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Using nimotuzumab targeting epidermal growth factor receptor (EGFR) as carrier, we have established a one-step labeling process for 211At and 131I and performed a preliminary treatment study on tumor-bearing mice. The labeling rate both were about 95%, and related radiolabeling complexes could maintain stability in PBS and FBS. The distribution showed that tumor uptake was still maintained to （28.2±4.7） %ID·g-1 after 24 h at intratumoral injection. The therapeutic effect of 131I/211At -ATE-nimotuzumab in U87MG glioma-bearing nude mice was further evaluated. The two labeled drugs can significantly inhibit the growth of solid tumors in a dose-dependent manner with no significant effect on the body weight of mice, effectively prolonging the survival time of subjects. In comparison, the median survival time of tumor-bearing mice in the 211At-ATE-nimotuzumab group at 20 μCi was longer than that in the 131I-ATE-nimotuzumab group at 20 μCi (35 days and 31.6 days). This work further confirmed that the α-nuclide 211At has great potential in the research of radioactive targeted therapy, and can provide an important reference for the preclinical basic research of related drugs.

Ferroptosis and disulfidpthosis are associated with various diseases. Ferroptosis is distinguished by abnormal accumulation of iron ions and lipid reactive oxygen species, while disulfidptosis is marked by abnormal accumulation of disulfides. Solute carrier family 3 member 2 (SLC3A2), a component of the solute carrier family, is implicated not only involved in the regulation of tumor cell proliferation, migration, invasion and apoptosis, but also in the processes of ferroptosis and disulfidptosis, playing a pivotal role in tumor growth and progression. This article provides an overview of the latest advancements in understanding the relationship between SLC3A2 and ferroptosis, disulfidptosis and tumors, aiming to establish a theoretical basis for targeted cancer therapies. [ABSTRACT FROM AUTHOR]

ObjectiveTo analyze the mental health status and the influencing factors among the residents taking standardized residency training during the outbreak and stable period of COVID-19， so as to provide theoretical basis for their mental health education.MethodsOn February 8 to February 10 and April 11 to April 13， 2020， Symptom Checklist 90 （SCL-90）， Beck Srivastava Stress Inventory （BSSI） and Simplified Coping Style Questionnaire （SCSQ） were distributed in online chat groups involving all grades of residents taking standardized residency training in the Second Affiliated Hospital of Kunming Medical University. Through two rounds of questionnaire survey， non-probability sampling method was used to obtain survey samples， and their mental status were analyzed.ResultsA total of 159 valid questionnaires were collected in the first round， and 99 valid questionnaires in the second round. The first survey showed that the total score of SCL-90 was （117.69±37.74） and the detection rate of positive symptoms in SCL-90 was 25.8%， and mainly dominated by obsession， fear and interpersonal sensitivity. In the second survey， the results showed that the total score of SCL-90 was （127.19±51.44）， and the main positive symptoms included obsession， depression and interpersonal sensitivity， with a positive detection rate of 30.3 %. The first survey found that the mental health status had significant differences among residents of different grades （χ2=7.46， P

In this paper, the digital beamforming algorithm for horizontally polarized directional antenna array in narrowband multipath environment is studied. Because the steering vector of directional antenna arrays is complex and cannot be modeled exactly, blind beamforming algorithm is usually used for directional antenna arrays. As the existing blind beamforming algorithms require much prior information, work poorly for weak signals, have limited applications, and need high computational complexity, this paper designs a multi-polarization heterogeneous array cooperative processing scheme, and proposes a new multipath strengthening beamforming algorithm based on adaptive loading projection. The heterogeneous array consists of vertical polarization omnidirectional antenna array and horizontal polarization directional antenna array. The new algorithm utilizes the respective advantages of the two polarization arrays. This algorithm combines the methods of spatial smoothing, sampling matrix inversion, and spatial projection, and further improves the robustness of waveform estimation through adaptive loading processing. The algorithm requires less computation and less prior information, and has strong adaptability to non-ideal conditions. The implementation process and error analysis of the new algorithm are deduced, and effectiveness of the new algorithm is verified through computer simulations.

