The current quantitative methods of bilirubin have disadvantages such as high cost and low sensitivity. Due to the negative correlation between the level of serum bilirubin and the risk of cardiovascular diseases, a fluorescent ratiometric film sensor was developed aiming at bilirubin detection at low level concentration. Blue-emitting and red-emitting gold nanoclusters were assembled into the same film using layer-by-layer self-assembly technology. Detection of bilirubin was achieved based on the intensity ratio of the two nanoclusters. Bilirubin exposure causes fluorescent quenching of the film. The fluorescence intensity ratio of the two cluster probes had quantitative relationship versus bilirubin concentration. Based on this film sensor, a portable fluorescence detection system was designed for the ratiometric sensing of bilirubin. The hardware of the system was mainly composed of main control chip STM32F407, TSL237 and TSL238T optical frequency sensor. A light-avoiding dark room and detection light path were designed through three-dimensional printing to reduce the interference from ambient light and improve detection accuracy. Experimental results showed that the proposed detection system had strong anti-interference, good stability and accuracy. The linear coefficient of bilirubin detected by this system was 0.987. The system presented good results in reproducible experiments and possessed a good linear relationship with the data obtained by standard spectrofluorometer. The portable system is expected to detect serum bilirubin at low levels.
Objective To investigate the effect of chondroitinase ABC (ChABC) on the expression of growth associated protein 43 (GAP-43) and gl ial fibrillary acidic protein (GFAP) after spinal cord injury (SCI) in rats. Methods A total of 150 adult female SD rats, weighing 250-300 g, were randomly divided into ChABC treatment group (group A), sal ine treatment group (group B), and sham operation group (group C) with 50 rats in each group. In groups A and B, the rats were made the SCI models and were treated by subarachnoid injection of ChABC and sal ine; in group C, the rats were not treated as a control. At 1, 3, 7, 14, and 21 days after operation, the Basso, Beattie, and Bresnahan (BBB) score system was used toevaluate the motion function, and immunofluorescent histochemical staining was used to observe the expressions of GAP-43 and GFAP. Results At different time points, the BBB scores of groups A and B were significantly lower than those of group C (P lt; 0.05); there was no significant difference in BBB score between groups A and B after 1, 3, and 7 days of operation (P gt; 0.05), but the BBB score of group A was significantly higher than that of group B after 14 and 21 days of operation (P lt; 0.01). At different time points, the GAP-43 and GFAP positive neurons of groups A and B were significantly higher than those of group C (P lt; 0.05). After 14 and 21 days of operation, the GAP-43 positive neurons of group A were more than those of group B (P lt; 0.01). After 7, 14, and 21 days of operation, the GFAP positive neurons of group A were significantly less than those of group B (P lt; 0.01). Conclusion ChABC can degrade gl ial scar, improve the microenvironment of the injured region and enhance the expression of GAP-43, which promotes axonal growth and extension.
ObjectiveTo observe the effect of transplantation of neural stem cells (NSCs) induced by all-trans-retinoic acid (ATRA) combined with glial cell line derived neurotrophic factor (GDNF) and chondroitinase ABC (ChABC) on the neurological functional recovery of injured spinal cord in Sprague Dawley (SD) rats. MethodsSixty adult SD female rats, weighing 200-250 g, were randomly divided into 5 groups (n=12): sham operation group (group A), SCI model group (group B), NSCs+GDNF treatment group (group C), NSCs+ChABC treatment group (group D), and NSCs+GDNF+ChABC treatment group (group E). T10 segmental transversal injury model of the spinal cord was established except group A. NSCs induced by ATRA and marked with BrdU were injected into the site of injury at 8 days after operation in groups C-E. Groups C-E were treated with GDNF, ChABC, and GDNF+ChABC respectively at 8-14 days after operation;and group A and B were treated with the same amount of saline solution. Basso Beattie Bresnahan (BBB) score and somatosensory evoked potentials (SEP) test were used to study the functional improvement at 1 day before remodeling, 7 days after remodeling, and at 1, 2, 5, and 8 weeks after transplantation. Immunofluorescence staining and HE staining were performed to observe the cells survival and differentiation in the spinal cord. ResultsFive mouse died but another rats were added. At each time point after modeling, BBB score of groups B, C, D, and E was significantly lower than that of group A, and SEP latent period was significantly longer than that of group A (P<0.05), but no difference was found among groups B, C, D, and E at 7 days after remodeling and 1 week after transplantation (P>0.05). BBB score of groups C, D, and E was significantly higher than that of group B, and SEP latent period was significantly shorter than that of group B at 2, 5, and 8 weeks after transplantation (P<0.05);group E had higher BBB score and shorter SEP latent period than groups C and D at 5 and 8 weeks, showing significant difference (P<0.05). HE staining showed that there was a clear boundary between gray and white matter of spinal cord and regular arrangement of cells in group A;there were incomplete vascular morphology, irregular arrangement of cells, scar, and cysts in group B;there were obvious cell hyperplasia and smaller cysts in groups C, D, and E. BrdU positive cells were not observed in groups A and B, but could be found in groups C, D and E. Group E had more positive cells than groups C and D, and difference was significant (P<0.05). The number of glial fibrillary acidic protein positive cells of groups C, D, and E was significantly less than that of groups A and B, and it was significantly less in group E than groups C and D (P<0.05). The number of microtubule-associated protein 2 positive cells of groups C, D, and E was significantly more than that of groups A and B, and it was significantly more in group E than groups C and D (P<0.05). ConclusionThe NSCs transplantation combined with GDNF and ChABC could significantly promote the functional recovery of spinal cord injury, suggesting that GDNF and ChABC have a synergistic effect in the treatment of spinal cord injury.
