Tibial adamantinoma with local recurrence and pulmonary metastasis: report of a case with histocytologic findings

BACKGROUND: Adamantinoma is a rare primary bone neoplasm of low malignant potential that may recur or metastasize in a mall percentage of patients. The myriad histologic patterns may cause difficulty in distinguishing this tumor from other primary or metastatic neoplasms. The cytomorphologic findings of fine needle aspiration biopsy were reported previously in only a small number of cases. CASE: A 32-year-old man presented with a mass in the distal side of the left leg that was diagnosed as classic adamantinoma by open biopsy. Local recurrence and pulmonary metastases were confirmed by fine needle aspiration biopsy, which showed low grade, uniform cells with nuclear membrane grooves. The patient underwent a below-the-knee amputation and is receiving palliative treatment for progressive pulmonary spread. CONCLUSION: The diagnosis of adamantinoma requires knowledge of compatible clinical and radiologic studies as well as understanding of the variable histologic patterns that one may encounter. Fine needle aspiration biopsy is particularly useful in the diagnosis of recurrent and metastatic adamantinoma. This case report describes a distinctive cytomorphologic feature of nuclear grooves that may be a useful aid in distinguishing the tumor cells of adamantinoma from other cell types.     

枯草芽孢杆菌ccpA基因敲除及对其核黄素产量的影响

CcpA蛋白是介导枯草芽孢杆菌碳分解代谢物阻遏(CCR)的全局调控因子,由ccpA基因编码。CCR效应的存在影响B.subtilis对葡萄糖的利用,降低B.subtilis生产发酵产品的效率。采用基因重组技术敲除了核黄素发酵菌株B.subtilis24/pMX45的ccpA基因,构建了CcpA缺陷株B.subtilis24A1/pMX45。发酵结果显示:B.subtilis24A1/pMX45能够在70h内基本耗尽10%的葡萄糖,生物量达到1.5×109个细胞/mL,溢流代谢产物积累量减少,在8%和10%葡萄糖浓度下,B.subtilis24A1/pMX45核黄素产量分别比B.subtilis24/pMX45提高了62%和95%。CcpA的缺陷,可以缓解葡萄糖引起的CCR效应,显著提高菌株的核黄素产量。     

过表达E2F6基因抑制BRD7基因启动子活性

BRD7基因是采用cDNA代表性差异分析法克隆的一个新Bromodomain基因(GenBank 登录号AF152604)。它在鼻咽癌细胞和组织中表达明显下调,过表达BRD7基因可抑制鼻咽癌细胞的生长和细胞周期的进程。前期工作已克隆了BRD7基因启动子区,并将其启动子定位于450bp（-404→+46bp）的区域。为了进一步揭示BRD7基因在鼻咽癌细胞和组织中表达下调的分子机制,生物信息学分析表明BRD7启动子区有E2F6转录因子结合位点,电泳迁移率实验结果表明转录因子E2F6特异性地结合于BRD7启动子区。荧光素酶检测和绿色荧光蛋白表达检测都证实过表达E2F6基因能抑制BRD7基因启动子活性     

一种农杆菌介导的赤霉菌CCRC3.572的转化方法

目的:建立农杆菌Ti质粒介导的转化赤霉菌的新方法。方法:以农杆菌Ti质粒pCAMBIA0390为基础,构建带有潮霉素抗性基因表达盒的双元载体,并用农杆菌介导的方法转化赤霉菌。结果:构建了双元载体pCAMBIA0390-hph(PgpdA),并获得了具有潮霉素抗性的赤霉菌转化子。结论:农杆菌介导的方法适于赤霉菌的转化,为赤霉菌的遗传研究提供了一种新的手段。     

抗人胎盘酸性铁蛋白单链抗体的构建、表达与鉴定

目的:制备人胎盘酸性铁蛋白(PAF),构建、表达并鉴定抗人PAF单链可变区抗体片段(scFv)。方法:设计以SfiⅠ、NotⅠ为酶切位点、以(Gly4Ser)3为linker的2对引物,从抗人PAF单克隆抗体可变区基因的克隆载体中扩增VH和VL基因,用重叠延伸PCR在VH和VL基因间引入连接短肽,构建VH-linker-VL的scFv基因。经SfiⅠ、NotⅠ酶切后克隆到原核分泌型表达载体pUC19/119上,转化大肠杆菌TG1和筛选后测序验证,IPTG诱导表达,SDS-PAGE鉴定其相对分子质量(Mr)。以人PAF为抗原,scFv为一抗,抗His单克隆抗体为二抗,间接ELISA鉴定其抗体活性。结果:重叠延伸PCR扩增产物经凝胶电泳可见约700bp的条带,DNA序列分析证明2株抗体具有完整的scFv序列,并含有c-myc和His。IPTG诱导阳性菌表达产物经SDS-PAGE鉴定有Mr约27000的显示条带,符合scFv与表达标签融合蛋白的理论值;间接ELISA证明表达产物可与PAF结合。结论:成功构建并表达了抗人PAF单链抗体,为进一步建立检测PAF的间接ELISA奠定了基础。     

Plastid transformation in the monocotyledonous cereal crop, rice (Oryza sativa) and transmission of transgenes to their progeny

