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Coal mining leads to ventilation air methane emission, which not only pollutes the environment but also runs counter to "carbon neutral, carbon peaking" in China.This study prepared a sub-nanometer Pd cluster catalyst encapsulated in the Silicalite-1 molecular sieve support by the one-pot hydrothermal method, which has excellent catalytic activity and stability in methane catalytic oxidation reaction.The physical phase composition, pore structure parameters, microscopic morphology, chemical state and the present state of the active component Pd of the catalytic material were characterized by XRD, BET, SEM, XPS and TEM.This study then investigated the effects of active component loading, air velocity, reaction temperature and other conditions on the catalytic performance.The experimental results showed that the one-pot hydrothermal method successfully encapsulate Pd clusters within the pores of Silicalite-1 molecular sieve carriers to prepare highly dispersed sub-nanometer Pd cluster catalysts; the catalytic performance first increases and then decreases with the increase of Pd loading.This was due to the agglomeration effect between Pd atoms, resulting in the encapsulation of some Pd atoms and reducing the contact area between the active component and the reactants; in addition, using Silicalite-1 molecular sieve as a carrier can promote the conversion of active site skeletal oxygen to surface hydroxyl groups, which contributes to the catalytic oxidation of methane.The catalyst in this study excels existing methane catalytic process for its high catalytic activity, simple preparation, and low processing cost.

Objective To understand the current prevalence of cervical and breast cancers and their influencing factors in women aged 30-64 years in Xiangyang city. Methods A questionnaire survey was conducted to collect information of demographic characteristics, past medical history, family tumor history, menstrual and reproductive history and the prevalence of common gynecological diseases among married women aged 30-64 years in Xiangyang. Cervical cancer screening was performed primarily by high-risk HPV typing detection, followed by Thinprep cytologic test, colposcopy and pathological examination. Breast cancer screening was performed through visual inspection, palpation and color Doppler ultrasonography, followed by X-ray mammography and pathological examination. Results A total of 318067 women participated in the screening in 2017, among which 91143(28.66%) cases had non-HPV genital tract infection and 91143(28.66%) cases had benign uterine disease; 826(259.69/105) cases had cervical precancerous lesions, including 385 cases of CINⅡ, 425 cases of CINⅢ and 16 cases of adenocarcinoma in situ; 79(24.84/105) cases were cervical cancer, including 18 cases of microinvasive carcinoma and 61 cases of invasive cancer; 44097(13.86%) cases had benign breast disease and 80(25.27/105) cases were breast cancer. Multivariate regression analysis indicated that age, family history of cervical cancer, multiple pregnancies, delayed menopause and reproductive tract infection may be risk factors for cervical cancer, while age, high level of education and family history may be risk factors for breast cancer. Conclusion The incidence of cervical and breast cancers in Xiangyang city is at a moderate level. Regular screening and active control of high-risk factors are of great significance to the prevention and treatment of cervical and breast cancers.

Objective To investigate the effect of different concentrations of fluoride on the expression of transforming growth factor-β1 (TGF-β1), and explore the mechanism of dental fluorosis. Methods 40 Wistar rats were randomly divided into three groups, and supplied with low dose F-(60 mg·L-1, 13 rats), high dose F-(120 mg·L-1, 13 rats) and distilled water (control group, 14 rats) respectively. After 10 weeks, hematoxylin-eosin (HE) and immunohisto- chemistry staining were used to observe the changes of the ameloblasts and the expression of TGF-β1 in rat incisors. Results The fluoride groups showed typical symptoms of dental fluorosis. The surfaces of the rat teeth fed with fluoride appeared chalky color and cross striation on the enamel surface. The HE staining showed that the morphous of ameloblast were disarranged and cellular derangement, even appeared vacuolar change. TGF-β1 were expressed both in ameloblast of the secretory and maturation stage, and also in stellate reticulum and stratum intermedium. The expression of TGF-β1 in rat's ameloblasts in experiment group was significantly lower than that in the control group (P<0.0l), yet low dose group and high dose group still had no significant difference(P>0.05). Conclusion By inhibiting the expression of TGF-β1 in ameloblast, fluoride interferes the normal signal transduction between epithelial and mesenchymal, and affect the differentiation and development of enamel, so leading to the occurrence of dental fluorosis. [ABSTRACT FROM AUTHOR]

Objective To assess the curative effect of microscopic anterior cervical approach in cervical spondylotic diseases. Methods A total of 75 patients were selected, who underwent microscopic subtotal anterior cervical decompression and titanium mesh to fusion fixation or microscopic decompression of resection of the cervical intervertebral disc and cage implant fixation in Tianjin People's Hospital since October 2011 to October 2012. The Cervical vertebra gap involved 1 level in 41 cases, 2 levels in 30 cases and 3 levels in 4 cases. Patients followed up regularly after operation. The nerve function was assessed using Japanese orthopaedic association scoring system (JOA) function was calculated to examine the improvement rate and to assess the curative effect of microscopic anterior cervical approach. Results All patients were followed up. The nerve function recovery was excellent in 44 cases, was well in 25 cases, was general in 6 cases, and the excellent and well recovery rate was 92%. There was no significant difference between excellent recovery rate and well recovery rate. There were significant differences in values of each cervical levels between before and after surgery in the last follow-up of patients (P < 0.05). Conclusion Microscopic operative treatment for cervical spondylotic is safe and effective, with less trauma and bleeding. After surgical decompression, the recovery is rapid in patients with early ambulation. [ABSTRACT FROM AUTHOR]

Sterols are a class of cyclopentano-perhydrophenanthrene derivatives widely present in living organisms. Sterols are important components of cell membranes. In addition, they also have important physiological and pharmacological activities. With the development of synthetic biology and metabolic engineering technology, yeast cells are increasingly used for the heterologous synthesis of sterols in recent years. Nevertheless, since sterols are hydrophobic macromolecules, they tend to accumulate in the membrane fraction of yeast cells and consequently trigger cytotoxicity, which hampers the further improvement of sterols yield. Therefore, revealing the mechanism of sterol transport in yeast, especially understanding the working principle of sterol transporters, is vital for designing strategies to relieve the toxicity of sterol accumulation and increasing sterol yield in yeast cell factories. In yeast, sterols are mainly transported through protein-mediated non-vesicular transport mechanisms. This review summarizes five types of sterol transport-related proteins that have been reported in yeast, namely OSBP/ORPs family proteins, LAM family proteins, ABC transport family proteins, CAP superfamily proteins, and NPC-like sterol transport proteins. These transporters play important roles in intracellular sterol gradient distribution and homeostasis maintenance. In addition, we also review the current status of practical applications of sterol transport proteins in yeast cell factories.

Plant natural products are one of the main sources of small molecule drugs, nutraceuticals, cosmetics and fragrances, and play an important role in economy development. At present, the way of obtaining plant natural products mainly depends on direct extraction from plants, which is farm land occupying and time consuming. The contents of active ingredients in plants are usually low, and thus the production cost is high. By elucidating the biosynthetic pathways and reconstructing the pathways in microbial cells, plant natural products can be produced by fermentation using renewable raw materials. Microbial biosynthesis provides a new route for the supply of plant natural products. This review summarizes the research progress of microbial synthesis of terpenoids, flavonoids, phenylpropanoids and other important natural products of plants in Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences. Current research challenges and future prospects are also briefly discussed.

