Isolation and characterization of a new heterotrophic nitrifying Bacillus sp. strain

Objective To characterize the heterotrophic nitrifying bacteria. Methods The bacteria were isolated from membrane bioreactor for treating synthetic wastewater using the method newly introduced in this study. Fluorescence in situ hybridization （FISH） was used to validate the nonexistence of autotrophic ammonia oxidizers and nitrite oxidizers. Batch tests were carried out to investigate the capability of heterotrophic nitrification by the pure culture. Phylogenetic analysis of the pure culture was performed. Results A heterotrophic nitrifier, named Bacillus sp. LY, was newly isolated from the membrane bioreactor system in which the efficiency of TN removal was up to 80%. After 24-day, incubation, the removal efficiency of COD by Bacillus sp. LY was 71.7 %. The ammonium nitrogen removal rate after assimilation nearly ceased by Bacillus sp. LY was 74.7% The phylogenetic tree of Bacillus sp. LY and the neighbouring nitrifiers were given. Conclusions The batch test results indicate that Bacillus sp. LY can utilize the organic carbon as the source of assimilation when it grows on glucose and ammonium chloride medium accompanying the formation of oxidized-nitrogen. It also can denitrify nitrate while nitrifying. Bacillus sp. LY may become a new bacterial resource for heterotrophic nitrification and play a bioremediation role in nutrient removal.     

In vitro evaluation of the compatibility of a novel collagen-heparan sulfate biological scaffold with olfactory ensheathing cells

Background Stroke and traumatic injury to the nerve system may trigger axonal destruction and the formation of scar tissue, cystic cavitations and physical gaps. Olfactory ensheathing cells （OECs） can secrete neurotrophic factors to promote neurite growth and thus act as a prime candidate for autologous transplantation. Biological scaffolds can provide a robust delivery vehicle to injured nerve tissue for neural cell transplantation strategies, owing to the porous three-dimensional structures （3D）. So transplantation of the purposeful cells seeded scaffolds may be a promising method for nerve tissue repair. This study aimed to evaluate the compatibility of a novel collagen-heparan sulfate biological scaffold with olfactory ensheathing cells in vitro. Methods Collagen-heparan sulfate （CHS） biological scaffolds were made, and then the scaffolds and OECs were co-cultured in vitro. The viability of OECs was tested by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium （MTT） assay at days 1, 3, 5 and 7. Statistical analysis was evaluated by student＇s ttest. Significance was accepted at P 〈0.05. OECs were labeled with carboxyfluorescein diacetate succinimidyl ester （CFSE）, and the CFSE-labeled OECs were seeded into CHS scaffolds. The attachment and growth of OECs in CHS scaffolds were observed and traced directly by fluorescent microscopy and environmental scanning electron microscope （ESEM）. Results CHS biological scaffolds had steady porous 3D structures and no cytotoxicity to OECs （F=-0.14, P=-0.9330）. CHS biological scaffolds were good bridging materials for OECs attachment and proliferation, and they promoted the axonal growth. Conclusion The compatibility of CHS biological scaffolds with OECs is pretty good and CHS biological scaffold is a promising cell carrier for the implantation of OECs in nerve tissue bioengineering.     

Application of decellularized scaffold combined with loaded nanoparticles for heart valve tissue engineering <Emphasis Type="Italic">in vitro</Emphasis>

The purpose of this study was to fabricate decelluarized valve scaffold modified with polyethylene glycol nanoparticles loaded with transforming growth factor-β1(TGF-β1),by which to improve the extracellular matrix microenvironment for heart valve tissue engineering in vitro.Polyethylene glycol nanoparticles were obtained by an emulsion-crosslinking method,and their morphology was observed under a scanning electron microscope.Decelluarized valve scaffolds,prepared by using trypsinase and TritonX-100,were modified with nanoparticles by carbodiimide,and then TGF-β1 was loaded into them by adsorption.The TGF-β1 delivery of the fabricated scaffold was measured by asing enzyme-linked immunosorbent assay.Whether unseeded or reseeded with myofibroblast from rats,the morphologic,biochemical and biomechanical characteristics of hybrid scaffolds were tested and compared with decelluarized scaffolds under the same conditions.The enzyme-linked immunosorbent assay revealed a typical delivery of nanoparticles.The morphologic observations and biological data analysis indicated that fabricated scaffolds possessed advantageous biocompatibility and biomechanical property beyond decelluarized scaffolds.Altogether this study proved that it was feasible to fabricate the hybrid scaffold and effective to improve extracellular matrix microenvironment,which is beneficial for an application in heart valve tissue engineering.     