Objective To detect the protein expression of lysosome-associated protein transmembrane-4 beta (LAPTM4B) in glioma tissues, and to determine its effect on cell proliferation and invasiveness and its correlation with prognosis. Methods A total of 86 glioma patients who underwent surgical resection in our hospital from June 2011 to June 2015 were recruited in this study, and they were followed up till June 30, 2018. In the same period, 25 cases of normal brain tissues were selected. Immunohistochemical assay (SP) was used to detect LAPTM4B protein expression in gliomas and normal brain tissues. Kaplan-Meier analysis and Log-Rank test were performed for survival analysis. Cox proportional hazards model analysis was carried out for risk factors affecting prognosis. U251 cells were cultured and divided into siRNA-LAPTM4B group, siRNA-NC group and blank group. The expression of LAPTM4B in the cells was detected by real-time fluorescent quantitative PCR. Cell proliferation was detected by MTT assay and colony formation assay. Cell migration and invasion was detected by Transwell assay. The protein levels of LAPTM4B, E-cadherin, N-cadherin and Vimentin were detected by Western blotting. Results The positive rate of LAPTM4B protein was 77.91% in glioma tissues, which was higher by 28.00% than that in the normal brain tissues (P < 0.001). The positive expression rate of LAPTM4B protein had statistical difference with different WHO grades (P < 0.05). Kaplan-Meier survival analysis showed that the median survival time and cumulative survival rate were significantly lower in the LAPTM4B-positive group than the negative group (P=0.002). Cox proportional hazard model analysis indicated that WHO classification and LAPTM4B protein expression were risk factors for prognosis of glioma patients (P < 0.05). Compared with the siRNA-NC group and the blank group, the relative expression of LAPTM4B at mRNA and protein levels were decreased in the siRNA-LAPTM4B group (P < 0.05), and the cell proliferation at 24, 48, 72 and 96 h, the numbers of cellular clone, migrated cells and invasive cells, and protein levels of N-cadherin and Vimentin were decreased, while the level of E-cadherin protein was increased in the siRNA-LAPTM4B group (all P < 0.05). Conclusion LAPTM4B protein is highly expressed in glioma tissues, and promotes cell proliferation and invasion, which may be associated with epithelial-mesenchymal transition. Its expression level is correlated with prognosis of the patients.

There is a problem of large measurement error in the front fan drift multi-point measurement method of the air quantity of the main fan currently in use. To solve this problem, the simulation model for three common fan drifts is established, and the variation law of airflow distribution caused by the installation of the wind sensor is analyzed. According to the cloud map of longitudinal velocity distribution in the fan drift, the airflow distribution at the section of the sensor mounting bracket changes dramatically due to the interference of the bracket. After 200 mm of the leading bracket section, the wind velocity distribution tends to be uniform and the influence of the bracket on the airflow is reduced. The influence is minimal at the leading bracket of 250 mm, which can be used as the reference position for the sensor probe installation. Taking the square fan drift as an example, the experimental verification is carried out. The results show that: the measurement error is the greatest when the sensors are installed at the cross-section of the bracket at the selected 8 working points. With the distance increase of the sensor is mounted forward, the measurement error decreases gradually and reaches the minimum at 250 mm.

The VP2 peptide specifically binding to vasoactive intestinal polypeptide receptor 1(VPAC1) receptor was radioiodinated with 131I by bi-functional linker N-succinimidyl 5-(tributylstannyl)-3-pyridinecarboxylate (SPC), and in vitro and in vivo stability of the labeled peptide were evaluated. Mice were injected intravenously with either 1.2×106 Bq 131I-SPC-VP2 or Na 131I. Radiochemical purity and biodistribution were studied at various time points. The result showed that purified 131I-SPC-VP2 exhibited radiochemical purity of 97% at room temperature up to 48 h. The tissue uptake of 131I-SPC-VP2 was low after 6 h injection, especially in thyroid. The result indicated the labeled compound had fast clearance and good stability in vivo.

