Objective To investigate the impact of Toxoplasma gondii type I, II and III rhoptry protein 16 (ROP16) on programmed cell death ligand 1 (PD-L1) expression in lung adenocarcinoma cells, and to examine the effects of T. gondii type I ROP16 protein on the relative PD-L1 expression, the relative PD-L1 distribution on the cell membrane surface, and the binding of programmed cell death 1 (PD-1) to PD-L1 in lung adenocarcinoma cells. Methods Lentiviral vectors overexpressing T. gondii type I, II and III ROP16 proteins were generated, and transfected into the human lung adenocarcinoma A549 cell line. A549 cells were used as a blank control group, and A549 cells transfected with an empty lentiviral expression vector were used as a negative control group, while A549 cells transfected with lentiviral vectors overexpressing T. gondii type I, II and III ROP16 proteins served as experimental groups. Stably transfected cells were selected with puromycin and verified using Western blotting, quantitative real-time PCR (RT-qPCR), and immunofluorescence assays. The PD-L1 expression was quantified at translational and transcriptional levels using Western blotting and RT-qPCR assays in A549 cells in the five groups, and the relative PD-L1 distribution was detected on the A549 cell membrane surface using flow cytometry. In addition, the effect of T. gondii type I ROP16 protein on the PD-1/PD-L1 binding was measured in A549 cells using enzyme-linked immunosorbent assay (ELISA). Results The relative ROP16 protein expression was 0, 0, 1.546 ± 0.091, 1.822 ± 0.047 and 2.334 ± 0.089 in the blank control group, negative control group, and the T. gondii type I, II and III ROP16 protein overexpression groups (F = 1 339.00,P < 0.001), and the relative ROP16 mRNA expression was 2.153 ± 0.949, 2.436 ± 1.614, 14.343 ± 0.020, 12.577 ± 0.285 and 15.090 ± 0.420 in the blank control group, negative control group and the T. gondii type I, II and III ROP16 protein overexpression groups, respectively (F = 483.50,P < 0.001). The ROP16 expression was higher in the T. gondii type I, II and III ROP16 protein overexpression groups than in the blank control group at both translational and transcriptional levels (allP values < 0.001). Immunofluorescence assay revealed that T. gondii type I, II and III ROP16 proteins were predominantly localized in A549 cell nuclei. Western blotting showed that the relative PD-L1 protein expression was 0.685 ± 0.109, 0.589 ± 0.114, 1.007 ± 0.117, 0.572 ± 0.151, and 0.426 ± 0.116 in the blank control group, negative control group, and the T. gondii type I, II and III ROP16 protein overexpression groups (F = 9.46,P < 0.05), and RT-qPCR assay quantified that the relative PD-L1 mRNA expression was 1.012 ± 0.190, 1.281 ± 0.465, 1.950 ± 0.175, 0.889 ± 0.251, and 0.230 ± 0.192 in the blank control group, negative control group, and the T. gondii type I, II and III ROP16 protein overexpression groups (F = 14.18,P < 0.05). The PD-L1 expression was higher in the T. gondii type IROP16 protein overexpression group than in the blank control group at both translational and transcriptional levels (both P values < 0.05). Flow cytometry detected that the relative distributions of PD-L1 protein were (10.83 ± 0.60)%, (11.23 ± 0.20)%, and (14.61 ± 0.50)% on the A549 cell membrane surface (F = 28.31, P < 0.05), and the relative distribution of PD-L1 protein was higher in the T. gondii type IROP16 protein overexpression group than in the blank control group and negative control group (both P values < 0.001). ELISA measured significant differences in the absorbance (A) value among the T. gondii type IROP16 protein overexpression group, the blank control group and the negative control group if the concentrations of the recombinant PD-1 protein were 0.04 (F = 10.45, P < 0.05), 0.08 μg/mL (F = 11.68, P < 0.05) and 0.12 μg/mL (F = 52.68, P < 0.05), and the A value was higher in the T. gondii type IROP16 protein overexpression group than in the blank control group and the negative control group (both P values < 0.05), indicating that T. gondii type IROP16 protein promoted the PD-L1/PD-1 binding in A549 cells in a concentration-dose manner. Conclusions T. gondii type IROP16 protein overexpression may up-regulate PD-L1 expression in A549 cells at both transcriptional and translational levels and the relative PD-L1 distribution on the A549 cell membrane surface, and affect the PD-1/PD-L1 binding in a concentration-dependent manner.