Utilization of carbon dioxide (CO 2 ) is a huge challenge for global sustainable development. Biological carbon fixation occurs in nature, but the low energy efficiency and slow speed hamper its commercialization. Physical-chemical carbon fixation is efficient, but relies on high energy consumption and often generates unwanted by-products. Combining the advantages of biological, physical and chemical technologies for efficient utilization of CO 2 remains to be an urgent scientific and technological challenge to be addressed. Here, based on the development of Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences in the past decade, we summarize the important progress in the design and construction of functional parts, pathways and systems for artificial bioconversion of carbon dioxide, including the breakthrough on the artificial synthesis of starch from CO 2 . Moreover, we prospect how to further develop the technologies for artificial bioconversion of carbon dioxide. These progress and perspectives provide new insight for achieving the goal of "carbon peaking and carbon neutrality".

Traditionally, amino acids are produced mainly by chemical synthesis or aerobic fermentation. Compared to chemical synthesis, production of amino acids by microbial fermentation directly uses renewable resources as feedstock and this reduces the dependence on petroleum-based compounds and decreases pollutants generation and toxic substrates usage. Fermentation under aerobic conditions has been used widely for its fast growth and high titers. However, a large amount of carbon is used for cell growth and this results in high biomass but low yield of target chemicals. Unlike the long history of aerobic fermentation, the commercial production of amino acids by anaerobic fermentation is realized only in recent years. It has several advantages such as simpler operation, no need for oxygen supply, and high yield close to the theoretical maximum value. L-alanine is the first amino acid commercially produced by anaerobic fermentation. In this article, we summarize the key technology for anaerobic fermentative production of L-alanine and its commercialization. As it is shown to be low-cost, high-efficiency, and environmental-friendly, anaerobic fermentation is expected to be widely used in industrial process and brings greater economic values and social benefits in the future.

Plant biomass represents a vast resource of carbon. In China, it is estimated that 1 billion tons of biomass is available each year. The conversion of these biomass resources into bioethanol or other bio-based chemicals, if fully commercialized, may reduce at least 200 million tons of crude oil import. Therefore, bioethanol and bulk chemicals are the core components of the biomanufacturing using plant biomass as carbon sources. Since the foundation of Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences (TIB, CAS), we have proposed a strategy of "two replacements and one upgrade". Utilizing renewable carbon resources instead of non-renewable petrochemical resources to produce bulk chemicals is included in our strategy. It is a long-term effort for TIB to develop plant biomass biomanufacturing to produce renewable chemicals. Continuous and systematic research was carried out in these two fields, and significant progress has been made in the past 10 years since the foundation of TIB. Here we review the progress of TIB in this field, mainly focusing on fungal system, including the mechanism of cellulose degradation by filamentous fungi and the strategy of consolidated bioprocessing of biomass. Based on this, malic acid, fuel ethanol and other bulk chemicals were produced through one-step conversion of biomass. Besides, the commercial processes for production of bulk chemicals such as succinic and lactic acid from renewable carbon resources, which were developed by TIB, were also be discussed. These examples clearly demonstrated that bulk chemicals can be obtained from biomass instead of from petroleum. Research on plant biomass biotransformation and renewable chemicals production in TIB has provided an alternative route for the development of low-carbon bioeconomy in China, and will contribute to the goal of carbon neutralization of China.

Precise and efficient manipulation of gene expression or rewriting genome sequence is the research hotspots of genome editing, and it is also the core enabling technology contributing to the rapid development of industrial biotechnology. Genome editing technology has experienced three stages of development, from zinc finger nuclease (ZFNs), to transcription activator like effector nuclease (TALEN) and Cas nuclease. Currently, vigorous development of CRISPR/Cas has enabled researchers establish a series of first-generation and second-generation Cas-based genome editing technologies. This contributed to the establishment and optimization for prokaryotic chassis such as Escherichia coli or eukaryotic chassis such as Saccharomyces cerevisiae . This paper summarizes the current development and application of industrial biotechnology using conventional chassis cells, and prospects future development trend with the aim to facilitate researchers to optimize industrial biotechnology and its potential applications.

As an important model industrial microorganism, Escherichia coli has been widely used in pharmaceutical, chemical industry and agriculture. In the past 30 years, a variety of new strategies and techniques, including artificial intelligence, gene editing, metabolic pathway assembly, and dynamic regulation have been used to design, construct, and optimize E. coli cell factories, which remarkably improved the efficiency for biotechnological production of chemicals. In this review, three key aspects for constructing E. coli cell factories, including pathway design, pathway assembly and regulation, and optimization of global cellular performance, are summarized. The technologies that have played important roles in metabolic engineering of E. coli, as well as their future applications, are discussed.

Objective: Based on the accelerometer, the validity of the international physical activity questionnaire long version(IPAQ-L) and Bouchard diary were evaluated to measure the daily physical activity of Chinese adults aged 18-59 years old., Methods: A total of 200 Chinese adults were recruited in Yinzhou District of Ningbo City in 2019, including 78 males and 122 females, the three age groups 18-29, 30-49, 50 and above accounted for 19. 5%, 61. 5% and 18. 0%, respectively. The volunteers wore Actigraph WGT3 x-BT three-dimensional accelerometer for 3 days, and completed the 3 consecutive days& apos; Bouchard diary and the IPAQ-L. The physical activity energy expenditure(PAEE), sedentary inactivity time, light physical activity time(LPA) and moderate-to-vigorous physical activity time(MVPA) measured by the three tools were estimated respectively. Spearman analysis was used to analyze the correlation, the Friedman test and the Bland-Altman plot were used to test the homogeneity of the three method., Results: 196 volunteers were included in this study. The correlation coefficients of PAEE between IPAQ and diary and accelerometer were 0. 32 and 0. 58, respectively, the correlation coefficients of sedentary behavior were 0. 17, 0. 25, and LPA time was 0. 33, and the estimated IPAQ for MVPA time better than diary. The difference test result showed that, except for IPAQ in the measurement of MVPA, there was no statistical difference from the accelerometer measurement result(P=0. 684), and the difference between other estimated values and the accelerometer measurement result was statistically significant(P& lt; 0. 01), Bland-Altman plot result showed that the diary and IPAQ had good consistency in the measurement of PAEE and IPAQ in the estimation of MVPA time, but there was an overestimation in PAEE. In addition, IPAQ had poor validity in measuring sedentary behavior and LPA., Conclusion: IPAQ and Bouchard diary have better validity in evaluating PAEE, and the diary is better than IPAQ. IPAQ has better validity in evaluating MVPA time, but has poor validity in estimating sedentary behavior and LPA time.