Bioremediation of quinoline-contaminated soil using bioaugmentation in slurry-phase reactor

Objedive To investigate the possibility of using bioaugmentafion as a strategy for remediating quinoline-contaminated soil. Methods Microorganisms were introduced to the soil to assess the feasibility of enhancing the removal of quinoline from quinoline-contaminated soil. Slurry-phase reactor was used to investigate the bioremediation of quinoline-contaminated soil. HPLC (Hewlett-Packard model 5050 with an UV detector) was used for analysis of quinoline concentration.Results The biodegradafion rate of quinoline was increased through the introduction of Burkholderia pickettii. Quinoline, at a concentration of 1 mg/g soil, could be removed completely within 6 and 8 hours with and without combined effect of indigenous microbes, respectively. Although the indigenous microbes alone had no quinoline-degrading ability, they cooperated with the introduced quinoline-degrader to remove quinoline more quickly than the introduced microbes alone. Bioaugmentaion process was accelerated by the increase of inoculum size and bio-stimulation. The ratio of water to soil in slurry had no significant impact on bioremediation results. Conclusion Bioaugmetation is an effective way for bioremediation ofsoil.     

Analysis of DNA Ploidy, Cell Cycle and Ki67 Antigen in Nasopharyngeal Carcinoma by Flow Cytometry

The expression of DNA ploidy, the cell cycle and Ki67 antigen in nasopharyngeal carcinoma (NPC) were studied and their relationship with the clinical biological behaviors and prognosis of NPC was evaluated. Biopsied specimens of NPC were made into cell suspension. By using cytometric double labeling Ki67 and DNA method, the expression of DNA ploidy, the cell cycle and Ki67 antigen were analyzed. The patients were followed up for about 3 years and the relationship between the above mentioned parameters and the clinical biological behavior and prognosis of NPC were evaluated. Of the 62 cases of NPC, the DNA aneuploid accounted for 29.03 %. The S phase cells accounted for 0 to 54 % in the cell cycle and the positive expression of Ki67 ranged from 0 to 52%. There were 40 cases of LPI (64.5%) including 15 negative cases and 22 cases of HPI (35.5%) respectively. The DNA anneploid content was positively related to the S phase cells. The patients having a low expression of Ki67 or DNA aneuploid in tumor cells were not sensitive to chemotherapy, liable to metastasis to distant organs and had a poor prognosis, while Ki67 showed no correlation with DNA ploidy and the cell cycle. It was suggested that DNA ploidy and Ki67 could be used as an independent and objective marker to evaluate the radiosensitivity and prognosis of NPC.     

Repair of Rabbit Segmental Defects with the Hybrid RP Scaffolds

Objective The objective of this experiment is to observe the effects of hybrid RP scaffolds on repairing segmental bony defects. Methods BMSCs were seeded into the hybrid and original RP scaffolds in order to repairing 15 mm segmental defect in the radius of rabbits. Radiograph, Micro CT and histology were used to evaluate the scaffolds degrading rate and new bone formation. Results The results suggested that the apatite/collagen sponge composite coating could improve the RP scaffolds degrading rate and new bone forming in vivo. Bony union was observed in the hybrid scaffolds group after 1 year post-operation. Conclusion The PLGA/β-TCP scaffolds With apatite/collagen sponge composite coating is promising as a candidate 3D substrate for bone tissue engineering.     

TRAITEMENT DES FRACTURES DE L''''OLECRANE PAR SUTURE PERCUTANEE

The authors devised a method of percutaneous suture for treating fracture of olecranon. There are two operative technics for percutaneous suture: one is the suture through two skin holes and another the suture through four skin holes. 40 cases of fracture of olecranon were resorted to the method of percutaneous suture. Suture with steel wire through two skin holes was used in 3 cases and suture with steel wire through four skin holes in 37 cases. Most of the fractures had satisfactory reduction and all the fractures healed well. 33 cases had been followed for more than one year, the late results were excellent in 20, good in 8, fair in 4 and poor in 1. The operative technic of the percutaneous suture is simple and less traumatic to the local tissues. The late functional recovery is not inferior to that of open reduction with internal fixation.     

