The ultrastructural localization of acid phosphatase in the cells of mouse thymic cortex was described by using Robinson and Karnovsky method with cerium chloride as capture agent. The results indicated that the enzyme activity was localized mainly on the plasma membrane of epithelial reticular cells and thymocytes, especially where both of them were in contact with each other. Acid phosphatase activity was also found in the invaginations of plasma membrane, the vesicles near the plasma membrane, the saccules of the Golgi zone, the lysosomes, and a part of the vacuoles of epitheleial reticular cells. The lysosomes and the dense granules of cytoplasm, as well as on the some area of plasma membrane of the macrophages showed the enzyme activity. The enzyme activity was demonstrated in the cytoplasm and on the plasma membrane of degenerated thymocytes. The role of acid phosphatase in thymic cortex cells was discussed.

The thymic cortex is the important site for thymocyte differentiation, maturation and selection. Direct cell-cell interactions between thymocytes and distinct stromal cells are an important pattern to demonstrate the essential role in T-cell development. In order to approach the mechanism of their interactions, ultrastructural cytochemical localization of 5'-nucleotidase activity in the thymic cortex of BALB/c mice were investigated by means of Robinson and Karnovsky method using 5'-AMP or 5'-IMP as the substrate, cerium as the capture agent, and levamisol (an inhibitor of nonspecific alkaline phosphatase) was also used. The cytochemical distribution of the reaction products from both the 5'-AMPase and 5'-IMPase activity was essentially similar. The enzyme activity was localized on the extracellular side of the plasma membrane of the epithelial reticular cells and some thymocytes, especially on their contact faces with each other. 5'-nucleotidase activity was also found in the lysosomes of macrophages and in the vacuoles, and vesicles near the plasma membrane and some lysosomes of epithelial reticular cells. The biological significance of the 5'-nucleotidase in thymic cortex was discussed.

Fresh cryostat sections from the thymus of BALB/c adult mice were processed with semipermeable membrane technique for demonstration of non-specific esterase (NE). The various cell types and the pattern of their distribution may be showed, because this technique may preserve the total enzyme activity of cells. The NE activity of epithelial reticular cells (ERC), thymic nurse cells (TNC), and interdigitating cells (IDC) are lower, but macrophages (M?) show a high activity. Cortical ERCs appear as a sponge-like network. Medullary ERCs may be divided into two cell types, i. e. low and high activity cells. The distribution of the latter shows foci-like pattern. M? present in both the cortex and medulla, in the cortico-medullary border they are prominent and may form rosettes-like structure with thymocytes. The thymus was also studied with immunohistochemical method using the monoclonal antibody of rat-anti-mouse thymic stromal ceils (MTS-6). This observation enable studies on the type of thymic stromal cells formed thymic microenvironment under LM.

Objective: To study on the mRNA expression level of IN1 gene associated with the clinical efficacy and prognosis of hepatoblastoma(HB) in children and to elucidate the early warning value of IN1 gene for prognosis and chemotherapy sensitivity. Methods: Forty HB patients were selected based on primary diagnosis and treated from January 2015 to May 2018 in Tongren Hospital Affiliated to Capital Medical University. The expression level of INI1 gene was detected by using fluorescence immuno-PCR. Clinical data of children with HB were collected, including staging, grouping, risk, efficacy and prognosis of chemotherapy. The relationship between the mRNA expression of IN1 gene and clinical data was analyzed by SPSS 21.0 software. Results: (1)Clinical characters: the medium age of 40 HB patients was(30.50±2.39) months, male 29 cases (72.5%), and female 11 cases (27.5%). There was 1 case (2.5%) of stage Ⅱ HB, 13 cases (32.5%) of stage Ⅲ HB, and 26 cases (65.0%) of stage Ⅳ. The low-and intermediate- risk group had 12 cases (30.0%) of HB, and the high-risk group had 28 cases (70.0%) of HB.(2)Clinical efficacy and prognosis: by July 1^st, 2018, the medium following-up time was (12.2±10.1) months, 4 patients (10%) were treated by chemotherapy without surgery, and 36 patients (90%) were treated by surgery .All patients (100%) received chemotherapy.The average cycle of chemotherapy lasted(13.17±0.02). Ten patients were dead and 30 patients survived till following-up.The overall survival (OS) rates were 75% and the event-free survival rates were 50% (20 patients with HB). (3) IN1 gene mRNA expression: The average PCR quantitative of IN1 gene mRNA of 40 HB patients(2^-ΔCT)was 0.31±0.70.The average mRNA quantitative of HB patients (2^-ΔCT)with high-risk and low/intermediate-risk group was 0.23±0.43 and 0.48±1.13(t=6.363, P=0.05). According to histology diagnosis, the average mRNA quantitative of small cell undifferentiated (SCU) type (12 cases)and other type (25 cases) was 0.09±0.11 and 0.43±0.86(t=4.533, P=0.04). The average mRNA quantitative of patients with or without radical surgery was 0.04±0.03 and 0.34±0.74 (t=2.935, P=0.022). The data of children with poor chemotherapy sensitivity(19 cases)and those sensitive to chemotherapy (21 cases) were 0.03±0.04 and 0.30±0.82, and the difference was statistically significant (t=5.688, P=0.018). Conclusions Poor therapeutic effect results in low mRNA expression of IN1 gene in children of HB.The IN1 gene expression could be an early warning factor for treatment sensitivity and prognosis.