Objective To explore the proper dosage of establishment of stable hepatic oval cells （HOC） prolif-eration model by using 2-acetaminofluorene （2-AAF） combined with two-third partial hepatectomy （2/3 PH） surgery， and to explore isolated and cultured method of HOC in vitro. Methods The 174 Wistar rats were randomly divided into 4 experimental groups （each group enrolled 30 rats）， saline group （n=30）， and untreated group （n=24）. Rats of 4 experi-mental groups were underwent gavage of 5， 10， 15， and 20 mg/（kg ? d） 2-AAF， corresponding to the groups from No.1 to No.4 group. Rats of saline group received saline gavage and rats of untreated group didn’t received any treatment. A standard 2/3 PH surgery was performed on the 5th day after gavage， then the same gavage method was still administrated as preoperation untill rats were sacrificed. The liver tissues of 6 selected rats were adopted and identified by HE staining and immunohistochemical staining on 4， 8， 12， and 16 days after PH for observation of the proliferation of HOC in every group， on 4 days， levels of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） were tested in addition. HOC were isolated and purified by collagenase perfusion method and percoll gradient centrifugation. Results The surv-ival rates of untreated group，saline group，No.1 group，No.2 group，No.3 group，and No.4 group were 100% （24/24），93% （28/30），93% （28/30），90% （27/30），90% （27/30），and 80% （24/30） respectively. Compared with the saline group and untreated group， the levels of serum ALT and AST increased significantly in No.2， No.3， and No.4 group on the 4th day after PH （P＜0.05）. The results of HE staining showed that No.2， No.3， and No.4 group were observed visibly different level of damage at liver tissue， and the proliferation level of HOC were most obviously in No.3 and No.4 group. The results of immunohistochemical staining revealed that proliferation cells were positively expressed oval cell marker-6 （OV-6）. The number of OV-6 positive cells were increased significantly with the increase of dosage of 2-AAF between 4 days and 12 days after operation， and proliferation levels were related with dosages of 2-AAF （P＜0.05）. In all cultured cells， 80% of cells were OV-6 positive cells after isolation and culture by using collagenase perfusion method and percoll gradient centrifugation. Conclusions The methods of gavage of 2-AAF at 15 mg/（kg ? d） combined with 2/3 PH surgery can establish the HOC proliferation model on the 12th day， as well as the rats have lower mortality and better tolerance， especially. The collagenase perfusion method and percoll gradient centrifugation can be used to isolate HOC effectively.
Objective To explore the key technique of allogeneic whole pancreaticoduodenal transplantation (WPDT) in rats. MethodsWPDT model was established between Lewis rats as donors and Wistar rats (with type 1 diabetes mellitus) as recipients. End to side anastomosis was performed in abdominal aorta of donors and recipients. The portal vein of the graft was anastomosed with the recipients left renal vein by cuff technique. And side to side anastomosis was made between the graft duodenum and the host jejunum. ResultsForty-four of 50 rats were successfully performed WPDT. Amongthem, 8 rats died in postoperative 3 days, the survival time of residual 36 rats was 6-16 days, with an average of (10.45±3.30) days. The peak of death appeared on day 7-10 after operation. The typical acute rejection in pathological changes were observed on day 7. ConclusionSkilled microsurgical techniques and emphasis on details are important to establish WPDT model.
Objective To investigate the expression of T cell receptor (TCR) Vβ8.3 gene on CD4+ T lymphocytes in the rats with experimental autoimmune uveoretinitis (EAU). Methods Eighteen Lewis rats were divided into EAU, complete Freund′s adjuvant, and the control group. Inter photoreceptor retinoid-binding protein (IRBP) R16 peptide was synthesized using Fmoc procedure for induction of EAU. Magnetic absorption cell sorting (MACS) me thod was used to isolate the CD4+T lymphocytes from the spleen of the rats. Flow cytometry was used to monitor the efficiency of isolation. The expression of TCR Vβ8.3 gene segment on CD4+T lymphocytes was determined by fluorescent quantitative polymerase chain reaction. Results EAU was successfully induced in the Lewis rats immunized with IRBP R16 peptide. The proportion of CD4+T lymphocytes isolated by means of MACS was statistically higher than that before isolation (P＜0.001). The expression of TCR Vβ8.3 gene segment on CD4+ T lymphocytes in EAU rats was significantly higher than that in the control (P＜0.05). Conclusions There is a predominant usage of antigen-specific TCR Vβ 8.3 gene in EAU rats induced by IR BP R16 peptide, which may serve as a target for immunotherapy of EAU. (Chin J Ocul Fundus Dis，2004，20：165-167)
A acute partial obstructive hepatocholangitis model by selective ligation and injection of E coli into left hepatic bile duct was successfully founded in rat. Using parameters including mortality, mitochondrial glutamic oxalacetic transaminase and ornithine carbamoytransferase activity, pathological observation and blood culture of bacteria, we evaluated the model. The authors emphasize that this models is superior to the wole-bile-duct-challenged cholangitis model, which is characterized by liver injury.
