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Aiming at the problem that the small samples of critical disease in clinic may lead to prognostic models with poor performance of overfitting, large prediction error and instability, the long short-term memory transferring algorithm (transLSTM) was proposed. Based on the idea of transfer learning, the algorithm leverages the correlation between diseases to transfer information of different disease prognostic models, constructs the effictive model of target disease of small samples with the aid of large data of related diseases, hence improves the prediction performance and reduces the requirement for target training sample quantity. The transLSTM algorithm firstly uses the related disease samples to pretrain partial model parameters, and then further adjusts the whole network with the target training samples. The testing results on MIMIC-Ⅲ database showed that compared with traditional LSTM classification algorithm, the transLSTM algorithm had 0.02-0.07 higher AUROC and 0.05-0.14 larger AUPRC, while its number of training iterations was only 39%-64% of the traditional algorithm. The results of application on sepsis revealed that the transLSTM model of only 100 training samples had comparable mortality prediction performance to the traditional model of 250 training samples. In small sample situations, the transLSTM algorithm has significant advantages with higher prediciton accuracy and faster training speed. It realizes the application of transfer learning in the prognostic model of critical disease with small samples.
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Objective To investigate the effect of polylactic-co-glycolic acid (PLGA)/graphene oxide (GO) nanofibers combined with brain derived neurotrophic factor (BDNF) on neural stem cells (NSCs) proliferation and differentiation as well as on the spinal cord injury repair.Methods PLGA/GO nanofibers were manufactured and absorbed with BDNF,and the microstructure of PLGA/GO nanofibers was observed by scanning electron microscope.The loading efficiency and release curve of BDNF on PLGA/GO nanofibers were measured by ELISA.NSCs were implanted on the surface of PLGA/GO and PLGA/GO/BDNF nanofibers.The absorbance values of each group were measured by MTT method,and the expression of Tuj-1 was observed by immunofluorescence and PCR.A total of 30 female SD rats were divided into control group (n =10),PLGA/GO group (n =10) and PLGA/GO/BDNF group (n =10) according to random number table.T9 spinal cord tissue was cut by Venus scissors to establish spinal cord hemisection injury model of rats.PLGA/GO and PLGA/GO/BDNF nanofibers were implanted onto the surface of injury site.BBB score was used to assess the motion functional recovery of the rats at 1,7,14 and 28 days after operation.Immunofluorescence staining of neuron specific nucleoprotein (NeuN)and glial fibrillary acidic protein (GFAP) were performed to observe the expressions of neurons and astrocytes at the injured site respectively one month after injury.Results The PLGA/GO nanofibers showed an irregular smooth fiber-like structure,and the average fiber diameter was (987.5 ± 176.3)nm.NSCs could differentiate into neurons on the nanofibers.The result of ELISA showed loading rate of BDNF on PLGA/GO nanofibers was about 47.5％.The release curve showed that BDNF was first released about 30％ on the first day and then about 60％ on the 21st day.The results of MTT and PCR showed that optical density value and Tuj-1 gene expression in the PLGA/GO/BDNF group were significantly higher than those in the PLGA/GO group (P ＜ 0.05).The animal experiment results showed that the BBB score of PLGA/GO/BDNF group was (15.3 ±0.7) points at 28 days after injury,which was significantly higher than that of the injury control group [(11.8 ± 0.8) points] and that of PLGA/GO group [(12.7 ±0.8) points] (P ＜ 0.05).Immunofluorescence results showed that the expression of NeuN in PLGA/GO/BDNF group was 13.7 ± 2.2,significantly higher than that in injury control group (4.3 ± 2.9) (P ＜0.05),and the expression of GFAP in PLGA/GO group was (25.6 ± 4.3) ％ significantly lower than that in injury control group [(38.5 ± 6.2) ％] and PLGA/GO group [(36.7 ± 7.3) ％] (P ＜ 0.05).Conclusion PLGMGO nanofibers combined with BDNF can effectively promote the proliferation and neuron differentiation of NSCs in vitro and repair spinal cord injury in vivo through orthotopic transplantation at the injury site.