Laparoscopic radical cystectomy with orthotopic ileal neobladder in the female: report of 14 cases

Background Bladder carcinoma is the most common malignant urological tumor in China. We present our preliminary experience and results of laparoscopic radical cystectomy （LRC） with orthotopic ileal neobladder in female patients with bladder carcinoma.
Methods From February 2003 to February 2008, 14 female patients with bladder carcinoma underwent LRC with orthotopic ileal neobladder. Nine of these patients underwent hysterectomy and ovariectomy, and the other 5 had preservation of the uterus and ovarian appendage. Standard bilateral pelvic lymphadenectomy was followed by radical cystectomy that was completed laparoscopically with hysterectomy and ovariectomy when needed. The tumor was removed by a 4-5 cm lower midline abdominal incision, followed by the construction of ileal neobladder and the extracorporeal anastomosis of ureter-neobladder. The neobladder was anastomosed to the urethral stump under a laparoscope.
Results The mean operative time and blood loss in the 14 patients were 350.2 minutes and 349.8 ml, respectively. Postoperative complications included uretero-pouch anastomotic stricture in 1 patient and pouch-vaginal fistula in 1 patient. Follow-up time of all patients ranged from 3 to 60 months, and 12 patients were followed up for more than 6 months and achieved micturition in half a year. One patient had occasional day-time urinary incontinence and 2 had night-time incontinence. Two patients who had undergone hystectomy and ovariectomy had voiding difficulties after one year, which was treated by intermittent self-catheterization. The mean volume of the neobladder and the residual urine were 333.6 ml and 31.2 ml, respectively. Surgical margins were tumor free for all patients. One patient had bone metastasis and died 11 months after the operation.
Conclusions LRC with orthotopic ileal neobladder in female patients is a technically feasible, safe and mini-invasive procedure with a low morbidity and acceptable neobladder function. Long-term follow-up is required to confirm the neobladder func     

Deep inferior epigastric perforator flap for breast reconstruction: experience with 43 flaps

Background In the past decade, there has been increasing breast reconstructions after mastectomy. The ideal material for reconstruction of a breast is fat and skin. The transverse rectus abdominis myocutaneous (TRAM) flap has been the gold standard for breast reconstruction until recently. Abdominal wall function is a major concern for plastic surgeons in breast reconstruction with TRAM flaps. The deep inferior epigastric perforator (DIEP) free flap spares the whole rectus abdominis muscle, includes skin and fat only, and therefore preserves adequate abdominal wall competence. The aim of this study was to summarize our experience in breast reconstruction with DIEP flap.Methods Between March 2000 and August 2005, a total of 43 breast reconstructions were performed on 40 patients by our surgeons using DIEP flap (3 patients had bilateral procedures), 14 of them were immediate surgeries and 26 were delayed. Abdominal function, satisfaction with the donor site and reconstructed breast, and the sensation recovery was assessed respectively during follow-up. Results The mean age of the patients was 38.6 years (range, 28－50). The size of the flaps was 11 cm×26 cm in average (height 10－12 cm, width 15－33 cm). The mean length of the vascular pedicles was 9.3 cm (range, 7－12). The patients were followed up for a mean of 16 months (range, 6－30 months). During the follow-up, 2 (5%) patients had total flap loss, 2 (5%) had partial necrosis, 4 (9%) had wound edge necrosis in the abdomen, and 1 had axillary seroma. None of the patients had hernia, and all of them were able to resume their daily activities after the operation. Patient satisfaction with the reconstructed breast rated high, 95% of the patients achieved spontaneous return of sensation in the reconstructed breast, but none of them had a sensation equivalent or approximate to the normal. Conclusions The DIEP flap has the same benefits as the TRAM flap without destroying the continuity of the rectus muscle. It can reduce donor-site morbidity and provide an aesthetic refinement in breast reconstruction.     