The introduction of the mevalonate pathway (MVA pathway) in recombinant Escherichia coli can improve the synthesis of terpenoids. But the imbalance expression of MVA pathway genes and accumulation of intermediates inhibit cell growth and terpenoids production. In this study, each gene of MVA pathway and key genes of lycopene synthesis pathway were cloned in plasmid to express in the recombinant E. coli LYC103 with optimizing the expression of the key genes of the 2-methyl-D-erythritol-4-phosphate pathway (MEP pathway), chromosome recombinant MVA pathway and the lycopene synthesis pathway. The results showed that the overexpression of ispA, crtE, mvaK1, idi and mvaD genes did not affect the cell growth, while lycopene production increased by 13.5%, 16.5%, 17.95%, 33.7% and 61.1% respectively, indicating that these genes may be the rate-limiting steps for the synthesis of lycopene. mvaK1, mvaK2, mvaD of MVA pathway were the rate-limiting steps and were in an operon. The mvaK1, mvaK2, mvaD operon was regulated by mRS (mRNA stabilizing region) library in front of mvaK1, obtaining strain LYC104. Lycopene yield of LYC104 was doubled and cell growth was increased by 32% compared with the control strain LYC103. CRISPR-cas9 technology was used to integrate idi into chromosome at lacZ site to obtain LYC105 strain. Cell growth of LYC105 was increased by 147% and lycopene yield was increased by 2.28 times compared with that of LYC103. In this study, each gene of lycopene synthesis pathway was expressed in plasmid to certify the rate-limiting gene based on the complete MVA pathway on the chromosome. Then the rate-limiting gene was integrated in chromosome with homologous recombination to release the rate-limiting, which providing a new strategy for the construction of high-yield strains for metabolic engineering.

Objective: To elucidate the relationship between preoperative C 7 slope (C 7 S) and sagittal parameters in anterior cervical discectomy with fusion (ACDF) by imaging., Methods: A retrospective analysis of 54 patients (24 males and 30 females) with ACDF for cervical spondylosis between January 2012 and January 2017 was performed. The age ranged from 23 to 71 years (mean, 46.6 years). There were 29 cases of cervical spondylotic radiculopathy and 25 cases of cervical spondylotic myelopathy. The disease duration ranged from 3 to 48 months, with an average of 16.8 months. In the 55 patients, 44 were single-segment ACDF and 10 were double-segment ACDF. Sagittal parameters of cervical spine were measured on cervical X-ray films before operation and at last follow-up, including C 2-7 Cobb angle, C 2-7 sagittal vertical axis (C 2-7 SVA), C 7 S, and segment Cobb angle (SCobb), and the changes of C 2-7 Cobb angle (the difference between the last follow-up and the preoperative angle) were calculated. Pearson correlation was used to analyze the correlation between the parameters before operation and at last follow-up. According to the preoperative median value of C 7 S (15°), the patients were divided into group A (C 7 S<15°) and group B (C 7 S≥15°). The sagittal parameters before and after operation were compared between the two groups., Results: All the 54 patients were followed up 6-45 months (mean, 15.5 months). At last follow-up, C 7 S, C 2-7 Cobb angle, C 2-7 SVA, and SCobb angle were significantly improved when compared with preoperative values ( P <0.05). Correlation analysis showed that the preoperative C 7 S and SCobb angles were significantly correlated with C 2-7 Cobb angle and C 2-7 SVA ( P <0.05), but there was no significant correlation between C 7 S and SCobb angle ( r =0.049, P =0.724). There was a significant correlation between C 7 S, C 2-7 Cobb angle, and SCobb angle at last follow-up ( P <0.05), but there was no significant correlation between C 7 S and SCobb angles and C 2-7 SVA ( P >0.05). According to the median value of preoperative C 7 S, 28 patients in group A had C 7 S of (11.82±3.60)°, while 26 patients in group B had C 7 S of (20.77±4.09)°. There was no significant difference in gender and age between the two groups ( P >0.05). The preoperative C 2-7 Cobb angle and C 2-7 SVA in group A were significantly lower than those in group B ( P <0.05). There was no significant difference between preoperative SCobb angle and group B ( t =0.234, P =0.816). There were no significant differences in C 2-7 Cobb angle, C 2-7 SVA, and SCobb angle between group A and group B at last follow-up ( P >0.05). However, the change of C 2-7 Cobb angle in group A was significantly higher than that in group B ( t =2.321, P =0.024)., Conclusion: Preoperative C 7 S≥15° group has more physiological lordosis before operation, but its postoperative cervical curvature changes less, while ACDF is more conducive to correct the preoperative C 7 S<15 ° cervical curvature.

Isoprenoids are all derived from two five-carbon building blocks called isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), which are synthesized either by the mevalonate (MVA) pathway or 2-C-methyld-D-erythritol-4-phosphate (MEP) pathway. In this study, the MVA pathway genes were integrated into the chromosome of LYC101, in which the expression of key genes in the MEP synthesis pathway and lycopene synthesis pathway were optimized by artificial regulatory parts, to further improve the production of isoprenoids in Escherichia coli. The plasmids pALV23 and pALV145 were screened from a plasmid library that constructed by using the RBS library to link the genes of the MVA pathway, which greatly increased the production of β-carotene. The effects of plasmids pALV23 and pALV145 on the lycopene production in low and high lycopene production strain, LYC001 and LYC101, were compared, respectively. The production of lycopene was increased by plasmids pALV23 and pALV145 in both strains. In high lycopene production strain LYC101, pALV23 produced more lycopene than pALV145. Then, the MVA gene together of promoter of pALV23 was integrated into the chromosome of LYC101 at poxB site using method of homologous recombination helped by CRISPR-Cas9 system, resulted in genetically stable strain, LYC102. The yield of lycopene of LYC102 was 40.9 mg/g DCW, 1.19-folds higher than that of LYC101, and 20% more than that of LYC101 with pALV23. Simultaneous expression of MVA pathway and MEP pathway in recombinant E. coli can effectively increase the yield of terpenoids. In this study, a plasmid-free, genetically stable, high-yielding lycopene strain was constructed, which could be used for industrialization. Also, the platform strain can be used for the synthesis of other terpenoids.

Objective: s To investigate the distributions of single nucleotide polymorphisms (SNPs) of tissue factor (TF) and its inhibitor tissue factor pathway inhibitor (TFPI) and analyze the association of the SNPs with venous thromboembolism (VTE) in lung cancer patients. Methods: Between October 2009 and August 2013, a total of 152 hospitalized patients with newly diagnosed primary non-small cell lung cancer were enrolled from Beijing Chao Yang Hospital. Among them [male 105 cases, female 47 cases, with an age of (62.4±13.2) years old], 40 cases were lung cancer patients with VTE, 112 cases were lung cancer patients without VTE. In the same period, 79 healthy controls were included from the physical examination center. All patients' blood specimens were collected and their DNA was isolated. The selected SNPs were TF+ 5466A/G, TFPI-287T/C and TFPI-33T/C and they were investigated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) followed by validation of DNA sequence analysis. Results: Allelic frequencies of TF+ 5466G, TFPI-287C and TFPI-33C were 2.5%, 33.8% and 8.8%, respectively. There was no significant difference among the three groups in genotype or allele frequency distributions of TF+ 5466A/G, TFPI-287T/C and TFPI-33T/C polymorphisms (all P >0.05). There was no difference from different genders and ages in allele or genotype frequency distributions of TF+ 5466A/G, TFPI-287T/C and TFPI-33T/C polymorphisms among the three groups (all P >0.05). Meanwhile, the frequency distributions of genotype and allele of the three SNPs were not associated with lung cancer patients with VTE (all P >0.05). Still, no relationship was found between genotype or allele frequency distributions of the three SNPs with prognosis of lung cancer patients with VTE. Conclusion: Genotype alterations in TF+ 5466A/G, TFPI-287T/C and TFPI-33T/C may be unrelated to the occurrence of VTE and the prognosis of lung cancer patients with VTE.