Objective    To investigate the optimal administration combination of β-aminopropionitrile (BAPN) and Angiotensin Ⅱ (Ang-Ⅱ) in the establishment of SD rat aortic dissection (AD) model and the related complications. Methods    Forty-two three-week-old male SD rats were randomly divided into 7 groups: a group A (0.25% BAPN), a group B (0.40% BAPN), a group C (0.80% BAPN), a group D [1 g/(kg·d) BAPN], a group E [1 g/(kg·d) BAPN+ 1 μg/(kg·min) saline], a group F [1 g/(kg·d) BAPN+1 μg/(kg·min) Ang-Ⅱ] and a group G (control group). There were 6 rats in each group. The intervention period was 4 weeks (groups E and F were 4 weeks+5 days). Rats were dissected immediately if they died during the experiment. After the intervention, the surviving rats were sacrificed by pentobarbital sodium, and the whole aorta was separated and retained. Hematoxylin-eosin staining was used to observe the changes of aorta from the pathological morphology. Results    There was no statistical difference in the survival rate among the groups after 4 weeks of BAPN intervention (P>0.05). After 5 days of mini-osmotic pumps implantation, the survival rate of rats was higher in the group E than that in the group F (P=0.008), and the incidence of AD in the group E was lower than that in the group F (P=0.001). BAPN could affect the food and water intake of rats. After BAPN intervention for 4 weeks, the body weight of rats in the group G was higher than those in the intervention groups (P<0.05). BAPN combined with Ang-Ⅱ could make the aortic intima thick, elastic fiber breakage, arrangement disorder, and inflammatory cell infiltration in rats, which conformed to the pathological and morphological changes of AD. BAPN could also affect mental state and gastrointestinal tract. Conclusion    The combination of BAPN [1 g/(kg·d)] and Ang-Ⅱ [1 μg/(kg·min)] can stably establish AD model in rats, which will provide a stable carrier for further study of the pathogenesis and therapeutic targets of AD. However, the complications in this process are an unstable factor. How to balance the influence of BAPN on other tissues and organs in the process of AD model establishment remains to be further studied.

OBJECTIVETo investigate the significance of beta-adrenergic receptor 2 (beta2-AR) and vascular endothelial growth factor-2 (VEGFR-2) in the occurrence and development of infantile hemangioma through detecting the expression of beta2-AR and VEGFR-2 in the different stages of infantile hemangiomas.

METHODSAccording to the Mulliken's classification standard, we classified the specimens as proliferating group (32 cases), involuting group (17 cases) and involuted group (11 cases). Normal skin tissue surrounding the hemangioma from 7 cases were chosen as control group. The expression of beta2-AR and VEGFR-2 was detected by immunohistochemical technique in proliferating hemangioma, involuting hemangioma, involuted hemangioma. The mean optical density was measured by image analysis system (Image Pro Plus 6.0) and SPSS 16.0 software was applied for statistical analysis.

RESULTSThe expression of beta2-AR and VEGFR-2 was strongly positive in proliferating hemangioma, while positive in involuting hemangioma and weakly positive in the involuted stage. The mean optical density of each phase was 0.064 751 2 +/- 0.012 747, 0.031 6017 +/- 0.006 848,0.011 869 8 +/- 0.039 349 for beta2-AR, and 0.068 940 9 +/- 0.029 274, 0.028 445 5 +/- 0.006 396, 0.011 184 1 +/- 0.004 198 for VEGFR-2. The differences between different stages had a statistically significance (P < 0.05). Correlation analysis on the mean optical density between beta2-AR and VEGFR-2 had a statistically significance (P < 0. 05).

CONCLUSIONSBeta2-AR and VEGFR-2 may be involved in the occurrence and development of infantile hemangioma.

Child ; Child, Preschool ; Female ; Hemangioma ; metabolism ; Humans ; Infant ; Male ; Receptors, Adrenergic, beta-2 ; metabolism ; Receptors, Vascular Endothelial Growth Factor ; metabolism

Penicillium decumbens T. is an important filamentous fungus for the production of cellulases to effectively degrade lignocellulose for second generation biofuel production. In order to enhance the capability of Penicillium decumbens to produce cellulases, we constructed a creB (a deubiquitinating enzyme encoding gene) deletion cassette, and generated a creB knockout strain with homologous double crossover recombination. This mutation resulted in a detectable decrease of carbon catabolite repression (CCR) effect. The filter paper activity, endoglucanase activity, xylanase activity and exoglucanase activity of the deltacreB strain increased by 1.8, 1.71, 2.06 and 2.04 fold, respectively, when comparing with the parent strain Ku-39. A 2.68 fold increase of extracellular protein concentration was also observed. These results suggest that the deletion of creB results in CCR derepression. These data also suggest that CREB influences cellulase production of Penicillium decumbens. In generation, this study provides information that can be helpful for constructing cellulase hyper-producing strain.
Cellulase ; biosynthesis ; Endopeptidases ; genetics ; metabolism ; Gene Knockout Techniques ; Lignin ; metabolism ; Mutant Proteins ; metabolism ; Penicillium ; enzymology ; genetics ; Recombination, Genetic ; Ubiquitinated Proteins ; genetics ; Ubiquitination

