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.
【Abstract】Objective To study the change of pancreatic microcirculation in the early phase of acute pancreatitis. MethodsLiteratures on acute pancreatitis and microcirculation were collected and reviewed.ResultsPancreatic microcirculation has changed in the early phase of acute pancreatitis, including contraction of interlobular arteriole, slowing of blood fluid, increasing of pancreatic vascular permeability, leukocyte adherence in postcapillary venules, and decreasing of pancreatic perfusion.Conclusion Impairment of pancreatic microcirculation in the early phase of acute pancreatitis may play a key role in the progression of this disease.
The model of acut hemorrhagic necrotizing pancreatitis(AHNP)was produced by retrograde injection of 3% sodium taurocholate into the biliopancreatic duct.48rats with AHNP were treated with Tanshin by subcutaneous injection(100mg/100g body weight,q12h,tanshin group),48 rats with AHNP without any treatment as control(control group).The resule showed that in the control group,there were severe hemorrhage,necroses and the lesions of microvascular,the activity of pancreatic enzyme in serum increased significantly(Plt;0.01)at 6h,after 12h the activities of those pancreatic enzymes decreased gradually, the lesions of microvascular and histology were becoming severer.In the Tanshin group,at 24h the lesions of microvascular and histology of the pancreas were modified significantly (Plt;0.05).These results suggest that the lesion of microcirculation play an important role in the later AHNP,and Tanshin has some effects on the AHNP by modifying the microcirculation of the pancreas.
In order to investigate the survival mechanism and the role of venous drainage in arterialized venous skin flap, 60 rabbits’ ears were used for research and clinical application of the flap was performed subsequently in two cases. The rabbits were divided into 4 groups. Experimental group was standard arterialized venous skin flap, control 1 group was venous skin flap, control 2 group was arterialized venous skin flap with only one drainage vein and control 3 group was normal skin flap. The process of survival of the flaps was observed by hemodynamic and histological method. The results showed that there was no significant difference between standard arterialized venous skin flap and normal skin flap (P gt; 0.01). Two cases of arterialized venous skin flap survived completely. The conclusion were as follow: 1. the opening of collateral circulation between the veinlets was the main change of the microcirculation; 2. the blood flow of the graft was changed from unphysiological circulation to physiological circulation as the time elapsed and 3. amelioration of venous drainage was important in inproving the survival rate of arterialized vein graft.
Objective To investigate the relationship between gene expression of endothelin-3 (ET-3） and inflammation of acute pancreatitis （AP） in rats. Methods Fifty-four rats were divided randomly into 4 groups: sham operation group, AP group, arterial injection group and vein injection group. AP was induced by reverse intra-bile duct infusion 4.5% sodium taurocholate, treated with low dose dopamine 〔5 μg/（kg·min）〕 by injecting arterial or tail vein. Rats were sacrificed at 1， 6 and 24 h after the induction of AP. The mRNA expression of ET-3 was evaluated by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and pathological changes was observed in rats. Results Expression of ET-3 mRNA could be detected from 1 up to 24 h after the induction of pancreatitis. Expression of ET-3 mRNA of sham operation group was decreased significantly compared with other three groups. Expression of ET-3 mRNA showed a significant decrease by arterial injection dopamine than that by tail vein (P＜0.05， P＜0.01). The pathologic score in AP group was the highest, vein injection group was the next one, and score in sham operation group was the lowest. Conclusion There are significant relationship between inflammation of AP and expression of ET-3 mRNA. Dopamine administration by arterial injection is more effective than that by tail vein injection.
ObjectiveTo explore the effects of urinastatin(UTI) on microcirculation of extrapancreatic organs in rats with acute necrotizing pancreatitis(ANP). Methods A total of 48 rats were randomized into control group, ANP group and UTI group. The model of ANP was established by uniform injection of 5% sodium taurocholate solution under pancreatic capsule, only injection of normal saline in control group. Then the rats of UTI group were injected with UTI through the femoral vein, the rats of ANP group and control group were injected with normal saline. The blood flow of lung, kidney and distal small intestine was measured by radioactive biomicrosphere technique at 2 h and 6 h after ANP.ResultsCompared with the control group, the blood flow of lung, kidney and intestine was decreased significantly in the ANP group at the 2 h and 6 h after ANP （P＜0.05）, compared with the ANP group, the blood flow was increased significantly in UTI group （P＜0.05）. ConclusionMicrocirculation disorder is an important factor of the extrapancreatic organ damage in ANP, and UTI plays a protective role against microcirculation disorder of the extrapancreatic organ in ANP.
Anti-VEGF therapies have been widely used in the treatment of age-related macular degeneration, diabetic macular edema, retinal vein occlusion with macular edema and other retinal diseases. It have achieved remarkable treatment effect with relatively high safety, but there are still reports of adverse reactions in cardio-cerebral vessels and eyes. There are many methods to measure retinal blood flow. Although the principles of these methods are different, the results are different, and there is no uniform standard, it has been observed that anti-VEGF drugs may cause some changes in retinal vessel diameter, arterial blood flow velocity and blood flow parameters. Especially after multiple injections, the effect may be more obvious.