Objective: To investigate whether preoperative T 1 slope (T 1 S) in MRI can predict the changes of cervical curvature after expansive open-door laminoplasty (EOLP) in patients with cervical spondylotic myelopathy, so as to make up for the shortcomings of difficult measurement in X-ray film., Methods: The clinical data of 36 patients with cervical spondylotic myelopathy who underwent EOLP were retrospectively analysed. There were 21 males and 15 females with an average age of 55.8 years (range, 37-73 years) and an average follow-up time of 14.3 months (range, 12-24 months). The preoperative X-ray films at dynamic position, CT, and MRI of cervical spine before operation, and the anteroposterior and lateral X-ray films at last follow-up were taken out to measure the following sagittal parameters. The parameters included C 2 -C 7 Cobb angle and C 2 -C 7 sagittal vertical axis (C 2 -C 7 SVA) in all patients before operation and at last follow-up; preoperative T 1 S were measured in MRI, and the patients were divided into larger T 1 S group (T 1 S>19°, group A) and small T 1 S group (T 1 S≤19°, group B) according to the median of T 1 S, and the preoperative T 1 S, C 2 -C 7 Cobb angle, C 2 -C 7 SVA, and the C 2 -C 7 Cobb angle and C 2 -C 7 SVA at last follow-up, difference in axial distance (the difference of C 2 -C 7 SVA before and after operation), postoperative curvature loss (the difference of C 2 -C 7 Cobb angle before and after operation), the number of patients whose curvature loss was more than 5° after operation, and the number of patients whose kyphosis changed (C 2 -C 7 Cobb angle was less than 0° after operation)., Results: The C 2 -C 7 Cobb angle at last follow-up was significantly decreased when compared with preoperative value ( t =8.000, P =0.000), but there was no significant difference in C 2 -C 7 SVA between pre- and post-operation ( t =-1.842, P =0.074). The preoperative T 1 S was (19.69±3.39)°; there were 17 cases in group A and 19 cases in group B with no significant difference in gender and age between 2 groups ( P >0.05). The preoperative C 2 -C 7 Cobb angle in group B was significantly lower than that in group A ( t =-2.150, P =0.039), while there was no significant difference in preoperative C 2 -C 7 SVA between 2 groups ( t =0.206, P =0.838). At last follow-up, except for the curvature loss after operation in group B was significantly lower than that in group A ( t =-2.723, P =0.010), there was no significant difference in the other indicators between 2 groups ( P >0.05)., Conclusion: Preoperative larger T 1 S (T 1 S>19°) in MRI had a larger preoperative lordosis angle, but more postoperative physiological curvature was lost; preoperative T 1 S in MRI can not predict postoperative curvature loss, but preoperative larger T 1 S may be more prone to kyphosis.

Objective: To analyse the correlation between cervical sagittal parameters of cervical spondylotic myelopathy in different sagittal curvature so as to find out representative cervical sagittal alignment parameters by measuring on MRI., Methods: A retrospective analysis was made on the clinical data of 88 patients with cervical spondylotic myelopathy between July 2015 and January 2016. The C 2 -C 7 Cobb angle, T 1 slope (T 1 S), and C 2 -C 7 sagittal vertical axis (C 2 -C 7 SVA) were measured on T2-weight MRI. According to C 2 -C 7 Cobb angle, the patients were divided into lordosis group (≥10° Cobb angle, 48 cases) and straightened group (0-10° Cobb angle, 40 cases). Intraclass correlation coefficient (ICC) was used for the reliability of measured data, Pearson correlation analysis for correlation between cervical sagittal parameters., Results: ICC was 0.858-0.946, indicating good consistency of measurement parameters. The C 2 -C 7 Cobb angle, T 1 S, and C 2 -C 7 SVA were (5.6±2.4)°, (22.2±6.7)°, and (10.2±5.4) mm in straightened group, and were (20.1±8.2)°, (23.4±8.9)°, and (8.2±4.6) mm in lordosis group respectively. There was no correlation between the 3 parameters in straighten group ( r =0.100, P =0.510 for T 1 S and C 2 -C 7 Cobb angle; r =-0.100, P =0.500 for T 1 S and C 2 -C 7 SVA; r =0.080, P =0.610 for C 2 -C 7 Cobb angle and C 2 -C 7 SVA). There was positive correlation between T 1 S and C 2 -C 7 Cobb angle ( r =0.540, P =0.000), negative correlation between T 1 S and C 2 -C 7 SVA ( r =-0.450, P =0.001), and no correlation between C 2 -C 7 Cobb angle and C 2 -C 7 SVA ( r =-0.003, P =0.980)., Conclusion: For cervical spondylotic myelopathy in patients with cervical lordosis, only T 1 S measurement on MRI can be used as the main parameter to judge the sagittal curvature, but in patients with straightened cervical Cobb angle, measurements of T 1 S, C 2 -C 7 Cobb angle, and C 2 -C 7 SVA should be taken for the comprehensive evaluation of cervical sagittal curvature.

Glycerol is a byproduct during biodiesel production. It is an important feedstock for fermentation due to its low price and high reduced status. Multiple genes of the glycerol utilization pathway were modulated in a previously engineered high β-carotene producing Escherichia coli strain CAR015 to enhance glycerol utilization capability for improving isoprenoids production. The glpR gene, encoding glycerol 3-phosphate repressor, was firstly deleted. The glpFK, glpD and tpiA genes were then modulated by three artificial regulatory parts, M1-37, M1-46 and M1-93, respectively. β-carotene titer reached 64.82 mg/L after modulating glpD with M1-46, which was 4.86 times higher than that of CAR015, and glycerol consumption rate also increased 100%. Modulating tpiA led to a little increase of β-carotene titer, whereas modulating glpFK led to a little decrease of β-carotene titer. This demonstrated that GlpD was a rate-limiting step in glycerol utilization pathway. Q-PCR of glpF, glpK, glpD and tpiA results showed that decrease the transcription level of glpF, glpK, glpD, or decrease the transcription level of tpiA could increase the cell growth and β-carotene production, probably for the decrease of methylglyoxal toxicity. Modulating glpD and tpiA genes in combination resulted in the best strain Gly003, which produced 72.45 mg/L β-carotene with a yield of 18.65 mg/g dry cell weight. The titer was 5.23 and yield 1.99 times of that of the parent strain CAR015. Our work suggested that appropriate activation of glpD and tpiA genes in glycerol utilization pathway could effectively improve β-carotene production. This strategy can be used for production of other terpenoids in E. coli.

Plant-derived natural products (PNPs) have been widely used in pharmaceutical and nutritional fields. So far, the main method to produce PNPs is extracting them from their original plants, however, there remains lots of problems. With the concept of synthetic biology, construction of yeast cell factories for production of PNPs provides an alternative way. In this review, we will focus on PNPs' market and application, research progress for production of artemisinin, research progress for production of terpenes, alkaloids and polyunsaturated fatty acid (PUFAs) and recent technology development to give a brief introduction of construction of yeast cells for production of PNPs.