Objective To discuss the value of video-assisted thoracoscopic repair in the treatment of pectus excavatum in children.Methods Thoracoscopic sternum elevation with an internal steel bar(Nuss procedure) was performed in 45 children with pectus excavatum.Preoperatively,a curved steel bar was prepared and the site of incision and the lowest part of the depression were labeled with methylene blue.Under right-sided thoracoscopic vision,the bar was inserted into the retrosternal tunnel thereby correcting deformity. Results The steel bar was placed safely in all the 45 patients.The operation time was 35~80 min(mean,60 min).The intraoperative blood loss was less than 5 ml.The length of postoperative hospital stay was 4~10 days(mean,7 days).Forty children were followed for 3~30 months(mean,16.5 months).Short-term complications included pneumothorax in 1 patient and pneumonia in 1 patient.Long-term complications included bar shift after 1 year in 1 patient and persistent sternal pain in 2 patients(which had been cured by oral and local analgetic administration).The bar had been removed in 10 children,all of whom had good cosmetic results.Conclusions Video-assisted thoracoscopic Nuss procedure is safe and effective in the management of pectus excavatum in children,with advantages of short operation time,simple performance,satisfactory cosmetic results,and fewer complications.

A modification of Watkinson's method was used for the flaorimetric determination of selenium in blood, hair, urine and animal tissues with 2,3-Di-aminonaphthalene. A mixture of sulphuric, perchloric acid and sodium molybdate was used for digestion. As little as 3 ng selenium in the sample could be estimated out. Coefficients of variation and recoveries for blood, hair, urine and animal tissues were 3.9, 5.5, 3.3 and 5.6%, and 97.0, 95.0, 97.8 and 99.8% respectively. No significant difference in selenium content estimated was found as graded amounts of samples were taken for analysis, indicating no foreign interference in the extracts. Both precision and accuracy of this method are satisfactory.

2,3-Diaminonaphthalene was used for the fluorometric determination of selenium in cereals and vegetables. Nitric-perchloric-sulphuric acids mixture was used for digestion. Coefficient of variation and recovery for cereals were 4-10% and 97.1%, and for vegetables were 4-18% and 97.8% respectively. Addition of hydrochloric acid to the final digests could be omitted for ordinary cereals and soybean, but it was necessary for samples from seleni-ferous area and some vegetables with higher selenium content such as mushrooms.

The average daily selenium intake of staff of the Institute of Health in Beijng was surveyed to be 66.4?g and that of children in nursery and kindergarten was 34.7?g, which could meet the Recommended Dietary Allowance as suggested. Cereals were the major source of dietary selenium which accounted for 63.6% of total dietary intake, and animal and plant foods provided about 25.9% and 10.5% respectively. Both cereals and animal foods were the major sources of selenium in children diet, which accounted for 48.9% and 44.3% respectively, and intake of selenium from other sources was negligible.The selenium concentrations in whole blood and hair of the population were 0.146ppm and 0.578ppm respectively, and both correlated well with the daily selenium intake.The daily intake of mercury, arsenic, and cadmium for population in Beijing were estimated to be 3.4, 52.7, and 42.7*g respectively, which were within the normal range of intake and would not significantly interfere with the bioavailability of selenium ingested. It was suggested thal these levels of selenium daily intake surveyed would be adequate for human consumption and could be helpful as a reference for the establishment of dietary allowance.

The content of selenium and several antagonistic metals such as mercury, arsenic, and cadmium in foods from Beijing market has been determined. Results showed that marine products, Viscera (particularly kidney), eggs, and mushroom were good dietary sources of selenium. The selenium contents of imported cereals and pulse are much higher than those grown in China as far as the sample analysed. Most vegetables and fruits contained selenium below a level of 0.010ppm with exception of garlic and mushroom.The selenium content of human milk was higher than other kinds of milk, milk products and milk-substitutes. Selenium content of Beijing foods was far higher than those in affected area of Keshan disease. The mercury, arsenic, and cadmium content of foods was below the National Allowance Standard except a few marine products.The selenium content of natural plant foods was positively correlated with its protein content (r=0.844, p

Results obtained from previous studies shoved that at low level of dietary selenium(0.03 ppm) weanling rats fed with diets of low protein level usually possessed higher selenium concentration and GSHPx activity in their blood and tissues. The results were reproduced in chickens in this observation. Furthermore, even the original selenium level could not be maintained in blood and tissues of chickens fed with low protein diet (12.4%) because of faster growth rate and the lower selenium content (0.01 ppm) of the diet used in this study.Of the 27 chickens consuming 18.2% protein diet in the 14 days expe- riment, 23 suffered from exudative diathesis and 3 died without any sign of exudative diathesis, while in the 12.4% protein group only one of the 26 chickens suffered from exudative diathesis during the 14 days experiment and 6 of the 12 chickens in this group observed for another two weeks showed exudative diathesis. In the 18.2% protein group the first chicken with signs of exudative diathesis appeared on the 9th day while it appeared on the 14th day in the 12.4% protein group.How to improve the selenium nutritional status of the residents in Ke-shan Disease areas was discussed.