Recent studies have introduced attention models for medical visual question answering (MVQA). In medical research, not only is the modeling of “visual attention” crucial, but the modeling of “question attention” is equally significant. To facilitate bidirectional reasoning in the attention processes involving medical images and questions, a new MVQA architecture, named MCAN, has been proposed. This architecture incorporated a cross-modal co-attention network, FCAF, which identifies key words in questions and principal parts in images. Through a meta-learning channel attention module (MLCA), weights were adaptively assigned to each word and region, reflecting the model’s focus on specific words and regions during reasoning. Additionally, this study specially designed and developed a medical domain-specific word embedding model, Med-GloVe, to further enhance the model’s accuracy and practical value. Experimental results indicated that MCAN proposed in this study improved the accuracy by 7.7% on free-form questions in the Path-VQA dataset, and by 4.4% on closed-form questions in the VQA-RAD dataset, which effectively improves the accuracy of the medical vision question answer.
Purpose To investigate whether experimental autoimmune uveitis can be induced equally in different rats by urea soluble fraction of bovine melanin-associated antigen(USF-BMAA),and,if so,difference among them. Methods Lewis rats,F344 rats,Wistar rats were immunized with USF-BMAA emulsified with complete Freud is adijuvant and Bordelella pertussis to induce experimental autoimmune uveitis.The animal models were investigated clinically and histopathologically and compared with each other. Rusults Experimental autoimmune uveitis could be induced in Lewis rats,F344 rats and Wistar rats with US-BMAA.Clinical and histopathalogical examination showed that bilateral ocular inflammation developed after immunization 9-13 days.Although inflammation was mainly located in anterior uvea,a mild focal choroiditis was noted in those with severe anterior inflammation.No inflammation was observed in the retina and pineal gland.Experimental autoimmune uveieis induced with USF-BMAA was similar to experimental autoimmune anterior uveitis incited with BMAA presented by other authors.Inflammation induced with USF-BMAA in F344 rats and in Lewis rats was quite similar in the severity and course of the model.But the inflammation was less in Wistar rats compared with that in Lewis rats and F344 rats. Conclusion Experimental autoimmune anterior uveitis was successfully induced with USF-BMAA in Lewis rats,F344 rats and Wistar rats.The difference with regard to the severity among these aminals were propably attributed to their genetic bankground. (Chin J Ocul Fundus Dis,1998,14:149-152)
ObjectiveTo investigate the establishment of a risk nomogram model for predicting vagus excitatory response in patients with functional epilepsy after radiofrequency thermocoagulation.MethodsA total of 106 patients with epilepsy admitted to the neurosurgery department of our hospital from January 2016 to June 2020 were selected and divided into the Vagus excitatory response (VER) group and the non-VER group according to their occurrence or absence. Logistic regression analysis was used to screen out the risk factors of VER during SEEG-guided Percutaneous radiofrequency thermocoagulation (PRFT) in patients with functional epilepsy, and R software was used to establish a histogram model affecting VER in SEEG-guided PRFT. Bootstrap method was used for internal verification. C-index, correction curve and ROC curve were used to evaluate the prediction ability of the model.ResultsLogistic regression analysis showed that age [OR=0.235, 95%CI (0.564, 3.076)], preoperative fugl-meyer score [OR=4.356, 95%CI (1.537, 6.621)], depression [OR=0.995, 95%CI (1.068, 7.404)], and lesion range [OR=1.512, 95%CI (0.073, 3.453)] were independent risk factors for the occurrence of VER in PRFT under the guidance of SEEG (P<0.05), and were highly correlated with the occurrence of VER in PRFT. Based on the above six indicators, a SEEG-guided colograph model of VER risk in PRFT was established, and the model was validated internally. The results showed that the C-index of the modeling set and validation set were 0.779 [95%CI (0.689, 0.869)] and 0.782 [95%CI (0.692, 0.872)], respectively. The calibration curves of the two groups fit well with the standard curves. The areas under the ROC curve (AUC) of the two groups were 0.779 and 0.782 respectively, which proved that the model had good prediction accuracy.ConclusionFor patients with functional epilepsy requiring seeg-guided PRFT therapy, age, preoperative Fugl-meyer score, depression and lesion range should be taken into full consideration to comprehensively assess the incidence of VER, and early intervention measures should be taken to reduce and reduce the incidence, which has good clinical application value.