The experiment studied the screening of α -galactosidase producing strain of Aspergillus niger variants and optimization of fermentation conditions. After UV mutagenesis and subculture of Aspergillus niger strain MX-H, a strain MX-H1 with stable α-galactosidase production was obtained, and its medium for enzyme production was optimized. The 18S rDNA identification showed that strain MX-H1 was identified as Aspergillus niger. The results showed that the optimal conditions were carbon source 15 g/L sucrose, nitrogen source 10 g/L beef extract, the production inducer 0.5 g/L raffinose, the initial pH 6.0, the culture temperature 30 °C, the sample size 30 mL/250 mL and the shaking table 180 r/min for 96 h. Under the optimal conditions, the activity of α-galactosidase was 4.95 U/mL. The experiment provides a reference for industrial production of α-galactosidase. [ABSTRACT FROM AUTHOR]

This study explored the capsule formation and fiber development process of kapok which is a tree in Yuanjiang dry-hot valleys (DHV) using the methods of paraffin section and scanning electron microscopy. The result showed that formation process of kapok capsule can be divided into four stages: the capsule formation within 5 days after anthesis (DAA), the capsule mass period from 5 to 35 DAA, the capsule dehydration period from 35 to 50 DAA, and the capsule bursting period after 50 DAA. The kapok fiber was developed via endocarp cells differentiation (0-2 DAA), swelling (2-5 DAA), bulging (5-10 DAA), fiber elongating (10-40 DAA), and divorcing from pericarp (40 -50 DAA). During the development, the length and projection width of fiber increased as a power function, and their daily average growth rates reached the maximums at 20 DAA. Fiber fresh mass substantially increased and then reduced, and the daily average growth rate reached the maximum in the period from 25 to 30 DAA. Fiber dry mass gradually increased and reached the maximum growth rate in the period from 20 to 25 DAA. The seed and fiber continually increased their mass after 30 DAA, but the pericarp mass declined with its dehydration and aging. Compared with cotton, it was easy to separate fiber from kapok capsule inner wall because of small adhesion power between kapok fiber and capsule inner wall. The period from 5 to 35 DAA was critical for the fiber development and growth. Therefore, water and fertilizer management should be concentrated at this stage. The capsule should be harvested at 50 DAA because the fiber began to divorce from the pericarp. [ABSTRACT FROM AUTHOR]