Hepatitis C viral infection in a Chinese hemodialysis unit

Background The prevalence of hepatitis C virus （HCV） infection among maintenance hemodialysis （MHD） patients varies among countries and among dialysis units within a single country. The present study aimed to investigate the prevalence and characteristics of HCV infection in MHD patients in a Chinese hemodialysis unit.Methods One hundred and ninety-two patients on MHD for an average of （86.1±30.0） months （range 6-181 months） were enrolled in this cross-sectional study. HCV antibody and HCV-RNA were measured in these MHD patients before hemodialysis by enzyme-linked immunosorbent assay （ELISA） and polymerase chain reaction （PCR） methods.According to the result, all the patients were then divided into two groups： GroupⅠwas positive for HCV antibody and/or HCV-RNA （n=32）, and Group Ⅱ was negative for HCV antibody and HCV-RNA （n=160）. The following information was obtained for all the patients： socio-demographic data, history of blood transfusions and kidney transplantation, and some laboratory values. The MHD patients who were positive for HCV antibody and/or HCV-RNA were followed for more than three years. The disease activities were graded into ＂asymptomatic＂ if alanine aminotransferase （ALT） was less than 40 U/L,＂low activities＂ if ALT was 40-79 U/L, and ＂high activities＂ if ALT was equal to or above 80 U/L.Results The prevalence of HCV infection in MHD patients in our dialysis unit in May 2009 was 16.7, which was significantly higher than in general population （3.2%）. Among the 32 MHD patients with HCV positive, 20 patients were positive for HCV antibody but negative for HCV-RNA, eight patients were positive both for HCV antibody and HCV-RNA,four patients were negative for HCV antibody but positive for HCV-RNA. Eleven patients had a history of kidney transplantation and 12 had a history of blood transfusion, which were significantly more than among the MHD patients without HCV. Thirty of the 32 MHD patients were asymptomatic. There were no significant differences in age, aspartate aminotransferase （AST）, ALT, or between HCV-RNA positive group and HCV-RNA negative group. But the dialysis duration in the HCV-RNA positive group was significantly longer than that in the HCV-RNA negative group. All the 20HCV-RNA negative patients were asymptomatic. Two of the 12 HCV-RNA positive patients had low activity. None of the 32 cases with HCV positive markers had cirrhosis.Conclusions A high prevalence of HCV infection in MHD patients is related to blood transfusion and kidney transplantation. Occult HCV infection is present in MHD patients. Chronic hepatitis C among MHD patients is mild in disease activity, and is not progressive, perhaps due to immunological abnormalities in these patients.     

生物质油精制前后燃烧性能比较

对生物质喷动流化床快速裂解油进行催化裂解精制，在氧气气氛，不同升温速率下对精制前后的生物质油和精制油进行TG—DTA分析，对生物质油精制前后的燃烧性能和动力学进行了分析和比较。结果表明：精制后比精制前挥发所需能量降低了10．02kJ／mol；燃烧活化能由原来的173．64kJ／mol降低到80．95kJ／mol，这说明精制后的精制油大大降低了燃烧所需的活化能，提高了油的可燃性，使得生物质油更容易燃烧。     

酚醛树脂对高软化点沥青的发泡行为及生物挂膜性能的影响

以高软化点沥青为原料,采用自发泡法制备泡沫炭,将其用作生物污水处理固菌载体材料,并通过添加适量的酚醛树脂以提高泡沫炭的开孔率,进而提高其生物挂膜量。研究结果表明：当在高软化点沥青中添加酚醛树脂的质量分数为30%时,所制泡沫炭的开孔率高达100%,生物挂膜量（质量分数）达5.4%;当酚醛树脂的添加质量分数为40%时,所制泡沫炭的压缩强度达5.2 MPa,但其开孔率较低,孔结构的均一性较差。     

一株异养硝化细菌USTB05的培养和活性研究

目的在成功筛选出异养硝化细菌USTB05的基础上,本文重点在USTB05的发酵培养和活性进行了研究。结果表明,采用乙醇和氨氮分别作为碳源和氮源,发酵培养1天可以获得OD680nm38.0的高异养硝化菌生物量。培养出的菌细胞去除氨氮活性高达50mg/g/h,产生亚硝酸氮的活性达到9.6mg/g/h,在高效去除氨氮方面具有重要意义和应用价值。     

