In 2010, the artificial synthesis of Mycoplasma mycoides triggers the new era of synthetic biology. This great breakthrough is achieved mainly thanks to the powerful DNA recombinant ability of yeast. In recent years, except for the methods used for large DNA assembly on the basis of in vivo homologous recombination, various different DNA assembly methods in vitro, based on the concept of DNA ligation or polymerization, have also been developed, such as Biobrick\BglBrick, SLIC and Gibson one-step assembly. Application of these new technologies has greatly accelerated the construction of synthetic part libraries, biosynthetic pathway and even microbial chromosomes. In fact, all DNA assembly methods are derived from the combinations of DNA joining and organizational schemes. This review describes the brief introduction of the main in vivo and in vitro DNA assembly protocols developed so for, which will benefit the construction of different types of synthetic functional devices and also biosynthetic pathways in the research of synthetic biology in China.
DNA ; biosynthesis ; chemistry ; genetics ; DNA, Recombinant ; biosynthesis ; genetics ; Genetic Engineering ; methods ; Metabolic Networks and Pathways ; Synthetic Biology ; methods

Objective To investigate the correlation between Kruppel-like transcription factor 6 (KLF6) and gastric cancer.Methods By using immunohistochemistry (IHC) and reverse transcription PCR,the expression of KLF6 protein and mRNA in human gastric carcinoma specimens and adjacent tissues from 73 patients were examined.Results The KLF6 protein expression rates were 39.7 ％ (29/73) and 90.41％(66/73) in 73 cases of gastric cancer and adjacent tissues,The KLF6 protein expression was significantly lower in human gastric carcinomas than the adjacent tissues by chi-square test (P ＜ 0.01).The KLF6 expression rates were 25.0 ％ (10/40),57.6 ％ (19/33) in poorly and well differentiated cancer.The difference between the two groups was significant (P ＜ 0.01).The optical density ratio of KLF6 mRNA were 0.1586±0.1071 and 0.8899±0.0638 in the gastric cancer and cancer adjacent tissue respectively,the difference between the two groups was significant (P ＜ 0.01).Conclusion KLF6 expression is low in gastric carcinoma,and moreover,KLF6 expression is significantly lower in poorly differentiated cancers than the well differentiated gastric cancers,there are negative correlation between KLF6 and gastric cancer,therefore KLF6 could be a useful marker for gastric cancer.

Objective To investigate the correlation and clinical diagnosis significance between ultrasound elastography and the distribution of myofibroblast in breast tumor.To assess the value of ultrasonic elastography and myofibroblast in the diagnosis of breast cancers.MethodsThree-hundred and fifteen patients recruited from May 2009 to November 2010 were divided into benign group and malignant group according to postoperative pathological diagnosis results considered as gold standard.The clinical value of the score of ultrasonic elastography was evaluated.The expression levels of CD34 and α-SMA protein in breast tissues were examined by immunohistochemistry.ResultsThe difference was statistically significant for the expression level of CD34 and α-SMA between malignant breast tumor patients compared with benign ( P ＜0.05).The expression level of CD34 was lower,but α-SMA was higher in the patients of breast cancer compared with benign tumor.However,the expression level of CD34 and α-SMA was just the opposite in the patients of benign tumor.The expression level of CD34 was the negative correlation with the elastography score ( P ＜0.05) in the breast tumor,but α SMA just the opposite situation.Conclusions The score of ultrasound elastography can represent MFS distribution characteristics in breast tumors in the result that α-SMA +/CD34- can determine the existence of myofibroblast.

Objective To evaluate the left ventricular(LV)global and segmental myocardial systolic function in patients with permanent DDD pacemaker implantation by speckle tracking imaging.Methods Myocardial imaging of LV apical long views and parasternal LV short axis views were performed in 9 patients with right ventricular(RV)septum pacing(RV septum group),15 patients with RV apex pacing(RV apex group)and 13 healthy subjects(control group).Peak systolic longitudinal strain(S_L),peak systolic radial strain(S_R)were measured,and the average of S_L and S_R among LV 18 segments were calculated respectively as corresponding GS_L and GS_R.Results The GS_L[-(18.29±2.67)%]of RV apex group showed significant decrease compared with RV septum group[-(20.54±2.29)%]and control group[-(21.07±2.08)%](P＜0.05),while no significant difference was found between RV septum and control group.The GS_R of the pacing groups were both lower than control group[(36.26±9.37)%in control group,(28.59±6.06)%in RV septum group,(26.85±7.73)%in RV apex group,P＜0.05],but RV apex group showed more decrease trend.The S_L and S_R of the LV myocardial segments close to the pacing sites in both pacing groups showed significant decrease compared with control group,but RV septum group preserved similar LV strain distribution with control group while RV apex group showed abnormal LV strain pattern.Conclusions Speckle tracking imaging is a useful modality to evaluate global and segmental myocardial systolic function of LV with pacing at different right ventricular sites.