High-resolution satellite images such as those from Ikonos and QuickBird are increasingly available and are considered a valuable tool for extracting the consequences of gully erosion, and QuickBird imagery has been used to map gully features. To evaluate the accuracy of extracting morphological parameters of bank gullies including area, perimeter, and length from QuickBird imagery by manual visual interpretation, and to analyze the causes of errors, 20 bank gullies were selected in Hegou catchment and Qiaogou catchment located in the Loess Plateau of northern Shaanxi province, respectively. 3D laser scanner was used to measure the topography of bank gullies within two weeks after the QuickBird images were taken. The interval among measurement points of 3D laser scanner was set as 0.15 m. 3D laser scanner had been increasingly used to measure the topography as it can provide a high accuracy, non-contacted, penetrating and rapid method that enables the rapid production of accurate, high-resolution digital elevation model (DEM). Based on Delaunay triangulated irregular networks (TIN), then DEM with the pixel size of 0.15 m × 0.15 m was created using the 3D Analyst extension of ArcGIS 9.3. On this basis, the values of morphological parameters extracted from DEM were taken as actual values and errors of morphological parameters of bank gullies extracted from QuickBird imagery were determined. The average absolute error, maximum absolute error, average relative error, maximum relative error, and maximum relative error among different interpretation persons were used to assess the accuracy of manual visual interpretation of QuickBird imagery. The results showed that maximum relative error of area and perimeter ranged from 4.1% to 22.2% and 1.4% to 22.2% in Hegou catchment, respectively, while maximum relative error ranged from 2.4% to 22.6% for area and 4.5% to 29.7% for perimeter in Qiaogou catchment, respectively. Although maximum relative error appeared to be large for some gullies, average relative error of area and perimeter were both about 5% in two study areas. In addition, by overlaying the two valley regions extracted from QuickBird imagery and DEM, the area that the distance offsets was larger than 0.6 m (QuickBird image one pixel value) remained below 4%. Average relative error of gully length in Hegou catchment and Qiaogou catchment were about 2% and 5%, respectively, with corresponding average of the average absolute error of 0.5 m and 0.75 m. Correlation analysis showed that average relative error, maximum relative error and maximum relative error among different interpretation persons were negatively correlated with the area and length of bank gully (P<0.05), which meant that the larger the area and length of bank gully were, the smaller the errors were. This suggested that choosing large gullies would reduce the errors when the morphological parameters were extracted manually from QuickBird imagery. The accuracy of manual visual interpretation was also influenced by the vegetation types near the gully boundary. Catchments which land was covered with native grassland had higher precision than those were covered with shrub and grass. Overall, QuickBird imagery can provide reliable data source for extracting morphological parameters of bank gullies. The results can provide the references for assessing gully erosion using QuickBird imagery at larger spatial scales rather than direct field measurements. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the effect of matrine on tumor necrosis factor-α(TNF-α)-induced inflammatory response in human umbilical vein endothelial cells(HUVECs) and explore whether the underlying mechanism was related to the miR-25-3p-mediated Krüppel-like factor 4(Klf4) pathway. The HUVEC cell inflammation model was induced by TNF-α stimulation. After 24 or 48 hours of incubation with different concentrations of matrine(0.625, 1.25, and 2.5 mmol·L~(-1)), CCK-8 assay was used to detect cell proliferation. After treatment with 2.5 mmol·L~(-1) matrine for 48 h, the expression of TNF-α, interleukin-6(IL-6), interleukin-1β(IL-1β), and Klf4 mRNA and miR-25-3p was detected by real-time fluorescence-based quantitative PCR, and the protein expression of TNF-α, IL-6, IL-1β, and Klf4 was detected by Western blot. The anti-miR-25-3p was transfected into HUVECs, and the effect of anti-miR-25-3p on TNF-α-induced cell proliferation and inflammatory factors was detected by the above method. The cells were further transfected with miR-25-3p and incubated with matrine to detect the changes in proliferation and expression of related inflammatory factors, miR-25-3p, and Klf4. The targeting relationship between miR-25-3p and Klf4 was verified by bioinformatics analysis and dual luciferase reporter gene assay. The results displayed that matrine could inhibit TNF-α-induced HUVEC proliferation, decrease the mRNA and protein expression of TNF-α, IL-6, and IL-1β, increase the mRNA and protein expression of Klf4, and reduce the expression of miR-25-3p. Bioinformatics analysis showed that there were specific complementary binding sites between miR-25-3p and Klf4 sequences. Dual luciferase reporter gene assay confirmed that miR-25-3p negatively regulated Klf4 expression in HUVECs by targeting. The inhibition of miR-25-3p expression can reduce TNF-α-induced cell proliferation and mRNA and protein expression of TNF-α, IL-6, and IL-1β. MiR-25-3p overexpression could reverse the effect of matrine on TNF-α-induced cell proliferation and the mRNA and protein expression of TNF-α, IL-6, IL-1β, and Klf4. This study shows that matrine inhibits the inflammatory response induced by TNF-α in HUVECs through miR-25-3p-mediated Klf4 pathway.