生物质材料对水体中染料和其他有机污染物的吸附

大量研究表明：纤维素基生物质、甲壳素和微生物对水体中染料的吸附容量低于商品活性碳对染料的吸附容量;虽然壳聚糖对一些阴离子型染料有相当大的吸附容量,但由于其性能不稳定,因此难以获得大规模工业应用。关于生物质对其他有机污染物吸附性能的研究报道相对较少,说明这方面的研究有待于进一步深入和拓展。废弃皮胶原是一类来源极其丰富的生物质,近年来的研究发现：基于皮胶原研制的新型吸附剂对水体中的阴离子型染料和有机酸能有效去除,有可能在染料和有机废水处理方面得到应用。     

发酵类生物反应器参数在线监控技术

概述了发酵类生物反应器及其过程参数的控制方法、在线监控技术,拟为目前发酵类生物反应过程参数的在线监控技术的深入研究提供思路。     

甘草根系呼吸代谢与生物量积累的相关性分析

[目的]研究甘草根系呼吸代谢与生物量积累的关联关系,为探索生理生化反应与目标收获量的可能影响机制奠定研究基础。[方法]溶氧法测定甘草根系呼吸强度;通过抑制关键酶的活性,测定各个基础生化途径的呼吸强度;采用烘干称质量法测定甘草地上部分和地下部分的生物量;通过灰色关联分析方法考察甘草根系呼吸代谢与生物量的相关关系。[结果]甘草根系以EMP-TCA呼吸途径和PPP呼吸途径为主,两条途径共同作用,9月上旬甘草根系呼吸代谢变化较显著,以EMP呼吸途径占总呼吸的比例最小,PPP呼吸途径占的比例最大,TCA的变化总体较小。TCA途径的呼吸强度与甘草地上部分生物量积累的关联度较大,关联系数为0.828 2,其次为PPP途径,而EMP途径的关联性较小(0.500)。3个基础生化途径与地下部分生物量积累均具有一定的关联度,但关联系数较小,且他们之间的差别不大。[结论]三羧酸循环、磷酸戊糖途径与甘草地上部分生物量积累的关联度较大,但3个基础生化途径与地下部分生物量积累的关联度差异不大。     

珊瑚人工骨的实验研究

用6只杂交狗对珊瑚人工骨的生物学特性及其在成骨过程中的作用及机制进行了初步探讨，经扫描电镜及能谱分析证明，珊瑚人工骨在成骨过程中具有良好的骨传导性、有加速新骨形成的作用，同时发现由于珊瑚人工骨在成骨过程中吸收降解过快，因而与骨的形成不完全同步，应属于不完全骨修复。     

焦化废水生化出水总氰构成及去除特性

了解总氰的构成对提高焦化废水处理装置的除氰能力意义重大。通过水质分析和研究铁氰络合物的去除特性发现,铁氰络合物对生化出水中总氰的贡献率超过90%,铁氰络合物虽见光易分解,但在缺乏光照的生化反应器中,微生物对其的去除作用主要表现为吸附而非降解。另外,酸性、好氧条件和高分子助凝剂的使用有利于形成铁氰化物沉淀。     

固定床反应器基于改进混合模型的串级推断控制

提出了非绝热式固定床反应器基于改进混合模型的串级非线性推断控制策略。道德提出了邻二甲苯氧化非绝热式固定床反应器基于改进混合模型的推断估计器;然后设计了基于新型非线性自适应控制算法的副控制器和基于程序变增益ＰＩＤ的主控制器,同时设计了新型非线性滤波器以解决该反应器主回路比副回路响应快的问题;最后建立了该固定床反应器基于改进混合模型的串级非线性推断控制系统。仿真结果表明该推断估计器具有良好的静态、动态     

生物质燃料乙醇副产木寡糖的研究

木寡糖是一种新兴的、功能优于其他低聚糖的药物或食品基料。应用缓慢絮凝动力学方法,提取木质纤维素制取燃料乙醇残液中的木寡糖,并用毛细管电色谱法,聚丙烯酰胺凝胶电泳法检测木寡糖质量。结果表明:燃料乙醇副产木寡糖相对分子质量为300~600,纯度可达90%。