Objective To study the advances in microcirculation after islets of Langerhans transplantation (ILT). Methods The literature in the recent years on the study of the relationship between ILT and microcirculation was reviewed. Results The process of angiogenesis and revascularization of the islet grafts was in progress within 1 week after transplantation, and was completed within 10-14 days after transplantation, exhibiting a microangioarchitecture similar to pancreatic islets in situ. The sequence of vascular intraislet cellular perfusion was from β cells outward to α-and δ-cell cortex, with the majority of α cells perfused before the majority of δ cells. Freely transplanted islet grafts were revascularized from the hostderived microvascular bed. The interstitial pressure in the islet transplants was markedly lower than the capillary pressure. There were clearly differences in microcirculation between syngeneic and xenogeneic islet grafts. The phenomena of microcirculation failure were observed in xenografts. The influential factors of microcirculation after ILT were ①culture temperature of isolated islets, ②cultured time and cryopreserved method of islets, ③blood glucose, ④immunosuppressive agents, ⑤angiogenesis factors. Conclusion Microvascularization of freely islet grafts is one of the essential requirements for successful engraftment, guaranteeing sufficient nutritional blood supply to the tissue and establishing blood drainage for adequate liberation of the endocrine hormones. Through the studies of the microcirculation after ILT, it is helpful to recognize the mechanism of the survival of islet grafts.
Objective To study the relationships between expressions of somatostatin receptor subtypes(SSTR1-SSTR5) and angiogenesis in colorectal cancer. Methods The expressions of SSTR1-SSTR5, VEGF, and CD34 in the paraffin sections of colorectal cancer tissues from 127 cases were detected by the standard streptavidin-peroxidase (SP) technique. CD34 was used as a marker to account microvessel density (MVD) in colorectal cancer tissues. The relationships between the expressions of SSTR1-SSTR5 and VEGF expression, or MVD were analyzed. Results The positive expression rate of SSTR1, SSTR2, SSTR3, SSTR4, and SSTR5 was 64.6% (82/127), 36.2% (46/127), 18.9% (24/127), 18.9% (24/127), and 38.6% (49/127) in colorectal cancer tissues, meanwhile, the positive expression rate of VEGF was 63.8% (81/127) and MVD was (34.67±16.62)/HP in colorectal cancer tissues. The positive expression rate of VEGF (47.8%, 22/46) and MVD 〔(29.00±15.32)/HP〕 in colorectal cancer tissues with SSTR2 positive expression were significantly lower than those in colorectal cancer tissues with SSTR2 negative expression 〔72.8%, 59/81; (37.90±16.56)/HP〕, Plt;0.05. There were no relationships between SSTR1, SSTR3, SSTR4, and SSTR5 expression and VEGF expression or MVD (Pgt;0.05). Conclusion The positive expression of SSTR2 is related with angiogenesis in colorectal cancer tissues.
【Abstract】Objective To introduce the possible effect of endogenous angiogenesis inhibitive factors in the therapy of hepatocarcinoma. Methods Recent relevant literatures were reviewed. ResultsEndogenous angiogenesis inhibitive factors can suppress the growth of tumor blood vessels, which might head off the development and metastasis of hepatocarcinoma effectively. This might provide a new approach to the therapy of hepatocarcinoma. ConclusionRecent studies on endogenous angiogenesis inhibitive factors will be helpful in the prevention and treatment of hepatocarcinoma.