Objective: To explore the effect and mechanism of down-regulating lncRNA TTTY15 targeting miR-4500 on the proliferation, apoptosis, migration and invasion of A172 glioma cells., Methods: The difference in TTTY15 expression between the glioma cells and tissue was determined with a qRT-PCR method. Complementary binding sites of TTTY15 and miR-4500 were predicted with Starbase software, and the targeting relationship was validated with a luciferase reporter system. A172 glioma cells were divided into Control, si-NC (transfected with control siRNA), si-TTTY15 (transfected with TTTY15 siRNA), si-TTTY15+Anti-miR-NC (co-transfected with TTTY15 siRNA and inhibitor control) and si-TTTY15+Anti-miR-4500 (co-transfected with TTTY15 siRNA and miR-4500 inhibitor) groups. Proliferation, apoptosis, migration and invasion, and the expression of Bax, Bcl-2, MMP-2 and MMP-9 proteins of the A172 glioma cells were respectively detected with CCK-8, flow cytometry, Transwell chamber and Western blotting assays., Results: The expression of TTTY15 in glioma cells and glioma tissues have both increased. The expression levels of TTTY15 and miR-4500 in glioma tissues were inversely correlated. TTTY15 and miR-4500 are mutually targeted. Compared with those of the Control and si-NC groups, the glioma cells in the si-TTTY15 group showed increased level of miR-4500, decreased survival rate, increased apoptosis rate, enhanced cell migration and invasion, increased expression of Bax protein, and decreased expression of Bcl-2, MMP-2 and MMP-9 proteins (P<0.05). Compared with those of the si-TTTY15+Anti-miR-NC group, the A172 glioma cells in the si-TTTY15+Anti-miR-4500 group showed decreased level of miR-4500, increased cell survival rate, decreased apoptosis rate, enhanced cell migration and invasion, decreased expression of Bax protein, and increased expression of Bcl-2, MMP-2, and MMP-9 proteins (P<0.05)., Conclusion: Down-regulating TTTY15 targeting miR-4500 can inhibit the proliferation, migration, invasion and induce apoptosis of the A172 glioma cells.

To explore changes in soil aggregate stability along an elevation gradient, and its regulating factors, soil samples were taken from the 0-10 cm surface layer at 3 different elevations on Taibai Mountain. We measured and analyzed the distribution of soil aggregates, physical and chemical properties, microbial biomass, and extracellular enzymes. The results showed that: ① the soil aggregates from the 3 elevations had mean weight diameters (MWD) of 2.17 mm, 1.83 mm, and 1.82 mm (increasing elevation), and geometric mean diameters (GMD) of 1.66 mm, 1.39 mm, and 1.32 mm, respectively. ② The change in soil aggregate stability along an elevation gradient was regulated by extracellular enzymes in the soil, in particular, the LAP in soil meso-aggregate and the BG in soil micro-aggregate. ③ Microorganisms can alleviate the N limitation at high elevations by adjusting the relative production of extracellular enzymes and altering nutrient utilization efficiency, which also changes soil aggregate stability along an elevation gradient. The results of this study have important scientific significance for soil quality evaluation and ecological environment protection in Taibai Mountain.

This study aimed to discern the effect of different levels of irrigation with reclaimed water on soil enzyme activities and on the distribution of thermotolerant coliforms. The effects of two irrigation water qualities (reclaimed water and tap water) and two irrigation levels (full irrigation and insufficient irrigation) on soil enzyme activity and distribution of thermotolerant coliforms were studied through indoor soil column irrigation. Results indicated that:① Reclaimed water irrigation increased soil urease and invertase activity compared with tap water under the same irrigation conditions. Compared with insufficient irrigation with reclaimed water, full irrigation with reclaimed water significantly increased soil invertase activity and deep soil catalase activity. ② At the same irrigation level, the number of thermotolerant coliforms in soil significantly increased with reclaimed water irrigation. The number of thermotolerant coliforms in soil under full irrigation with reclaimed water was significantly higher than with insufficient irrigation using reclaimed water. The number of thermotolerant coliforms in surface soil of the four irrigated treatments was significantly higher than in the deep soil layer, and with progression of irrigation, the number of thermotolerant coliforms in the 0-60 cm soil layer decreased. ③ There was a significant positive correlation between the quantity of thermotolerant coliforms and the activity of soil urease and invertase, and between the quantity of thermotolerant coliforms and the activity of soil catalase. Reclaimed water therefore promoted enzyme activity that can promote transformation of C and N in soil. Reasonable irrigation with reclaimed water can therefore effectively control the number of thermotolerant coliforms in soil.

