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.
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 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.
ObjectiveTo observe the efficacy of different administration of conbercept on choroidal neovasculature (CNV) in patients with pathological myopia (PM).MethodsA retrospective case-control study. From June 2012 to June 2017, 57 patients (61 eyes) with PM-CNV diagnosed in the Ophthalmology Department of General Hospital of Central Theater Command were included in this study. All patients underwent BCVA, intraocular pressure, refractive index, slit lamp microscope, FFA, OCT examination and axial length (AL) measurement. An international standard vision chart was used in the BCVA test, which was converted to logMAR vision. According to the initial treatment plan, the patients were divided into 1+PRN treatment group (group A) and 3+PRN treatment group (group B), with 27 patients (31 eyes) and 30 patients (30 eyes), respectively. There was no significantly statistical difference in baseline data between the two groups (P＞0.05). The eyes was injected with 10 mg/ml of conbercept 0.05 ml (including conbercept 0.5 mg). After completion of initial treatment, on-demand treatment was performed according to repeated treatment standards. The average follow-up time was 30.8 months. The time point for curative effect determination was 24 months after treatment. The frequency and recurrence rate of vitreous cavity injections in the two groups of patients and the changes of BCVA, central macular thickness (CMT), diopter and AL were compared and observed. Continuous variables were compared between groups by independent sample t test. Categorical variables were compared by χ2 test. logMAR BCVA and injection frequency were compared by Wilcoxon rank test. Comparison of CMT before and after treatment was performed by paired t test.ResultsAfter 24 months, the number of intravitreal injections in group A and group B were 3.94±1.88 and 4.83±1.72, respectively, with statistically significant difference (Z=－2.182, P=0.029). After completion of initial treatment, the number of retreatments in group A and group B were 2.94±1.88 and 1.83±1.72, respectively, with significantly statistical different (Z=－2.330, P=0.020). The CNV recurrence rates were 38.71% and 13.33%, respectively, with statistically significant difference (χ2=5.074, P=0.024). Compared with prior treatment, the average BCVA at 1, 3, 6, 12, and 24 months after treatment significantly increased in group A and B (Group A: Z=5.634, 5.367, 5.532, 6.344, 6.135l; P＜0.05. Group B: Z=5.809, 5.090, 5.341, 5.939, 8.103; P＜0.05). At 1, 3, 6, and 12 months after treatment, there was no statistically significant difference in the average BCVA of the two groups (Z=－0.966, －0.932, －0.523, －1.759; P=0.334, 0.351, 0.601,0.079); the difference was statistically significant at 24 months (Z=－2.525, P=0.012). Compared with CMT before treatment, the difference in the average CMT reduction of the eyes in groups A and B was statistically significant at 1, 3, 6, 12, and 24 months (Group A: t=4.691, 2.624, 2.121, 1.921, 2.237; P＜0.05. Group B: t=4.947, 4.554, 5.290, 5.567, 5.314; P＜0.05); the average CMT comparison between the two groups was not statistically significant (P=0.457, 0.871, 0.505, 0.333, 0.798). During the follow-up period, there were no ocular complications and systemic adverse reactions.ConclusionsDifferent administration methods for the treatment of PM-CNV by intravitreal injection of conbercept are safe and effective, which can effectively improve BCVA and reduce CMT. Total injection of 3+PRN is more than 1+PRN. However, the injections of retreatment and CNV recurrence rate is lower, and the final follow-up vision is better.
Objective To evaluate the effect of vascular endothelial growth factor (VEGF) on tumor angiogenesis, and its usage in tumor therapy.Methods The recent literatures about VEGF and angiogenesis were reviewed and analyzed. The advances of VEGF study were summarized. The effects of anti-angiogenesis in tumor biological therapy were introduced.Results Angiogenesis had been identified as an important factor for promoting tumor growth. VEGF was a basic and pivotal factor in tumor angiogenesis. The anti-angiogenesis treatments aimed at VEGF, including the applications of VEGF inhibitor and gene therapy of adenovirus medium, had got great progress. Conclusion VEGF is a leading factor of tumor angiogenesis, the anti-angiogenesis therapy aimed at VEGF has probably provided a new chance to malignant tumor treatment.