Objective: To explore the value of actigraphy and oximetry for diagnosing sleep apnea-hypopnea syndrome (SAHS)., Methods: Suspected SAHS subjects were enrolled from sleep center of Peking University People's Hospital between December 2013 and September 2014. Light-out and light-on were simultaneously recorded for polysomnography (PSG), actigraphy and oximetry. Actigraphy was used to correct total sleep time (TST) for oximetry. Oxygen desaturation index (ODI4), namely the times of pulse oxygen saturation (SpO2) drop≥4% per hour, was detected by oximetry. ODIA was used instead of ODI4 with TST corrected by actigraphy. Receiver operating characteristic (ROC) curve was used for evaluating the value of ODI4 and ODIA for diagnosing SAHS and cut-off value was calculated. Paired t-test or signed rank t-test was used for data acquired using actigraphy or oximetry compared with data acquired by PSG. Sensitivity and specificity were calculated using fourfold table. Disease severity of SAHS was classified by apnea-hypopnea index (AHI) detected by PSG. If AHI<5/h, SAHS was not considered. 5-<15/h was classified as mild, 15-<30/h was classified as moderate and AHI≥30/h was classified as severe., Results: Among 213 SAHS subjects, 38 of them were normal, 34 of them were mild, 51 were moderate and 90 were severe. Compared with PSG, actigraphy can correctly estimate TST in non-SAHS (P=0.408) and mild SAHS groups (P=0.949); while in moderate and severe SAHS groups, TSTs detected by actigraphy were shorter than TSTs acquired by PSG ((405±51) vs (419±40) min and (399 ± 62) vs (422 ± 60) min) (both P<0.05). Area under ROC curve (AUC) of ODI4 for diagnosing SAHS was 0.956 using a cut-off value of 5; the AUC of ODIA for diagnosing SAHS was 0.951 with a cut-off value of 5 as well. The sensitivity of ODI4 for mild, moderate and severe SAHS was 80.6%, 66.7% and 58.9% respectively, all with a specificity of 100%. After adjusting TST with actigraphy, the sensitivity of ODIA for mild, moderate and severe SAHS was 84.0%, 73.8 % and 68.9%, with specificity of 94.7%, 100% and 99.2% respectively., Conclusions: Actigraphy can correctly estimate TST in non-SAHS and mild SAHS groups. ODI4 can be used for diagnosing SAHS. After correcting TST by actigraphy, the sensitivity of ODIA is higher.

Objective: To explore the value of pulse oximetry for diagnosing obstructive sleep apnea hypopnea syndrome (OSAHS) and evaluation of the effect of the continuous positive airway pressure (CPAP) therapy., Methods: From January 2013 to March 2014, 244 OSAHS patients admitted to department of respiratory and critical care medicine of the first affiliated hospital of Fujian Medical University and department of respiratory and critical care medicine of People's Hospital of Peking University were recruited. According to apnea-hypopnea index (AHI), all patients were divided into mild, moderate and severe groups. The differences in pulse-associated indicators [nocturnal pulse elevation index (NPEI), namely counts of heart rate (HR) variation >6 bpm/h, average HR and standard deviation of HR] were compared among three groups before and after CPAP therapy. Spearman correlation analysis between pulse-associated indicators and AHI was performed to explore the optimal indicator. Receiver operating characteristic (ROC) curve were conducted and sensitivity and specificity were obtained., Results: NPEI after CPAP treatment were significantly lower than before among all the three groups (mild group 15.4±12.4 vs 19.4±13.3, moderate group 15.4±9.1 vs 24.1±11.9, severe group 21.9±14.8 vs 48.8±20.3, all P<0.05); there were significant correlations of AHI with average HR, standard deviation of HR and NPEI (r=0.334, 0.337 and 0.660, respectively) (all P<0.05); ROC curve showed a NPEI of 30beat per hour had a sensitivity of 68.0% and a specificity of 73.0% in diagnosing OSAHS., Conclusion: Nocturnal oximetry could be a useful tool for screening OSAHS in clinical practice, and the NPEI can evaluate the efficacy of the CPAP therapy.

Coenzyme Q10 (CoQ10) is a lipophilic antioxidant that improves human immunity, delays senility and enhances the vitality of the human body and has wide applications in pharmaceutical and cosmetic industries. Microbial fermentation is a sustainable way to produce CoQ10, and attracts increased interest. In this work, the native CoQ8 synthetic pathway of Escherichia coli was replaced by the CoQ10 synthetic pathway through integrating decaprenyl diphosphate synthase gene (dps) from Rhodobacter sphaeroides into chromosome of E. coli ATCC 8739, followed by deletion of the native octaprenyl diphosphate synthase gene (ispB). The resulting strain GD-14 produced 0.68 mg/L CoQ10 with a yield of 0.54 mg/g DCW. Modulation of dxs and idi genes of the MEP pathway and ubiCA genes in combination led to 2.46-fold increase of CoQ10 production (from 0.54 to 1.87 mg/g DCW). Recruiting glucose facilitator protein of Zymomonas mobilis to replace the native phosphoenolpyruvate: carbohydrate phosphotransferase systems (PTS) further led to a 16% increase of CoQ10 yield. Finally, fed-batch fermentation of the best strain GD-51 was performed, which produced 433 mg/L CoQ10 with a yield of 11.7 mg/g DCW. To the best of our knowledge, this was the highest CoQ10 titer and yield obtained for engineered E. coli.

Objective: To the evaluate chemo-responsiveness in patients with obesity hypoventilation syndrome (OHS) and respiratory failure (RF)., Methods: A total of 14 OHS and RF patients with a mean body mass index (BMI) of (34.3 ± 2.68) kg/m(2) hospitalized between January 2009 to December 2011 were recruited. Lung function test (LFT), polysomnograghy (PSG), arterial blood gases (ABG) before and after voluntary hyperventilation maneuver and respiratory responses to hypoxia (ΔVE/ΔSpO(2)) and hypercapnia (ΔVE/ΔPaCO(2)) were measured. Ten of them received bi-level positive airway pressure (BiPAP) for 1 week and pre and post-treatment ABG were compared., Results: All of them fulfilled the criteria of type II respiratory failure. PSG sleep study indicated a mean sleep apnea hypopnea index of (66.6 ± 30.1) times/h and LFT revealed a predicted FEV(1)/FVC% over 70%, excluding chronic obstruction pulmonary disease. Voluntary hyperventilation maneuver induced significant improvements in PaO(2) (52.5 ± 7.6 vs 81.3 ± 11.1 mmHg (1 mmHg = 0.133 kPa, P = 0.001) and PaCO(2) (50.4 ± 5.3 vs 43.2 ± 1.9 mmHg, P = 0.001). RF was reversed in all patients. As compared with normal controls, all patients had decreased ΔVE/ΔSpO(2) ((-0.11 ± 0.08) vs (-0.38 ± 0.04) L×min(-1)×%SpO(2)(-1), P < 0.001) and ΔVE/ΔPaCO(2) (0.31(0.18, 0.66) vs 1.20 (0.82, 1.50) L×min(-1)×mmHg(-1), P < 0.001). One-week BiPAP therapy induced significant improvement of sleep disordered breathing and daytime ABGs without any change of BMI in 10 patients. And PaCO(2) was normalized in 8/10 patients., Conclusions: OHS patients have sleep disordered breathing and depressed chemo-responsiveness. Voluntary hyperventilation maneuver may reverse the "unwilling breathing" type of RF. Non-invasive ventilation treatment may improve nocturnal sleep apnea and daytime ABG abnormality.