Objective: To summarize the 23-year experience of laparoscopic biliary surgery in General Hospital of PLA and evaluate the application of laparoscopic surgery in the treatment of biliary diseases., Methods: We retrospectively analyzed the clinical data of 11 419 consecutive patients with biliary diseases undergoing laparoscopic surgery from April, 1992 and December, 2014. The disease spectrum was compared between patients treated before December 31, 2003 and those treated after the time point., Results: The 11419 patients receiving laparoscopic surgery accounted for 56.3% of the total patients undergoing biliary surgeries during the 23 years, including 4701 male and 6718 female patients with a mean age of 50.9∓13.2 years (6-93 years). Most (80.83%) of the patients received laparoscopic surgery for gallbladder stones, and 12.53% patients had the operation for gallbladder polyps. The laparoscopic operation rate was 84.81% in patients with gallbladder stones and 34.91% in patients with extrahepatic bile duct stones, but remained low in patients with biliary carcinoma. In laparoscopic operations, laparoscopic cholecystectomy was the most frequent (96.18%) followed by operations for extrahepatic bile duct stones, in which primary suture accounted for 1.38%, traditional T tube drainage for 0.90% and laparoscopic transcystic duct exploration for 0.72%. For malignant tumors, laparoscopic technique was used mainly for the purpose of exploration (0.34%). The application of laparoscopic technique in biliary surgery tended to increase after the year 2004, especially for benign gallbladder diseases and extrahepatic bile duct stones (P<0.05)., Conclusion: Laparoscopic technique in biliary surgery is gradually replacing the traditional open operation and becomes the gold standard for the treatment of benign biliary diseases.

This study explored the capsule formation and fiber development process of kapok which is a tree in Yuanjiang dry-hot valleys (DHV) using the methods of paraffin section and scanning electron microscopy. The result showed that formation process of kapok capsule can be divided into four stages: the capsule formation within 5 days after anthesis (DAA), the capsule mass period from 5 to 35 DAA, the capsule dehydration period from 35 to 50 DAA, and the capsule bursting period after 50 DAA. The kapok fiber was developed via endocarp cells differentiation (0-2 DAA), swelling (2-5 DAA), bulging (5-10 DAA), fiber elongating (10-40 DAA), and divorcing from pericarp (40-50 DAA). During the development, the length and projection width of fiber increased as a power function, and their daily average growth rates reached .the maximums at 20 DAA. Fiber fresh mass substantially increased and then reduced, and the daily average growth rate reached the maximum in the period from 25 to 30 DAA. Fiber dry mass gradually increased and reached the maximum growth rate in the period from 20 to 25 DAA. The seed and fiber continually increased their mass after 30 DAA, but the pericarp mass declined with its dehydration and aging. Compared with cotton, it was easy to separate fiber from kapok capsule inner wall because of small adhesion power between kapok fiber and capsule inner wall. The period from 5 to 35 DAA was critical for the fiber development and growth. Therefore, water and fertilizer management should be concentrated at this stage. The capsule should be harvested at 50 DAA because the fiber began to divorce from the pericarp.

Objective: To evaluate the effects of structured triglycerides in parenteral nutrition versus a physical medium-chain triglycerides (MCT)/long-chain triglycerides (LCT) mixture on severe hemorrhagic shock patients after resuscitation., Methods: In a randomized trial, we studied 20 critical patients with a total blood loss of over 3000 ml perioperatively and/or intraoperatively. The use of triglycerides started from Day 3 postoperation and parenteral nutrition lasted for no less than 5 days. They were allocated to receive one of two nutrition regiments: structured triglycerides in Group A (n = 10) and MCT/LCT in Group B (n = 10). There were no significant differences of general conditions in two groups. Before the start of parenteral nutrition (d0), d1 d3 and d5 after start of infusion, the following parameters were measured: hemoglobin (Hb), platelet count (Plt), alanine aminotransferase (ALT), total bilirubin (TB), direct bilirubin (DB), serum triglycerides (TG), prealbumin (PA) and transferrin (TF). And mean artery pressure (MAP), heart rate (HR) and central vein pressure (CVP) were also recorded at the same time-points. Then the post-TG changes of the above data were compared in both groups., Results: After the use of triglycerides, there were no significant differences of MAP, HR, CVP, Hb and Plt in both groups (P > 0.05). At D3 and D5, the serum levels of TG ((2.1 ± 0.4) vs (1.6 ± 0.6) mg/L, (2.3 ± 0.7) vs (1.5 ± 0.3) mg/L) and alanine aminotransferase ((133 ± 58) vs (97 ± 26) U/L; (116 ± 48) vs (77 ± 31) U/L) were significantly higher in Group B versus those receiving structured triglycerides in Group A (P < 0.05). TB ((18 ± 15) vs (18 ± 11) µmol/L) and DB ((8.9 ± 3.2) vs (8.8 ± 2.5) µmol/L) had no significant differences in two groups (P > 0.05). The serum levels of such nutrition markers as PA ((195 ± 55) vs (166 ± 55) mg/L,(245 ± 53) vs (195 ± 58) mg/L) and TF ((2.6 ± 0.5) vs (2.5 ± 0.6) g/L, (3.3 ± 0.8) vs (2.9 ± 0.6) g/L)were significantly higher in Group A than those in Group B (P < 0.05)., Conclusion: With regards to lipid metabolism, protein synthesis and hepatocyte protection, structured triglycerides in parenteral nutrition is advantageous to standard MCT/LCT emulsion in severe hemorrhagic shock patients after resuscitation.