ObjectiveTo observe and analyze the effect of HbA1c level on macular microcirculation in patients with type 2 diabetes mellitus (T2DM).MethodsA cross-sectional study. One hundred and twenty-four T2DM patients (124 eyes) without diabetic retinopathy who diagnosed by the examination of fundus color photography in Lixiang Eye Hospital Of Soochow University during September to December 2017 were enrolled in this study. There were 59 males (59 eyes) and 65 females (65 eyes), with the mean age of 65.06±7.99 years old. All patients underwent BCVA, fundus color photography, and OCT angiography (OCTA). The history of diabetes, hypertension and dyslipidemia were recorded in detail. According to the HbA1c level, patients were divided into three groups, HbA1c ideal control group (group A, HbA1c ＜7%, 67 eyes), HbA1c control group (group B, 7%≤HbA1c≤9%, 44 eyes), and HbA1c poor control group (group C, HbA1c＞9%, 13 eyes), respectively. The 3 mm×3 mm range of the macular area was scanned by OCTA instrument. The vascular density (VD) and skeleton density (SD) of nonsegmented retinal layer (NRL), superficial retinal layer (SRL) and deep retinal layer (DRL) in the macular area and foveal avascular zone (FAZ) area, non-circularity index, axial rate (AR) of SRL were measured. The correlation between HbA1c, BCVA and VD, SD of NRL, SRL, DRL was analyzed statistically with Spearman correlation test. The correlation between systemic factors and the above indicators was analyzed statistically with linear regression analysis.ResultsThe results of linear regression analysis showed that HbA1c was significantly correlated with VD (t=?3.237, ?3.156, ?2.050) and SD (t=?0.3.45, ?3.034, ?2.248) of NRL, SRL and DRL (P＜0.05); but no correlation with FAZ, non-circularity index and AR (t=1.739, 0.429, 1.155; P＞0.05). The differences of VD (F=6.349, 5.981, 3.709), SD (F=7.275, 6.085, 1.904) and AR (F=0.027) of NRL, SRL and DRL in group A, B and C were statistically significant (P＜0.05); but the differences of FAZ (F=1.904), non-circularity index (F=0.280) was not statistically significant (P＞0.05). Significant differences (P＜0.05) of VD and SD of NRL were found between group A and B (t=1.987, 2.201), group A and C (t=3.365, 3.572), group B and C (t=2.010, 2.076). Significant differences (P＜0.05) of VD and SD of SRL were found between group A and B (t=2.087, 2.168), group A and C (t=3.197, 3.194). There were significant differences (P＜0.05) in SD of DRL between group A and B (t=2.239), group A and C (t=?2.519). There was significant difference in VD of DRL between group A and C (t=2.363). The results of Spearman correlation analysis showed that HbA1c was negatively correlated with VD (r=?0.273, ?0.255, ?0.222; P=0.002, 0.004, 0.013) and SD (r=?0.275, ?0.236, ?0.254; P＜0.05) of NRL, SRL, DRL; positively correlated with FAZ and BCVA (r=0.221, 0.183; P＜0.05). BCVA was negatively correlated with VD (r=?0.210, ?0.190, ?0.245) and SD (r=?0.239, ?0.207, ?0.296) of NRL, SRL, and DRL (P＜0.05), but not correlated with FAZ (r=0.099, P＞0.05).ConclusionThe decrease of macular perfusion and the morphological change of FAZ accompanied by HbA1c increased.
Objective To observe and analysis the features of images of fundus fluorescein angriography (FFA) in low-perfused retinopathy caused by cephalo-cervical peripheral vascular stenosis or occlusion. Methods The results of FFA of 27 patients diagnosed with carotid artery stenosis or occlusion by digital subtraction angiography (DSA) and examination of Doppler and vascular-pulsation were retrospectively analyzed. Result All of the patients had a delayed arm-retinal circulation duration from 20.0 to 81.08 seconds with the mean of 32.1 seconds; a delayed retinal arteriovenous filling duration from 6 to 64.0 seconds with the mean of 24.2 seconds. Delayed arm-retinal circulation duration and retinal a rteriovenous filling duration in 10 cases (37.0%); microangioma, vascular wall staining, nonperfused capillary area in 11 (40.7%); and anterior ischemic syndrome in 6 (22.2%) were found. In the 6 patients with anterior ischemic syndrome, 4 cases had narrow retinal artery, segmental changes of blood stream, vascular atresia, and abnormal arterio-venous anastomosis, and 2 cases had bold vascular loops. Conclusions The main manifestations of FFA in patients with low-perfused retinopathy are malperfusion and retinal ischemia, whose degrees relate to the extend of carotid artery stenosis or atresia, and the process of the disease.Serious retinal ischemia may combined with anterior ischemic syndrome. (Chin J Ocul Fundus Dis，2004，20：84-86)
In order to observe the effect of far infrared rays on the survival of skin flap, the following experiment was performed. Forty-eight SD rats were selected and divided into two groups. The rats received 0.3 w/cm2 radiation twice a day from 3 days before operation to 5 days after operation in the experimental group, while in the control group the rats received none before or after the operation. The flap was designed as 2 cm x 6 cm in the back of the rats with the pedicle caudalward. The microcirculatory changes of the flap were observed, and the survival area of the flap was calculated. The results showed that either in the proximal or in the distal part of the graft, in the experimental group, the mean opening rate, diameter and the flowing velocity of the microvessels were significantly higher than those in the control group (P lt; 0. 05). The mean rate of survival area of the experimental group (80.5%) was also higher than that of the control group (62.7%) (P lt; 0.01). It was suggested that radiation with far infrared rays could dilate the microvessels, improve the flap microcirculation, therefore, enhance the survival of the randomized skin flap.