Objective To investigate the delay of the denervated skeletal muscle atrophy with the method of restraining the increment of the connective tissues by tetrandrine and hormone. Methods The left hind limbs of 42 male adult SD rats were made into models of the denervated gastrocnemius, and then the rats were randomly divided into 3 groups, with 14 rats in each. In Group A, tetrandrine (8 mg/L）was injected into the denervated gastrocnemius; in Group B, triamcinolone acetonide（1.6 g/L） was injected; in Group C (the control group),normal saline was injected. Enough samples were obtained according to the different observation indexes at 30 days after operation. Electromyography, muscle wet weight measurement, light microscopy,electron microscopy,and microimage analysis were performed. ResultsThe fibrillation potential amplitude was 0.195 8±0.041 9 μV in Group A and 0.185 2±0.050 3 μV in Group B, and there was no significant difference betweenthe two groups (Pgt;0.05). However,in Group C the fibrillation potential amplitude was 0.137 7±0.058 9μV. The fibrillation potential amplitude was significantly greater in Group A than in Group C（Plt;0.05）. The muscle wet weight was 1.740 0±0.415 9 g in Group A and 1.940 1±0.389 4 gin Group B, and there was no significant difference between the two groups(Pgt;0.05).However, in Group C the muscle wet weight was 0.800 0±0.100 0 g. The muscle wet weight was significantly greater in Group A than in Group C（Plt;0.05）.The microscopy showed that more remarkable atrophy occurred in the control group. The muscle fibers were more complete, thicker and larger, with more nuclei and clearer cross-lines. More connective tissue and flat cells could be observed in Groups A and B. The myogenic protein amount was 440.124 2±46.135 6 in Group A and 476.211 4±41.668 8in Group B, and there was no significant difference between the two groups(Pgt;0.05).However, in Group C the amount was 380.040 0±86.315 9.The myogenic protein amount was significantly greater in Group A thanin Group C（Plt;0.05）. The muscle fiber number, diameter, cross section, and connective tissue increment were all significantly greater in Group A than in Group C（Plt;0.05）; however, there wasno significant difference between Groups A and B (Pgt;0.05). The electron microscopy showed that there were more degeneration changes, such as muscle silk disorder, chondriosome disappearance, and hepatin reduction, could be observed inGroup C than in Groups A and B. Conclusion Tetrandrine and hormone can delay the denervated skeletal muscle atrophy by restraining the increment of the connective tissues.