Our previous studies showed that tandem Alu repeats inhibited GFP gene expression when they were inserted into the downstream of GFP gene in pEGFP-C1 vector and HeLa cells were then transfected transiently. The sequence named 2F2R (second 60 bp from the 5' end of SV40PolyA antisense strand) eliminated the repression of GFP gene expression induced by Alu repeats when 2F2R was inserted between GFP and Alu repeats. In this study the deletion of 2F2R DNA showed that 45R (45 bp in 2F2R 5'end), 30R (30 bp in 2F2R 5' end) and 22R (22 bp in 2F2R 5' end) activated GFP gene expression, and the activating actions of the double tandem sequences were stronger than those of their corresponding single sequences. Secloop (22 bp near the center in 2F2R) and Poly4 (30 bp in 2F2R 3' end) sequences did not activate GFP gene expression. The activating action of 30R-Poly4 sequence formed by ligating 30R with Poly4 by 9 bp was lower than that of 2F2R. The linking base number between two 22R sequences did not influence the GFP gene expression obviously. Sequence 22R (5'-GTGAAAAAAATGCTTTATTTGT-3') contains an imperfect palindrome sequence and may form an imperfect stem-loop structure including a 3nt loop, 3 bp first stem, 2nt bulge, and 3bp second stem. The mutations changing stem-loop structure of 22R influenced the GFP gene activation significantly and neither the excessively stable nor excessively unstable stem-loop structures were in favour of GFP gene activation, which suggested that the suitably imperfect stem-loop structures had something with gene activation.

Objective: To study the secondary metabolites of mangrove endophytic fungus BL321., Methods: The compounds were isolated by chromatographic technique. The structures were identified by comprehensive physico-chemical properties and spectral methods., Results: Five compounds were isolated and identified as 3,4a-dimethyl-2-oxo-2,4,4a,5,6,7-hexahydronaphtho[2,3-b]furan-5-carboxylic acid(1), cytochalasin C(2), cytochalasin D(3), 19,20-epoxycytochalasin C(4), ergosterol(5)., Conclusion: Compound 1 is isolated from nature for the first time. Further more, several kinds of strong bioactive compounds were islolate from this fungus indicate that it may develop to be medical source microorganism.

With indigenous zinc smelting waste residue, contaminated soil and background soil as test substrates, a pot experiment was conducted to study the growth characteristics of Lolium perenne and Trifolium pretense on these substrates. The results showed that the major limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou were the salt-alkali stress and the lower contents of organic matter, total N, available N and total K. The heavy metals in waste residue had a high concentration, but their available forms only occupied a small proportion, with low toxicity to plant but having potential harmful risk. Contaminated soil had lower concentrations of heavy metals than waste residue, but its contained heavy metals were more in available form. The constraints of revegetation on contaminated soil were the toxicity of heavy metals and the low contents of available P and K. Mixing contaminated soil with zinc smelting waste residue could be one of the effective approaches for the substrate amendment in indigenous zinc smelting areas.