Objective To investigate the spatial and temporal regulation effect of VEGF on human fetal retinal vascularization and angiogenesis. Methods The posterior segmental retinas from 54 human fetuses of the 9th week to the 40th week were studied by immunohistodhemistry standing for the expressions of VEGF and PCNA. Results 1. The distribution of VEGF espression was spiking and the peaks were during the 9th-13th and around the 26th week. 2. PCNA immunoreactivity was localized in spindle cells and vascular endothelial cells. The expression level was fluctuated during the developmental process. The peaks were during the 9th-13th and around the 21st week. In these periods, the spindle cells kept proliferating and differentiating, and remodelled subsequently to form the inner side retinal vessels. From the 26th or 34th week, the PCNA immununoreactivity is fully expressed in the vascular endothelial cells of the inner and outer margin of inner nuclear layer(INL) and kept to full terms. 3. Significant positive correlation were shown between the content of VEGF in the retina and that of PCNA in spindle cells and vascular endothelial cells(r=0.736,p＜0.01). Conclusion VEGF was positively involved in modulating human fetal retinal vascularization and angiogenesis. (Chin J Ocul Fundus Dis,1999,15:12-15)
Objective To investigate the effect of methylprednisolone on the expression of glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) in Müller cells of rats’ retinae injured by laser. Methods Forty SD rats were randomly divided into two groups and inflicted with laser photocoagulation.The rats in treatment group were given methylprednisolone by intraperitoneal injection with a dose of 30 mg/kg for 3 days.At the 3rd,7th,14th,and 28th day after photocoagulation respectively, the eyes were enucleated,fixed and cut into sections.Immunohistochemical examination was used to detect the expression of PCNA and GFAP. Results After photocoagulation the Müller cells expressed PCNA both in the treatment and control group,and the expression of PCNA decreased sharply after 3 days. The expression of PCNA in treatment group was less than that in control group. After photocoagulation the Müller cells also expressed GFAP and the expression of GFAP lasted for at least 28 days ,and the expression of GFAP expression in the treatment group was less than that in the control group. Conclusion Methylprednisolone can reduce the expression of GFAP and PCNA in Müller cells of rats’ retinae injured by laser. (Chin J Ocul Fundus Dis, 2002, 18: 299-301)
To determine the state of fibroblast during the process of development of hypertrophic scar (HS), 40 specimens of HS in different periods were collected. The expressions of prolifrating cell nuclear antigen (PCNA) and Ag-protein in nucleolar organizer regions (Ag NORs) as well as the content of total amino acids in the tissues were examined. The hypertrophic scar of 1st and 3rd month old, the expression of PCND and Ag NORs were the highest. In the 9th and 12th month old, althrough PCNA was nearly negative, but the expression of Ag NORs was low. The content of total amino acid was increased gradually as HS developed but the increase of amount of hydroxyproline was markedly slowed down in 9 month old HS. It was suggested that: (1) in the developing process of HS the proecess of overproliferation of fibroblasts was short and limitted in 1-3 months period in the process of wound lealing; (2) the synthesis of collagen was nearly stopped at 6 months, but that of other extracellular matrix such as fibronectin and proteoglycan might be continued to aggregate after 12 months.
Objective To observe the inhibitory effects of local co-transfection of tissuetype plasminogen activator(tPA) gene and proliferating cell nuclear antigen antisense oligodeoxynucleotides(PCNA-ASODN) on the intima proliferation and restenosis of autograft artery in rabbits. Methods One hundred and twenty male Zelanian rabbits were randomly divided into four groups(n=30, in each group): control group, PCNA-ASODN group, tPA group and tPA+PCNAASODN group. The left and right external iliac arteries (length 1.0 cm) were transplanted reciprocally. The transplanted arteries were respectively soaked in lipofection, PCNAASODN, pBudCE4.1/tPA and pBudCE4.1/tPA+PCNA-ASODN solution about 15 minutes. The transplanted arteries were sutured with 9-0 sutures soaked in PCNA-ASODN and pBudCE4.1/tPA solution. Each group were divided into five subgroups(n=6, in each subgroup) according to the sacrifice time (3 d, 7 d, 14 d, 28 d and 56 d after operation). On every sacrifice time point, the vascular specimens were harvested. The thrombocyte assembling and thrombus forming lining vessel wall were observed by scanning electron microscope. The pathological morphology of transplanted arteries were observed under microscope(HE). The intimal areas and stenosis ratio(%) of transplanted arteries were calculate and analyzed statistically among groups by computer system. The mRNA expression of tPA gene in transplanted ressel wall was detected with vevere transcriptionPCR(RT-PCR). The number of PCNA positive cells in transplanted vessel wall was counted by SP immunochemisty.Results The mRNA expression of tPA gene in the transplanted vessel wall in tPA and tPA+PCNA-ASODN groups was higher than that of the other two groups(P＜0.01).The number of PCNA positive cells in the transplanted arteries in PCNAASODN, tPA and tPA+PCNAASODN groups were significantly lower than that of control group(P＜0.05，P＜0.01). The intimal areas and degrees of luminal stenosis of PCNAASODN, tPA and tPA+PCNAASODN groups were lower than those of control group(P＜0.05，P＜0.01), and those of tPA＋ PCNA-ASODN group were lower than those of PCNA-ASODN and tPA groups(P＜0.05). Scanning electron microscopy showed that there were a few thrombocytes lining the vessel wall of tPA group and tPA+PCNAASODN group and no thrombus, whereas there were abundant thrombocytes and thrombi lining the vessel wall of the control group. Conclusion Co-transfection of tPA gene and PCNA-ASODN can effectively inhibit the proliferation of VSMC, hyperplasia of intima and restenosis of transplanted artery.