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To study the change of the dominant eye in the age-related cataract patients before and after surgery, to analyze the correlation between the orientation of the dominant eye and the visual quality, and to observe whether the patients with the change in dominant eye were converted to dizziness. Methods: A total of 44 patients, with age-related cataract between 60 and 80 years old were enrolled. Group A: the non-dominant (secondary) eye served as the surgical eye (n=35); Group B: the dominant eye served as the surgical eye (n=9); Group C: the operation was performed on the contralateral eye after a month (n=28). Measurement of the dominant eye was performed before operation, 1 week after operation and 1 month after the operation. The changes in the uncorrected distance visual acuity (UCDVA), contrast sensitivity (CS), best corrected visual acuity (BCVA) and spherical equivalent (SE) between the dominant and non-dominant eye were compared. Results: The UCDVA, CS, BCVA and SE were significantly improved at 1 day after the operation. There was significant difference between the 2 groups (P0.05); in group B, the UCDVA, CS, BCVA in the dominant eye were better than the non-dominant eye's, but the difference was not statistically significant (P>0.05). After operation: the UCDVA, CS and BCVA in the dominant eye in group A and group B were higher than those of the non-dominant eye with statistical difference (P0.05). The dominant eye's transformation occurred in group A when the non-dominant eye's postoperative visual quality improved over the leading eye. The transformation rate was 60% in 1 week, and the conversion rate was 80% in 1 month. In group C, the dominant eye reduction rate was 100%, and the visual quality was not significant difference between the two eyes (P>0.05). After the operation, the patients with the dominant eye's transformation felt discomfort, which could be relieved within 1 week. Conclusion: The location of the dominant eye was correlated with uncorrected visual acuity, contrast sensitivity, and the best corrected visual acuity. The dominant eye's transformation occurred when the non-dominant eye's postoperative visual quality improved over the leading eye after the surgery. If the contralateral eye's surgery was performed in a short term, the dominant eye can be returned to the initial state.
Subject(s)
Aged , Aged, 80 and over , Humans , Middle Aged , Cataract , Therapeutics , Cataract Extraction , Phacoemulsification , Treatment Outcome , Visual AcuityABSTRACT
BACKGROUND:At present, spinal cord ischemia/reperfusion injury is considered as the main reason for secondary paralysis after spinal decompression, and to control the levels of stress-related proteins and excitatory amino acids plays an important role in the treatment of spinal cord ischemia/reperfusion injury. OBJECTIVE:To investigate the expression level of protein disulfide-isomerase A3 (PDIA3) after spinal cord ischemia/reperfusion injury in rabbits. METHODS:Thirty-six New Zealand white rabbits were enrolled, the models of spinal cord ischemia/reperfusion injury were established using Zivin's method, and were then randomized into six groups (n=6 per group). The rabbit abdominal aorta in control group was exposed without vascular occlusion and then the abdominal cavity was closed 30 minutes later. In experimental groups, the abdominal aorta was blocked for 30 minutes, followed by 0, 6, 12, 24 and 48 hours of reperfusion, and then the abdominal cavity was closed. The neurological function was evaluated with a modified Tarlov score. The L3-5lumbar vertebrae were removed, and PDIA3 was screened by two-dimensional fluorescence differential gel electrophoresis combined with mass spectrometry, and then its temporal and spatial changes in the spinal cord were detected by western blot assay and immunohistochemistry. RESULTS AND CONCLUSION:The function of hind limbs was improved in all the experimental groups after spinal cord ischemia/reperfusion injury, and the modified Tarlov scores reached the peak at 24 hours after schemia/reperfusion injury, and decreased slightly at 48 hours. The expression of PDIA3 in the control group showed clear imprinting, which was slightly strengthened at 0 hour, became more strengthened at 6-12 hours, significantly reduced to the minimum level at 24 hours, and returned to the level of 6-12 hours at 48 hours after ischemia/reperfusion. Immunohistochemical results showed that there was visible PDIA3 in the cytoplasm of neurons, and the expression level in the interneurons was significantly higher than that in the motor neurons. These results suggest that upregulated PDIA3 appears in the development and progression of spinal cord ischemia/reperfusion injury, indicating that PDIA3 is closely related to spinal cord ischemia/reperfusion injury, which can be used as a new diagnosis and treatment target.