The plastid transformation approach offers a number of unique advantages, including high-level transgene expression, multi-gene engineering, transgene containment, and a lack of gene silencing and position effects. The extension of plastid transformation technology to monocotyledonous cereal crops, including rice, bears great promise for the improvement of agronomic traits, and the efficient production of pharmaceutical or nutritional enhancement. Here, we report a promising step towards stable plastid transformation in rice. We produced fertile transplastomic rice plants and demonstrated transmission of the plastid-expressed green fluorescent protein (GFP) and aminoglycoside 3'-adenylyltransferase genes to the progeny of these plants. Transgenic chloroplasts were determined to have stably expressed the GFP, which was confirmed by both confocal microscopy and Western blot analyses. Although the produced rice plastid transformants were found to be heteroplastomic, and the transformation efficiency requires further improvement, this study has established a variety of parameters for the use of plastid transformation technology in cereal crops.     

Proteomics-based identification of autoantibodies in the sera of healthy Chinese individuals from Beijing

The identification of panels of tumor antigens that elicit an antibody response may have utility in cancer screening, diagnosis and in establishing prognosis. However, autoantibodies normally exist in sera of healthy individuals and are enormously diversified. To explore the reservoir of autoantibody in healthy population, we performed a proteomics investigation of autoantibody profiles in the sera of 36 healthy Chinese individuals from Beijing, which may provide valuable reference information to the identification of disease-specific autoantibodies. The results showed that autoantibody profiles varied individually, but some autoantibodies were identified at a high frequency in the healthy population. The autoantibodies against alpha-enolase and those against heterogeneous nuclear ribonucleoprotein L were positive in more than 50% of the sera samples. The autoantibodies identified in more than 20% of samples included those against annexin II, F-actin capping protein beta subunit and calreticulin. Some of these autoantibodies have been previously reported to be involved in autoimmune conditions and cancers. Autoantibodies in the healthy population are important as a foundation from which disease-specific autoantibodies can be defined. Thus our report on autoantibodies in healthy individuals may be useful as a reference for defining new autoantibody biomarkers.     

鱼腥藻PCC7120藻蓝蛋白α亚基体内重组研究

为了研究藻蓝蛋白α亚基的生物合成途径,通过构建相容的3种重组质粒pETDuet-cpcA、pCOLADuet-cpcE-cpcF和pACYCDuet-ho1-pcyA,将裂合酶基因cpcE和cpcF、血红素氧化酶基因ho1、藻蓝胆素合成酶基因pcyA和脱辅基藻蓝蛋白α亚基基因cpcA共同转入大肠杆菌BL21(DE3)。通过色素蛋白锌电泳和光谱检测表明产生了生物活性的CpcA-PCB。成功实现了大肠杆菌内藻蓝蛋白α亚基84位半胱氨酸残基与PCB的连接。而在裂合酶基因cpcE和cpcF不转入大肠杆菌的情况下,大肠杆菌内只有0.2%的CpcA-PCB产生。以上研究为进一步在大肠杆菌内合成天然的藻蓝蛋白奠定了基础。     

Purification and characteristics of a low-molecular-weight peptide possessing oxidative capacity for phenol from Phanerochaete chrysosporium

A new low-molecular-weight peptide with phenol oxidase activity, named Pc factor, was isolated and purified from liquid culture of a white-rot basidiomycete Phanerochaete chrysosporium. Its molecular weight was about 600 Da estimated by gel-filtration. Three amino acids Glu, Gly and Val were detected in hydrolysate. Absorption peaks corresponding to amino acids and peptide were observed by UV and IR spectra analysis. And the signal of Cα of amino acid was also detected by ¹³C-NMR method. Pc factor had high thermostability and remained active in weakly alkalescent pH range. It could chelate Fe³⁺ and reduce it to Fe²⁺, but no hydroxyl radical HO▪ could be detected during the reaction process. It could oxidize phenolic lignin-model compounds such as 2,6-dimethoxyphenol (2,6-DMP), 2,2¢-azinobis (3-ethylbenzathiazoline-6-sulfinic acid) (ABTS) and syringaldazine in the absence of Mn²⁺ and H₂O₂. These characteristics differed greatly from those of manganese peroxi-dases. The oxidative catalysis of Pc factor can be enhanced by certain metal ions such as Cu²⁺ and Mn²⁺ etc., and O2 molecule was necessary for this reaction. In summary, Pc factor may function as an electron carrier in this novel oxidation-reduction system.     

Cloning, expression and function of phosphate transporter encoded gene in Oryza sativa L.

OsPT6:1, a phosphate transporter encoding gene from the leaf samples of Oryza sativa, was identified through PCR with specifically designed primers. The phylogenetic analysis and the conserved amino acid residue site detection suggested OsPT6:1 a possible high-affinity phosphate transporter encoding gene. In situ hybridization and RT-PCR demonstrated the expression of OsPT6:1 in both roots and leaves. The peak expression signal was observed in mesophyll cells under low phosphorus (P) induction. A homologous recombination study indicated that OsPT6:1 can enhance the Pi uptake efficiency of Pichia pastoris. At the meantime, the introduction of OsPT6:1 was able to complement the Pi uptake function of yeast cells with high-affinity phosphate transporters deficient. Those results substantiated our contention that OsPT6:1 encoded a high-affinity phosphate transporter of Oryza sativa. These authors contributed equally to this work.