Tostudytheexpressionofproliferatingcellnuclearantigen(PCNA)inhumangastricneoplasmanditsclinicalsignificance.TheexpressionofPCNAwassemiquantitativelyanalysedimmunohistochemically(ABC)in10gastricadenomatouspolypand94gastriccarcinomas.Results:①PCNAlabelingindex(LI)showedasignificantdifferentiationindifferentpathologicstate(Plt;0.01),②PCNALIingastriccarcinomawasindepednetofsexandage(Pgt;0.05),butcorrelatedwiththegrowingmannerofthetumor,tumordifferentiation,serosalinfiltration,nodalmetastasisandclinicalstages(Plt;0.05),③ThecorrelationwasfoundbetweenPCNALIandprognosisofgastriccarcinoma(Plt;0.05).AmoderategradeofPCNAexpressiongenerallyhadabetterprognosis.Conclusions:TheseresultssuggestthatPCNALIisafairlygoodindextoindicatebiologicbehaviorandprognosisingastriccarcinoma.
PURPOSE:To investigate the relationship between the proliferative activity of refinoblastoma (RB)cell and the RB differentiation degree and the infiltration capability. METHOD:The proliferating cell nuclear antigen (PCNA)expression in RB tissues of 48 cases was analysed by using LSAB immunohistochemical method. RESULTS :The mean PCNA labelling index(LI)in differentiated RB tissues of 12 cases was markedly lower than that in non-differentiated of 36 cases(P＜0.05). The mean PCNA LI in RB tissues of the optic nerve infiltrated group(22 cases)was significantly higher than that of the optic nerve non-infiltrated group(26 cases)(P＜0.05). The results indicate that the PCNA LI is significantly related with the differentiation degree of RB and the infiltration capability. CONCLUSION :The determination of PCNA LI is of significance for evaluating the histologic characteristics and biological behavior of RB.
Purpose To observe the expression of proliferating cell nuclear antigen（PCNA）and bcl-2 of cultured human retinal pigment epithelial cells（RPE）． Methods SABC techniques were applied for immunocytochemical staining of cultured RPE with mouse anti-human PCNA monoclonal antibody and rabbit antihuman bcl-2 antibodies． Results 31.2% and 50.6% cultured cells were positive to anti-human PCNA at 24h and 48h after seeding，respectively．The positive staining was mottled in the nucleus．positive staining for bcl was seen in 76%to 90% cells as fine granules scattered within the cytoplasm. Conclusion One half of cultured RPE expressed PCNA，indicating that the cells were in phase S of the cell cycle．Positive staining for bcl-2 appeared in much more RPE cells．These biological markers may be associated with the growth activity of cultured RPE． (Chin J Ocul Fundus Dis,1998,14:26-28)
Although deep learning plays an important role in cell nucleus segmentation, it still faces problems such as difficulty in extracting subtle features and blurring of nucleus edges in pathological diagnosis. Aiming at the above problems, a nuclear segmentation network combined with attention mechanism is proposed. The network uses UNet network as the basic structure and the depth separable residual (DSRC) module as the feature encoding to avoid losing the boundary information of the cell nucleus. The feature decoding uses the coordinate attention (CA) to enhance the long-range distance in the feature space and highlights the key information of the nuclear position. Finally, the semantics information fusion (SIF) module integrates the feature of deep and shallow layers to improve the segmentation effect. The experiments were performed on the 2018 data science bowl (DSB2018) dataset and the triple negative breast cancer (TNBC) dataset. For the two datasets, the accuracy of the proposed method was 92.01% and 89.80%, the sensitivity was 90.09% and 91.10%, and the mean intersection over union was 89.01% and 89.12%, respectively. The experimental results show that the proposed method can effectively segment the subtle regions of the nucleus, improve the segmentation accuracy, and provide a reliable basis for clinical diagnosis.