β-carotene has a wide range of application in food, pharmaceutical and cosmetic industries. For microbial production of β-carotene in Saccharomyces cerevisiae, the supply of geranylgeranyl diphosphate (GGPP) was firstly increased in S. cerevisiae BY4742 to obtain strain BY4742-T2 through over-expressing truncated 3-hydroxy-3-methylglutaryl-CoA reductase (tHMGR), which is the major rate-limiting enzyme in the mevalonate (MVA) pathway, and GGPP synthase (GGPS), which is a key enzyme in the diterpenoid synthetic pathway. The β-carotene synthetic genes of Pantoea agglomerans and Xanthophyllomyces dendrorhous were further integrated into strain BY4742-T2 for comparing β-carotene production. Over-expression of tHMGR and GGPS genes led to 26.0-fold increase of β-carotene production. In addition, genes from X. dendrorhous was more efficient than those from P. agglomerans for β-carotene production in S. cerevisiae. Strain BW02 was obtained which produced 1.56 mg/g (dry cell weight) β-carotene, which could be used further for constructing cell factories for β-carotene production.

β-carotene belongs to carotenoids family, widely applied in pharmaceuticals, neutraceuticals, cosmetics and food industries. In this study, three key genes (dxs, idi, and crt operon) within β-carotene synthetic pathway in recombinant Escherichia coli strain CAR005 were modulated with RBS Library to improve β-carotene production. There were 7%, 11% and 17% increase of β-carotene yield respectively after modulating dxs, idi and crt operon genes with RBS Library, demonstrating that modulating gene expression with regulatory parts libraries would have more opportunities to obtain optimal production of target compound. Combined modulation of crt operon, dxs and idi genes led to 35% increase of β-carotene yield compared to parent strain CAR005. The optimal gene expression strength identified in single gene modulation would not be the optimal strength when used in combined modulation. Our study provides a new strategy for improving production of target compound through modulation of gene expression.

Objective: To retrospectively evaluate the clinical evaluation of preoperative lumbar T2 sagittal MRI image in predicting the recurrent lumbar disc herniation (RLDH)., Methods: Between January 2009 and April 2011, 28 patients were diagnosed as recurrent L4-5 disc herniation within 2.5 years after surgery, and 25 of them were included in the study as relapse group. At the same time, selected 25 patients implemented the same surgical methods in the same level as a control group randomly, they were all with good to excellent result and the follow-up time was at least 2.5 years. There was no statistical significance between the two groups in gender, age and body mass index(BMI) (P > 0.05). The lumbar MRI image of two groups of patients before surgery were collected and analyzed, with the disc degeneration grade classified. The χ(2) test was used to analyzed the difference of degeneration between the two groups of patients before surgery. Rank correlation analysis evaluated the correlation between disc degeneration and the period of time from the first operation to the recurrence., Results: In terms of preoperative lumbar disc degeneration, there were 22 cases of low-grade disc degeneration and 3 cases of advanced disc degeneration in the relapse group and 5 cases and 20 cases respectively in the control group. there was significant difference between two groups (χ(2) = 23.27, P < 0.05), low-grade disc degeneration (gradesIand III) was significantly more frequent in the relapse group than in the control group. The patients with low-grade disc degeneration had a higher risk of recurrence, that was the risk of recurrent disc herniation increased by a factor of 4.4 from advanced disc degeneration to low-grade disc degeneration(OR = 4.4, 95%CI:1.983-9.765, P < 0.05). In cases of recurrence, the time interval between primary surgery and the recurrence of the patient with advanced disc degeneration was longer compared with low-grade disc degeneration (r = 0.733, P < 0.05)., Conclusions: Preoperative lumbar MRI image may suggest the possibility of the recurrence lumbar disc herniation.Light disc degeneration is an important risk factor for recurrent disc herniation, and the time interval between primary surgery and the recurrence is positively correlated with severity of disc degeneration.

D-Mannitol has wide applications in food, pharmaceutical, and chemical industries. In this study, we constructed a genetically stable Escherichia coli strain for D-mannitol production by integrating mannitol dehydrogenase (mdh) and fructose permease (fupL) genes of Leuconostoc pseudomesenteroides ATCC 12291 into chromosome of E. coli ATCC 8739 and inactivating other fermentation pathways (including pyruvate formate-lyase, lactate dehydrogenase, fumarate reductase, alcohol dehydrogenase, methylglyoxal synthase and pyruvate oxidase). Using mineral salts medium with glucose and fructose as carbon sources, the engineered strain could produce 1.2 mmol/L D-mannitol after anaerobic fermentation for 6 days. Based on the coupling of cell growth and D-mannitol production, metabolic evolution was used to improve D-mannitol production. After evolution for 80 generations, D-mannitol titer increased 2.6-fold and mannitol dehydrogenase activity increased 2.8-fold. Genetically stable strains constructed in this work could ferment sugars to produce D-mannitol without the addition of antibiotics, inducers and formate, which was favorable for industrial production.

Objective: To evaluate the effectiveness of combined posterior decompression with laminoplasty and anterior decompression with fusion for the treatment of cervical spinal canal stenosis with reverse arch., Methods: Between May 2009 and February 2012, 13 cases of cervical spinal canal stenosis with reverse arch underwent posterior decompression with laminoplasty surgery in prone position and then anterior decompression with fusion surgery in supine position. There were 7 males and 6 females with an average age of 43.5 years (range, 38-62 years) and an average disease duration of 25 months (range, 18-60 months). All the patients had neck axial symptoms and spinal cord compressed symptoms, and lateral computer radiology (CR) of the neck showed reverse arch of cervical vertebrae. Segments of intervertebral disc protrusion included C3-6 in 4 cases, C4-7 in 4 cases, and C3-7 in 5 cases. After operation, anteroposterior and lateral CR was used to observe the cervical curvature change and fixation loosening, MRI to observe the change of the compression on spinal cord, visual analogue scale (VAS) score to evaluate the improvement of axial symptom, and Japanese Orthopaedic Association (JOA) score to assess the nerve function improvement., Results: All incisions healed by first intention. All patients were followed up 9-32 months (mean, 15.4 months). Internal fixator had good position without loosening or breaking and the compression on spinal cord improved significantly after operation. All the patients obtained bony fusion at 6 months after operation. The axial symptoms and the nerve function at last follow-up were improved. VAS score at last follow-up (3.25 +/- 1.54) was significantly lower than that at preoperation (6.55 +/- 1.52) (P < 0.05); JOA score at last follow-up (10.45 +/- 4.23) was significantly higher than that at preoperation (7.05 +/- 1.32) (P < 0.05); and cervical curvature value at last follow-up [(6.53 + 3.12) mm] was significantly higher than that at preoperation [(3.22 +/- 5.15) mm] (P < 0.05)., Conclusion: Combined posterior decompression with laminoplasty and anterior decompression with fusion for the treatment of cervical spinal canal stenosis with reverse arch is a safe and effective surgical method.

