhibition of angiogenesis by the down-regulation of VEGF expression may play a key role in the anti-neoplastic ef ect of GPC.

  • 作者:

    Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor in adults. Standard therapeutic approaches provide modest improvement in the progression-free and overall survival, necessitating the investigation of novel therapies. We review the standard treatment options for GBM and evaluate the results obtained in clinical trials for promising novel approaches, including the inhibition of angiogenesis, targeted approaches against molecular pathways, immunotherapies, and local treatment with low voltage electric fields.

  • 作者:

    Optical spectroscopy devices are being developed and tested for the screening and diagnosis of oral precancer and cancer lesions. This study reports a device that uses white light for detection of suspicious lesions and green-amber light at 545 nm that detect tissue vascularity on patients with several suspicious oral lesions. The clinical grading of vascularity was compared to the histological grading of the biopsied lesions using specific biomarkers. Such a device, in the hands of dentists and other health professionals, could greatly increase the number of oral cancerous lesions detected in early phase. The purpose of this study is to correlate the clinical grading of tissue vascularity in several oral suspicious lesions using the IdentafiH system with the histological grading of the biopsied lesions using specific vascular markers. Twenty-one patients with various oral lesions were enrolled in the study. The lesions were visualized using IdentafiH device with white light illumination, followed by visualization of tissue autofluorescence and tissue reflectance. Tissue biopsied was obtained from the all lesions and both histopathological and immunohistochemical studies using a vascular endothelial biomarker (CD34) were performed on these tissue samples. The clinical vascular grading using the green-amber light at 545 nm and the expression pattern and intensity of staining for CD34 in the different biopsies varied depending on lesions, grading ranged from 1 to 3. The increase in vascularity was observed in abnormal tissues when compared to normal mucosa, but this increase was not limited to carcinoma only as hyperkeratosis and other oral diseases, such as lichen planus, also showed increase in vascularity. Optical spectroscopy is a promising technology for the detection of oral mucosal abnormalities;however, further investigations with a larger population group is required to evaluate the usefulness of these devices in differentiating benign lesions from potentially malignant lesions.

  • 作者:

    Bone is a highly vascularized tissue, although this aspect of bone is often overlooked. In this article, the importance of blood flow in bone repair and regeneration will be reviewed. First, the skeletal vascular anato-my, with an emphasis on long bones, the distinct mechanisms for vascularizing bone tissue, and methods for remodeling existing vasculature are discussed. Next, techniques for quantifying bone blood flow are briefly summarized. Finally, the body of experimental work that demonstrates the role of bone blood flow in fracture healing, distraction osteogenesis, osteoporosis, disuse osteopenia, and bone grafting is examined. These results illustrate that adequate bone blood flow is an important clinical consideration, particularly during bone regeneration and in at-risk patient groups.

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