ObjectiveTo evaluate the dynamic changes of blood flow and blood pressure of acute hindlimb ischemia of rats by laser Doppler flowmetry (LDF) and laser Doppler perfusion imaging (LDPI). MethodsThe acute hindlimb ischemia model of rats was established by resection of rats femoral arteries of left hindlimb. The blood flow and blood pressure between operated and nonoperated hindlimbs were examined by LDF on 2, 7, 14, 28, and 49 d after operation. And the blood flow was evaluated by LDPI on 7 d after operation. ResultsAll rats survived after operation and no hindlimb necrosis occurred. The mean score was 2 on 14 d after operation and 1 on 49 d after operation. The ratio of blood flow between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 1.31±0.439 (P=0.021). The ratio of blood flow on 7 d (0.82±0.538) and 14 d (0.93±0.294) after operation was significantly lower than that on 2 d after operation (P=0.032 and P=0.019), although the difference between the two former was not significant (P=0.502). Furthermore, the ratio of blood flow on 28 d after operation reached the bottom (0.41±1.970), which was obviously lower than that on 2, 7, and 14 d after operation (P=0.004, P=0.007, and P=0.006). The blood flow of operated hindlimbs recovered approximately the value before operation (0.98±0.093), which was significantly lower than that on 2 d (P=0.010), higher than that on 28 d (P=0.005), but not different from that on 7 d and 14 d after operation (P=0.126 and P=0.382). The ratio of blood pressure between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 0.47±0.375 (P=0.031). The ratio of blood pressure decreased on 7 d after operation (0.44±0.118), which was not different from that on 2 d after operation (P=0.203). Furthermore, the ratio of blood pressure on 14 d after operation reached the bottom (0.35±0.115), which was obviously lower than that on 2 d and 7 d after operation (P=0.001 and P=0.036). On 28 d after operation, the ratio of blood pressure increased (0.54±0.146), which was significantly higher than that on 14 d after operation (P=0.008), while not different from that on 2 d (P=0.493) and 7 d after operation (P=0.551). The ratio of blood pressure recovered approximately the value before operation (0.97±0.094), which was significantly higher than that on 2, 7, 14, and 28 d (P=0.013, P=0.021, P=0.002, and P=0.031). ConclusionAcute hindlimb ischemia model of rats can be established by resection of rats femoral arteries of left hindlimb and the most serious stage of hindlimb ischemia is on 14-28 d after operation. LDF and LDPI are of importance for monitoring the dynamic changes of rats hindlimb ischemia after operation.
Objective To establish a reliable rats model of orthotopic liver transplantation with non-heart beating donors. Methods The model was established with modified double-cuff method. According to obtain pre-liver warm ischemia time experiencing non-heart-beat the rats were divided into 3 groups: 10 min (R10 group), 20 min (R20 group) and 30 min (R30 group), then one week survival after operation was compared in rats. Results The operative time of donor was 30 min approximately except warm ischemia time and the cold preservation time of donor liver was 1 h. The anastomotic time for suprahepatic vena cava was 12-22 min (mean 15 min). The anastomotic time for portal vein and infrahepatic vena cava was about 2 min and 1 min, respectively. The anhepatic phase sustained 14-24 min (mean 19 min). The operative time of receptor was 50-65 min (mean 60 min). Twelve rats died at 24 h after operation, which was considered as operative failure. The success rates of operation in R10 group, R20 group, and R30 group were 95% (19/20), 80% (16/20), and 65% (13/20), respectively. After one week the survival rate was 95% (18/19), 81% (13/16), and 54% (7/13), respectively. Conclusions Improved non-heart donor liver transplantation model of rat on the basis of Kamada’s “twocuff technique” acts as a good simulation in clinical non-heart-donor liver transplantation. This study showes that rat liver can tolerate warm ischemia time less than 30 min, the short-term survival after transplantation can reach satisfactory results. However, long-term survival requires further study.
Objective To investigate the quantity and distribution of motor fiber of rat’s C7 nerve root. Methods Motor fiber quantity and section area in the main nerves of the upper extremity and the fascicles of C7 in 30 SD rats were analyzed.Results Fascicles and certain amount (207) of motor fibers from the anterior division of C7 were distributed to musculocutaneous nerve and median nerve, the orientation of these fibers were not clear. The ones (323) from posterior division were to the axillary, radial, and dorsal thoracic nerves, thus the orientation of these fascicles was relatively definite. Conclusion Thedistribution of the motor fibers and fascicles in the divisions of C7 in rat is similar to human beings, so rat is a relatively good model for the study of selective C7 nerve root transfer.