Objective: To summarize the characteristic imaging signs of ossification of the ligamentum flavum (OLF) associated with dural adhesions by analyzing retrospectively the imaging signs of OLF associated with dural adhesions., Methods: A retrospective analysis was made on clinical data of 85 patients undergoing OLF surgery between January 2010 and September 2012. The patients were assigned into the study group and the control group according to the preoperative imaging signs. Of 85 patients, 34 had both "tram track sign" and "jagged line sign" as the study group and 51 had either "tram track sign" or "jagged line sign" and neither of them as the control group. Adherence between dura mater and ligamentum flavum was observed during operation as the "gold standard" for the diagnosis of dural adhesion. The imaging information of CT and MRI in sagittal and axial planes was analyzed. The typical characteristics of dural adhesions were found. Then the sensitivity, specificity, and positive likelihood ratio of the preoperative imaging examinations were calculated to estimate the reference value and diagnostic value (> 5 having reference value, and > 10 having diagnostic value)., Results: In the study group, dural adhesion was observed in 26 patients (10 males and 16 females), and the other 8 patients (6 males and 2 females) had no dural adhesion. In the control group, dural adhesion was found in 2 female patients who had "jagged line sign", and 49 patients had no dural adhesion (14 males and 35 females). In patients having both "tram track sign" and "jagged line sign", the sensitivity was 92.9%; the specificity was 86.0%; and the positive likelihood ratio was 6.6. In patients having "tram track sign", the sensitivity was 92.9%; the specificity was 64.9%; and the positive likelihood ratio was 2.6. In patients having "jagged line sign", the sensitivity was 100%; the specificity was 77.2%; and the positive likelihood ratio was 4.4., Conclusion: For patients with OLF having both "tram track sign" and "jagged line sign", preoperative CT and MRI have a reference value for diagnoses of the OLF associated with dural adhesions.

Strong promoters might not be optimal to obtain maximum metabolic flux towards desired products, whereas modulating gene expression with multiple regulatory parts is an option to obtain optimal expression strength. Therefore, we assessed the difference of impact on beta-carotene production between modulating isoprenoid gene expression with multiple regulatory parts and strong promoter, to improve beta-carotene production through combined modulation of essential isoprenoid genes. Eight isoprenoid genes were modulated with six artificial regulatory parts having a wide range of strengths to assess their effects on beta-carotene production. Optimal strength for each isoprenoid gene expression was identified, leading to 1.2 to 3.5-fold increase in beta-carotene production. In contrast to previous reports, our work suggests that modulating dxr, ispG and ispH genes with appropriate strengths increase beta-carotene production. Beta-carotene yield reached 17.59 mg/g after combined modulation of dxs and idi genes, 8-fold higher than that of the parent strain. Modulating gene expression with multiple regulatory parts was better than strong promoter, providing a new gene modulation strategy for targeted biosynthesis.

Objective: To investigate the effect of different concentrations of fluoride on the expression of transforming growth factor-beta1 (TGF-beta1), and explore the mechanism of dental fluorosis., Methods: 40 Wistar rats were randomly divided into three groups, and supplied with low dose F(-)(60 mgxL(-1), 13 rats), high dose F(-)(120 mgxL(-1), 13 rats) and distilled water(control group, 14 rats) respectively. After 10 weeks, hematoxylin-eosin (HE) and immunohistochemistry staining were used to observe the changes of the ameloblasts and the expression of TGF-beta1 in rat incisors., Results: The fluoride groups showed typical symptoms of dental fluorosis. The surfaces of the rat teeth fed with fluoride appeared chalky color and cross striation on the enamel surface. The HE staining showed that the morphous of ameloblast were disarranged and cellular derangement, even appeared vacuolar change. TGF-beta1 were expressed both in ameloblast of the secretory and maturation stage, and also in stellate reticulum and stratum intermedium. The expression of TGF-beta1 in rat's ameloblasts in experiment group was significantly lower than that in the control group (P<0.01), yet low dose group and high dose group still had no significant difference (P>0.05)., Conclusion: By inhibiting the expression of TGF-beta1 in ameloblast, fluoride interferes the normal signal transduction between epithelial and mesenchymal, and affect the differentiation and development of enamel, so leading to the occurrence of dental fluorosis.

Objective: To evaluate and compare the relation of the clinical results of expansion of open-door cervical laminoplasty (EOLP), C5 nerve root palsy in hinge side, and reclose of the opened laminae with different angles in lamina open-door., Methods: Between July 2006 and January 2009, 198 patients with cervical myelopathy were treated by EOLP. According to different opening angles which were measured by CT scan after operation, the patients were divided into group A (> 30 degrees, 76 patients including 44 males and 32 females) and group B (15-30 degrees, 122 patients including 71 males and 51 females). There was no significant difference in gender, age, disease duration, and segmental lesions between 2 groups (P > 0.05). The Japanese Orthopaedic Association (IOA) score before and after operation was used for neurological assessment and improvement rate, and the postoperative C5 nerve root palsy and reclose of the opened laminae were recorded., Results: There was no significant difference in operation time, bleeding volume, and hospitalization days between 2 groups (P > 0.05). After 3 weeks of operation, C5 nerve root palsy in the hinge side occurred in 7 patients (9.2%) of group A, and in 2 patients (1.6%) of group B, were restored after symptomatic treatment, showing significant difference between 2 groups (chi2 = 4.568, P = 0.033). All patients were followed up 24 to 48 months. Between group A and group B, no significant difference was found in JOA improvement rate at 24 months after operation (P > 0.05), and in JOA score at preoperation and at 24 months after operation (P > 0.05), but JOA score was significantly improved at 24 months after operation when compared with preoperative score in the same group (P < 0.05). The function of limb lifting restored in 9 cases of C5 nerve root palsy at 24 months after operation; CT examination revealed that no reclose occured in group A and reclose occurred in 4 cases (3.3%) of group B, but no persistent symptoms or worsen situation were found during follow-up., Conclusion: Different angles in lamina open-door have the same clinical result; C5 nerve palsy has good prognosis. The opening angle between 15 degrees and 30 degrees will reduce the incidence of C5 nerve root palsy in the hinge side, but the open side should be firmly fixed to prevent further reclose of the opened laminae.