Objective To compare the features of OCT angiography (OCTA) between neovascular age-related macular degeneration (nAMD) and myopic choroidal neovascularization (mCNV) patients before and after intravitreal anti-VEGF treatment. Methods A prospective cohort study. Twenty-nine patients (37 eyes) with nAMD (19 males and 10 females, aged 68.20±8.76) and 31 patients (34 eyes) with mCNV (9 males and 22 females, aged 43.10±11.80, with the mean diopter of −9.71±1.20 D) from Department of Ophthalmology, West China Hospital of Sichuan University during May and December 2017 were included in this study. Ranibizumab or Conbercept (0.5 mg/0.05 ml) was intravitreally injected in all eyes. The patients were follow-up for 3−6 months. The OCTA was conducted before treatment and 1 day, 1 week, 1 month and 3−6 months after treatment. In order to ensure that the scanning position was the same, the tracking mode was adopted for each scanning. According to the OCTA images, the lesion area, parafoveal superficial vessel density and perfusion area were measured and analyzed contrastively between nAMD and mCNV patients. Results The mean lesion area before and 1 month after treatment in nAMD patients were 0.38±1.87 mm2 and 0.06±0.12 mm2, while in mCNV patients, those were 0.26±1.06 mm2 and 0.03±0.05 mm2, respectively. There were statistically significant differences (Z=4.181, 4.475; P＜0.001) in CNV lesion area before and 1 month after treatment between nAMD and mCNV patients. Compared with those before treatment, the absolute change (Z=1.853, P=0.064) and the percentage changes (t=2.685, P=0.010) of CNV lesion area 1 month after treatment in nAMD and mCNV patients show a statistical meaning. There were significantly decreases in both parafoveal superficial vessel density (F=8.997, P=0.003) and perfusion area (F=7.887, P=0.015) 3 months after treatment in nAMD patients, while decreases in parafoveal superficial vessel density (F=11.142, P=0.004) and perfusion area (F=7.662, P=0.013) could be detected 1 day after treatment in mCNV patients, before rising 1 month after treatment. Conclusions There are significantly differences in lesion area before and after the treatment of intravitreal anti-VEGF between nAMD and mCNV patients by OCTA examination. Moreover, the changes of both parafoveal superficial vessel density and perfusion area after anti-VEGF treatment are statistically different in two groups.
ObjectiveTo observe the effect of preoperative intravitreal ranibizumab injection (IVR) on the operation duration of vitrectomy and postoperative vision for the treatment of proliferative diabetic retinopathy (PDR). MethodsA prospective study was carried out with the 90 PDR patients (90 eyes) who underwent vitrectomy. The 90 patients(90 eyes)were assigned to the vitrectomy only group(43 eyes) and the IVR combined with vitrectomy group (47 eyes). The IVR was performed 5-13 days prior to vitrectomy in the IVR combined with vitrectomy group. There were 15 eyes with fibrous proliferation PDR (FPDR), 16 eyes with advanced PDR (APDR) without involving the macular and 16 eyes with APDR involving the macular in the vitrectomy only group. There were 14 eyes with FPDR, 15 eyes with APDR without involving the macular and 14 eyes with APDR involving the macular patients in the IVR combined with vitrectomy group. All the eyes in the two groups were regularly operated by the same doctor to complete the vitrectomy. The start and end time of vitrectomy were recorded. The average follow-up time was 10 months. The changes of best corrected visual acuity (BCVA) before and 1, 3 and 6 months after surgery were compared between the two groups. ResultsThe duration of operation of the FPDR type (t=-8.300) and the APDR involving the macular type (t=-2.418) in the IVR combined with vitrectomy group was shorter than vitrectomy only group (P < 0.05). The comparison of duration of operation of the APDR without involving the macular type in the two groups has no statistically significant difference (t=-1.685, P > 0.05). At 1 month after surgery, the comparison of BCVA of the IVR combined vitrectomy group and the vitrectomy only group in APDR involving the macular type has no statistically significant difference (t=0.126, P > 0.05). At 3, 6 months after surgery, the BCVA of the IVR combined vitrectomy group in APDR involving the macular type was significantly better than the BCVA of the vitrectomy only group (t=8.014, 7.808; P < 0.05). At 1, 3, and 6 months after surgery, the BCVA of the IVR combined vitrectomy group in FPDR type (t=3.809, 1.831, 0.600) and APDR without involving the macular type (t=0.003, 1.092, 3.931) compared with pre-treatment, the difference were not statistically significant (P > 0.05); the BCVA in APDR without involving the macular type compared with pre-treatment, the difference was distinctly statistically significant (t=2.940, 4.162, 6.446; P < 0.05); the BCVA in APDR involving the macular type (t=0.953, 1.682, 1.835) compared with pre-treatment, the difference were not statistically significant (P > 0.05). ConclusionPreoperative IVR of PDR can shorten the operation duration and improve the BCVA of APDR involving the macular type.