ObjectiveTo evaluate the macular visual function of patients with myopic choroidal neovascularization (MCNV) before and after intravitreal injection of conbercept.MethodsA prospective, uncontrolled and non-randomized study. From April 2017 to April 2018, 21 eyes of 21 patients diagnosed as MCNV in Shanxi Eye Hospital and treated with intravitreal injection of conbercept were included in this study. There were 9 males (9 eyes, 42.86%) and 12 females (12 eyes, 57.14%), with the mean age of 35.1±13.2 years. The mean diopter was −11.30±2.35 D and the mean axial length was 28.93±5.68 mm. All patients were treated with intravitreal injection of conbercept 0.05 ml (1+PRN). Regular follow-up was performed before and after treatment, and BCVA and MAIA micro-field examination were performed at each follow-up. BCVA, macular integrity index (MI), mean sensitivity (MS) and fixation status changes before and after treatment were comparatively analyzed. The fixation status was divided into three types: stable fixation, relatively unstable fixation, and unstable fixation. The paired-sample t-test was used to compare BCVA, MI and MS before and after treatment. The x2 test was used to compare the fixation status before and after treatment.ResultsDuring the observation period, the average number of injections was 3.5. The logMAR BCVA of the eyes before treatment and at 1, 3, and 6 months after treatment were 0.87±0.32, 0.68±0.23, 0.52±0.17, and 0.61±0.57, respectively; MI were 89.38±21.34, 88.87±17.91, 70.59±30.02, and 86.76±15.09, respectively; MS were 15.32±7.19, 21.35±8.89, 23.98±11.12, 22.32±9.04 dB, respectively. Compared with before treatment, BCVA (t=15.32, 18.65, 17.38; P<0.01) and MS (t=4.08, 3.50, 4.26; P<0.01) were significantly increased in the eyes 1, 3, and 6 months after treatment. There was no significant difference in the MI of the eyes before treatment and at 1, 3, and 6 months after treatment (t=0.60, 2.42, 2.58; P>0.05). Before treatment and at 1, 3, and 6 months after treatment, the proportion of stable fixation were 28.57%, 38.10%, 38.10%, 33.33%;the proportion of relatively unstable fixation were 47.62%, 47.62%, 52.38%, 57.14% and the proportion of unstable fixation were 23.81%, 14.28%, 9.52%, 9.52%, respectively. The proportion of stable fixation and relatively unstable fixation at 1, 3 and 6 months after treatment were higher than that before treatment, but the difference was not statistically significant (x2=1.82, 1.24, 1.69; P>0.05).ConclusionBCVA and MS are significantly increased in patients with MCNV after intravitreal injection of conbercept.
Objective To explore the inhibitory effects of r-k4k5 on retinal neovascularization. Methods Eighty-eight one-week-old C57BL/6J mice were put into the environment with 75% oxygen for 5 days to establish models of vascular proliferation retinopathy. One eye of each mouse received an intravitreal injection of 500 ng of r-k4k5 (large-dosage group) and of 250 ng of r-k4k5(small-dosage group), and the same volume of BSS was injected into the other eye of the mice both in these two groups as a control. The ADPase histochemical staining was used for retinal flatmount to observe changes of retinal vessels. The inhibitory effects of r-k4k5 on retinal neovascularization were evaluated by counting the endotheliocyte nuclei of new vessels extending from retina to vitreous in the tissue-slice. Results Regular distributions and reduced density of retinal blood vessels in eyes in the treatment group were found in retinal flatmount. The number of the endotheliocyte nuclei of new vessels extending from retina to vitreous was less in the eyes in the treatment group than which in control group (Plt;0.001). The nuclei of new blood vessels in the large-dosage group were less than which in small-dosage group (Plt;0.001). No histologic evidence of retinal toxicity or inflammatory response was found in the tissue-slice after the injection of r-k4k5. Conclusions Retinal neovascularization can be inhibited by intravitreal injection of r-k4k5,which suggests that intravitreal injection of r-k4k5 may have potential therapeutic benifits in retinal vascular disease. (Chin J Ocul Fundus Dis,2003,19:121-124)
In the expert consensus published by the Pediatrics in 2013, it was first proposed that anti-VEGF drugs can be considered for retinopathy of prematurity (ROP) with stage 3, zone Ⅰ with plus disease. However, there are many problems worth the attention of ophthalmologists, including the advantages and disadvantages of anti-VEGF therapy compared with traditional laser therapy, systemic and ocular complications after anti-VEGF therapy, and what indicators are the end points of anti-VEGF therapy. Combined with this consensus and numerous research findings, we recommend that the first treatment for anti-VEGF or laser therapy should be considered from disease control effects. For the threshold and pre-threshold lesions, the effect of anti-VEGF therapy for zoneⅡ lesions is better than that for zone Ⅰ lesions and the single-time effective rate is high. So, it is suggested that anti-VEGF therapy should be preferred for the first treatment. The choice of repeat treatment should be considered from the final retinal structure and functional prognosis. Laser therapy is advisable for the abnormal vascular regression slower and abnormalities in the posterior pole. It can reduce the number of reexaminations and prolong the interval between re-examinations. However, the premature use of laser has an inevitable effect on peripheral vision field. Excluding the above problems, supplemental therapy can still choose anti-VEGF therapy again. Most of the children with twice anti-VEGF therapy are sufficient to control the disease. Anti-VEGF therapy should be terminated when there are signs such as plus regression, threshold or pre-threshold lesions controlled without recurrence, peripheral vascularization, etc.