Objective To investigate the effect of the vascular endothelial growth factor (VEGF) gene therapy, the surgical delay, and the combination of the two therapeutic approaches on the survival of the rat over-area abdominal axial skin flap. Methods In 48 male Wistar rats (weight, 400-450 g), a model of the abdominal axial skin flap supplied by the superficial epigastric blood vessel was created. The rats were randomly divided into 6 groups: Group A (the blank group), Group B (the gene-therapy-during-operation group), Group C (the gene-therapy-before-operation group), Group D (themerely-surgical-delay group), Group E (the gene-therapy-during-surgical-delay group), and Group F (the gene-therapy-aftersurgical-delay group). Seven days after operation, the survival rate of the skin flap was measured; the specimens were harvested from the skin flap for a histological investigation of themicrovessels and for an immunohistochemical staining to observe the expression of VEGF165. Results The average survival rate of the skinflap was significantly greater in each of the treated groups than in Group A (Plt;0.05); the rate was the greater in Group E (Plt;0.05), but with no statistically significant difference between the other treated groups (Pgt;0.05). The average number of the microvessels was significantly greater in Groups B, C, E andF than in Groups A and D (Plt;0.05), but with no statistically significant difference between Groups B, C, E and F and between Groups A and D (Pgt;0.05). The lumen diameter of the microvessels was significantly greater in Group D than in Groups E and F (Plt;0.05), and the diameter was significantly greater in Groups D, E andF than in the other groups (Plt;0.05). More deposition of VEGF DNA detected by the immunohistochemical staining was in Groups B, C, E and F than in Groups A and D. There was no newly-formed blood vessel in the rat cornea in the treated groups.Conclusion Both the administration of pcDNA4-VEGF165 and the surgical delay can improve the survival of the rat abdominal axial skin flap, but the mechanism of the effect is different in explanation. The combination of the two therapeutic approaches can achieve a better effect.
Objective To explore the effects of several immunosuppressants on the cell numbers of cultured rat macrophages and Schwann’s cells. Methods The macrophages and Schwann’s cells were cultured from the newborn Wistar rats. Different concentrations of methylprednisolone(10-3, 10－4,10－6 and 10－8 mol/L), CsA(10－5, 10－6, 10－7 and 10－8 mol/L) and FK506(10-6, 10－7, 10－8 and 10－9 mol/L) were administrated to the cells, while control group was given no drugs. Twentyfour, 48 and 72 hours after administration, the cells from different concentrations were measured with MTT methods respectively. Theresults were compared and analyzed statistically. Results Only high concentration methylprednisolone (10-4 mol/L) and a certain range of concentrations of CsA (10-6，10-7 and 10-8 mol/L) and FK506 (10-7,10-8 and 10-9 mol/L) can provide protection to culturedrat macrophages. Under most concentrations, CsA and FK506 had no effects onthe cell number of cultured rat Schwann’s cell. Only with high concentration CsA (10-5 mol/L) and methylprednisolone (10-3 mol/L) could significantly decreased the cell number of Schwann’s cell. Long time (72 hours) and low dosage (10-8 mol/L) administration of methylprednisolone could significantlyprotect Schwann’s cell. Conclusion High concentration methylprednisolone and some certain concentration CsA and FK506 can protect cultured rat macrophages. But high concentration CsA and methylprednisolone prohibit the proliferation of Schwann’s cells. Only long time and low dosage methylprednisolonecan protect cultured rat Schwann’s cells.
【Abstract】ObjectiveTo compare the effects of self-designed KYL solution on rat liver preservation with UW solution. Methods Using non-circulated isolated perfused rat liver,SD rat livers were randomly preserved for 0、4、8、16、24 and 48 hours with self-designed KYL solution or UW solution. The effects were assessed by measuring the bile production, the contents of AST， ALT，LDH，free radical（ MDA） and SOD in KrebsHenseleit’s perfusate and the content of intracellar calaium of the rat hepatocytes, and by observing the morphological changes in liver. At the same time, the normal saline was used to preserve the rats liver as negative comparison to know if KYL solution and UW solution can prevent the ischemiareperfusion injury in rat liver transplantation.Results At different periods within 16 hours of preservation,the bile production of the rat livers which were preserved by KYL solution were more than those were preserved by UW solution （P＜0.01）, JP2The contents of AST， ALT and LDH in Krebs-Henseleit’s perfusate were near in UW solution’s. The content of intracellar calaium of the rat hepatocytes which were preserved by KYL solution were less than those were preserved by UW solution （P＜0.01）. In KYL group, the content of MDA was lower than that UW group, the content of SOD was higher than that UW group at 24 and 48 h(P＜0.01). Morphological changes in both groups were almost same. All variables of both groups were better than the rat livers preserved by the normal saline. It was proved that both KYL solution and UW solution could protect the rat livers. Conclusion The study indicated that the effects of self-designed KYL solution on rat liver preservation are similar to that of UW solution. The bile production after reperfusion and the content of intracellar calaium of the rat hepatocytes in KYL group are better than those in UW group .The effect of prevention of rat hepatocellular oedema by self-designed KYL solution are worse than that of UW solution.