Objective: To evaluate the therapeutic effect of open-door cervical expansive laminoplasty (ELP) with anchor fixation on fluorosis cervical stenosis (FCS)., Methods: From February 2005 to February 2006, 20 patients with FCS underwent ELP using anchor fixation (group A) and 24 patients with FCS received ELP using conventional silk thread fixation (group B). In group A, there were 11 males and 9 females aged (58.0 +/- 11.2) years old, the course of disease ranged from 6 months to 5 years, and the stenosis involved 3 vertebral levels in 3 cases, 4 levels in 8 cases, and 5 levels in 9 cases, and the sagittal diameter of the cervical spinal canal was (7.30 +/- 5.23) mm. While in group B, there were 11 males and 13 females aged (61.0 +/- 9.1) years old, the course of disease ranged from 5 months to 5 years, the stenosis involved 3 vertebral levels in 5 cases, 4 levels in 10 cases, and 5 levels in 9 cases, and the sagittal diameter of the cervical spinal canal was (7.11 +/- 4.92) mm. No significant differences were evident between two groups in terms of the general information (P > 0.05). Before operation and at 24 months after operation, the nerve function was assessed by JOA score, the axial symptom (AS) was evaluated using Chiba 12-point method, and the changes of cervical lordosis index (CLI) and cervical range of motion (CRM) were detected by imaging examination., Results: All wounds healed by first intention. All patients were followed up for 24 months. JOA score: in group A, it was improved from 7.4 +/- 1.5 before operation to 14.6 +/- 2.1 at 24 months after operation with an improvement rate of 61% +/- 3%; in group B, the score was increased from 7.1 +/- 2.2 to 12.6 +/- 2.5 with an improvement rate of 52% +/- 5%; significant differences were evident in two groups between before and after operation, and between two groups in terms of the improvement rate (P < 0.05). AS score: in group A, it was improved from 6.2 +/- 2.1 before operation to 10.8 +/- 0.3 at 24 months after operation with an improvement rate of 74% +/- 4%; in group B, the score was increased from 6.3 +/- 1.9 to 8.8 +/- 0.5 with an improvement rate of 39% +/- 3%; significant differences were evident in two groups between before and after operation, and between two groups in terms of improvement rate (P < 0.05). X-ray films and CT scan at 24 months after operation displayed that there was no occurrence of "breakage of door spindle" or "re-close of door" in two groups, there was no occurrence of anchor loosing in group A, and the molding of the spinal canal was satisfactory in two groups. Preoperatively, the CLI was 11.9 +/- 1.9 in group A and 11.3 +/- 2.2 in group B and the CRM was (39.5 +/- 2.4) degrees in group A and (40.2 +/- 1.8) degrees in group B. While at 24 months after operation, the CLI was 9.5 +/- 2.2 in group A and 8.2 +/- 2.8 in group B, and the CRM was (30.6 +/- 2.0) degrees in group A and (28.7 +/- 2.4) degrees in group B, suggesting there was a significant decrease when compared with the preoperative value and group A was superior to group B (P < 0.05). The saggital diameter of the cervical spinal canal 24 months after operation was (13.17 +/- 2.12) mm in group A and (12.89 +/- 3.21) mm in group B, indicating there was a significant difference when compared with the preoperative value (P < 0.01)., Conclusion: Compared with conventional silk thread fixation, ELP using anchor fixation brings more stability to vertebral lamina, less invasion to the posterior muscular-skeletal structure of the cervical spine, slight postoperative neck AS, and satisfactory clinical outcomes.

Metabolic engineering has been developed for nearly 20 years since its beginning on 1990s, and it has significantly promoted the improvement of microbial fermentation industry. This review summarized the technology development and their applications in fermentation industry in each of the three important phases during the development of metabolic engineering. Finally, the key issues for future development and solving strategies were discussed.

Objective: To investigate the possibility of BMSCs seeded into collagen I -glycosaminoglycan (CG) matrices to form the tissue engineered cartilage through chondrocyte inducing culture., Methods: Bone marrow aspirate of dogs was cultured and expanded to the 3rd passage. BMSCs were harvested and seeded into the dehydrothemal treatment (DHT) cross-linked CG matrices at 1 x 10(6) cells per 9 mm diameter sample. The samples were divided into experimental group and control group. In the experimental group, chondrogenic differentiation was achieved by the induction media for 2 weeks. Medium was changed every other day in both experimental group and control group. The formation of cartilage was assessed by HE staining and collagen II immunohistochemical staining., Results: The examinations under the inverted phase contrast microscope indicated the 2nd and 3rd passage BMSCs had the similar morphology. HE staining showed the BMSCs in the experimental group appeared polygon or irregular morphology in the CG matrices, while BMSCs in the control group appeared fibroblast-like spindle or round morphology in the CG matrices. Extracellular matrix could be found around cells in the experimental group. Two weeks after seeded, the cells grew in the CG matrices, and positive collagen II staining appeared around the cells in the experimental group. There was no positive collagen II staining appeared in the control group., Conclusion: It is demonstrated that BMSCs seeded CG matrices can be induced toward cartilage by induction media.

Objective: To observe the apoptosis of human vascular smooth muscle cells (HVSMCs) transfected with p21 gene and investigate its potential mechanism., Methods: An adenoviral expression vector with full-length cDNA of p21 gene insert (Ad-p21) was constructed and transfected into HVSMC. A mock vector, pAdeno-X-lac Z constructed with the same method, was transfected into HVSMCs as control. Western blotting and DS-PAGE were used to detect the expression of p21 gene. Fluorescence staining was used to observe the changes in nuclei of apoptotic cells and calculate the cell survival rate. Expression of tissue transglutaminase (tTG) in HVSMC was examined by DIG-marked probe., Results: Fluorescence staining showed marked fragmentation of nucleus and pyknosis of chromatin in pAdeno-X-p21 transfected cells. The expression of tTG was at a higher level in pAdeno-X-p21 transfected cells than in normal cells and pAdeno-X-lac transfected HVSMCs., Conclusion: Overexpression of p21 gene inhibits the proliferation of HVSMC through apoptosis induced by p21 which may relate with overexpression of tTG.

In order to explore the role of p15(INK4B) gene with highly methylated CpG island in the pathogenesis of leukemia, the expression levels of p15(INK4B) gene was detected in patients with AML and CML. Methylation-specific PCR (MSP) assay was employed in the experiments. The methylation incidence was 83.9% (26/31) in AML and 0% (0/28) in CML. The results showed that methylation of p15(INK4B) gene was the one of the major ways for inactivation of the gene, and the methylation could be appeared in clinical development of the disease and patients condition worsened. Methylation of p15(INK4B) did not occur and its function probably is normal in CML.

To study the action, characteristics and expression of high methylation of p15(INK4B) and p16(INK4A) genes in multiple myeloma (MM), the sensitive methylation specific PCR method was employed to detect the hypermethylation of p15(INK4B) and p16(INK4A) in 24 patients with MM. Results showed that the methylation incidence of p15(INK4B) and p16(INK4A) genes were 70.8% (17/24) and 58.3% (14/24) in the MM patients, with the products of 148 bp and 150 bp fragments, respectively. The methylation of p15(INK4B) and p16(INK4A) genes were simultaneously happened in MM patients of plasmocytoma type with two cases at II phase and two cases at III phase. The simultaneous non-methylation of p15(INK4B) and p16(INK4A) genes were founded in five cases of MM patients, all of the tumor cells were of small plasmocyte type with mature differention. Conclusion suggested that there were high incidence of methylation of p15(INK4B) and p16(INK4A) genes in patients with MM. Hypermethylation can be detected in the early stage of disease, which was associated with its progress. It indicated a bad prognosis when methylation happended simultaneously in the two genes. Methylation of p15(INK4B) and p16(INK4A) genes may be related to the pathogeny of MM.