Objective To investigate the feasibility of intramuscular gene therapy for acute arterial ischemic diseases by use of plasmid pcDNA3-VEGF121 and to evaluate therapeutic efficiency of vascular endothelial growth factor(VEGF) by different routes of administration. Methods Fifty New Zealand White rabbits were randomly assigned to either gelation sponge carryingpcDNA3-VEGF121 (n=18), intramuscular injectionpcDNA3-VEGF121 (n=18), or pcDNA3 (as control group,n=14). After ligation of the external iliac artery and complete excision of the femoral artery, 500 μg of the plasmid pcDNA 3-VEGF121 were transfected into the muscles of the ischemic limb by gelation sponge carrying or direct intramuscular-injection. Immediately after gene transfection, blood flow of the internal iliac artery were measured. VEGF121gene expression was detected by RT-PCR after 2 days, 1 week, 2 weeks, 3 weeks and 4 weeks of transfection. After 30 days, blood flow of the internal iliac artery, angiographic score and histologicalvessels of ischemic hindlimbs were measured respectively. Results In the two VEGF-treated groups, VEGF121 mRNA expressed in the transfected ischemic muscles after 2 days and lasted 2 weeks. Immediately after gene transfection, blood flow of the internal iliac artery had no significant difference between three groups. After 30 days, blood flow of the internal iliac artery, angiographicscore and capillary density were significantly greater in both VEGF-treated groups than in control group. Complexity of vascular branching and vessel density of gelation sponge-VEGF treated limbs were significantly greater when comparedwith the intramuscular-injection limbs. Conclusion These findings suggest the feasibility of employing gene therapy of pcDNA3-VEGF121could augmentcollatal development and tissue perfusion in an animal model of hindlimb ischemia, andgelation sponge carrying VEGF gene may respect a potential therapy methods.
Objective To investigate the effect of combined therapy of granulocyte colony stimulating factor (G-CSF) and bone marrow mesenchymal stem cells (BMSCs) carrying hepatocyte growth factor (HGF) gene on the angiogenesis of myocardial infarction (MI) in rats and the mechanisms of the synergistic effect. Methods BMSCs were aspirated from the femur and tibia of 3-week-old Sprague Dawley (SD) male rats. The third generation of BMSCs were harvested and transfectedwith Ad-HGF. The MI models were establ ished in 44 SD male rats (weighing 200-250 g) by l igating the left coronary artery. At 4 weeks after l igation, the shorting fraction (FS) of the left ventricle being below 30% was used as a criteria of model success. The BMSCs (5 × 107/ mL) transfected with Ad-HGF were transplanted into the infarct zone of 12 SD rats, and the expression of HGF protein was detected by Western blot method at 2, 7, and 14 days after transplantation. At 4 weeks, the other 32 SD rats were randomly divided into 4 groups (n=8). The 0.1 mL normal sal ine was injected into the infarct zone in control group; 0.1 mL normal sal ine was injected combined with intraperitoneal injection G-CSF [100 μg/ (kg•d)] for 5 days in G-CSF group; 0.1 mL BMSCs (5 × 107/ mL) transfected with Ad-HGF was injected into the infarct zone in HGF group; 0.1 mL BMSCs (5 × 107/ mL) transfected with Ad-HGF was injected combined with intraperitoneal injection G-CSF [100 μg/ (kg•d)] for 5 days in combined therapy group. At 2 weeks after transplantation, heart function was detected by cardiac ultrasound and hemodynamic analysis, and then myocardial tissue was harvested to analyse the angiogenesis of the infarct zone, and the expression of VEGF protein by immunofluorescence staining. Results The expression of HGF protein in vivo was detected at 2 days and 7 days of BMSCs transfected with Ad-HGF transplantation. There was no significant difference in left ventricular systol ic pressure (LVSP), left ventricular end-diastol ic pressure (LVEDP), dP/dtmax, and FS between G-CSF group and control group (P gt; 0.05). When compared with the control group, LVEDP decreased significantly; LVSP, FS, and dP/dtmax increased significantly (P lt; 0.05) in HGF group and combined therapy group. When compared with HGF group, FS and dP/dtmax increased significantly in combined therapy group (P lt; 0.05). Immunofluorescence staining showed that the vascular endothel ial cells were observed in myocardial infarction border zone. The vascular density and the expression of VEGF protein were significantly higher in combined therapygroup than in other 3 groups (P lt; 0.05). Conclusion The combined therapy of G-CSF and BMSCs carrying HGF gene has a synergistic effect and can enhance infarct zone angiogenesis through inducing the expression of VEGF protein.
Objective To evaluate the role for integrins in tumor angiogenesis. MethodsLiteratures in recent years were reviewed. ResultsIntegrins played an important role in tumor angiogenesis and integrins had a close relation to vascular growth factors. Conclusion Inhibitors of integrins will be a promising way to cure tumors.