Purpose To discuss the clinical pathological features, diagnosis and differential diagnosis, treatment and prognosis of pri-mary breast diffuse large B-cell lymphoma ( DLBCL) . Methods 7 cases of primary breast DLBCL were collected, their clinical path-ological characteristics and immunophenotypes were also observed, and the treatment and prognostic factors were discussed. Results All of the 7 patients were women, aged 28~75 years, with the median 51 years. 5 cases involved left breast, 2 cases were located in the right breast. Painless mammary mass and ipsilateral axillary lymphadenopathy were the commonest clinical manifestations. On mi-croscopic observation, tumor cells were large to medium-sized which characterized as diffuse infiltration between the lobules of mamma-ry gland, around the duct, interstitial and fat tissue, some were single file cord pattern. 1 case was ALK-1 positive DLBCL, 6 cases were DLBCL of the non special type. The immunophenotype showed 5 cases were of non-GCB, 2 cases were of GCB type. Ki-67 index were from 60% to 95%. According to Ann Arbor staging, 2 cases were stage I EA, 5 cases were stage II EA. IPI score:4 cases with 0 score, 3 cases with 1 score. Of 7 patients, one case was modified radical mastectomy, 4 cases were lumpectomy, 2 cases were diag-nosed by core needle biopsy. 2 patients died without chemotherapy, 5 patients were chemotherapy or radiotherapy for 4 to 6 cycles ( CHOP/R-CHOP) , 4 patients received complete response, one died. Patients were followed up from 1 to 114 months, the median fol-low-up time was 18 months. The 1 year OS rate was 57. 1%, 5 years OS rate was 14. 3%. Conclusion The diagnosis of primary breast DLBCL is confirmed by pathological biopsy and immunohistochemical markers. The immunophenotype was mainly non-GCB type. Comprehensive treatment including chemotherapy and radiotherapy is appropriate. The prognosis should be comprehensively eval-uated by multiple factors.

For lack of cognitive screening standard system and controversy over the value of imaging for cerebrovascular diseases in China, the research group of Alzheimer′s Disease Chinese (ADC) studied the knowledge of neuropsychology, neuroimaging and clinical neurology, systematically reviewed the diagnostic techniques such as memory, language, visuospatial, executive, function, and magnetic resonance imaging (MRI) of cerebrovascular diseases, and their optimal threshold and diagnostic value for vascular dementia. Via a consensus meeting, the diagnostic guidelines and practical screening process are combined to construct a framework in Chinese population, which is based on the objective evidence of medical history and clinical evaluation. The diagnosis of vascular dementia is supported by imaging evidence of cerebrovascular diseases and differentiates from other causes of dementia or comorbidities. This consensus is applicable to medical units in China, and is of great significance for early detection, early diagnosis and early treatment of vascular dementia.

Criteria for diagnosis of Alzheimer's disease (AD) is not available in China.The international criteria is not a proper choice due to issues such as translation and lead to low diagnostic rate and high rate of missed diagnosis.The research group of Alzheimer's Disease Chinese (ADC) reviewed knowledge and techniques in neuropsychology,neuroimaging,molecular biology,and clinical neurology,and systematically studied the detection techniques such as memory,language,visuospatial,executive function,and medial temporal lobe visual scores on MRI,and their optimal threshold and diagnostic value for the diagnosis of AD.Through a systematic review and consensus meeting,a diagnostic framework for screeningAD in the Chinese population was established.Among these methods,an operational standard for clinical pathology models increased the diagnostic sensitivity by 15％.The sensitivity and specificity of screening memory impairment increased by 18.1％ and 11.6％,respectively.The sensitivity of screening medialtemporal lobe atrophy increased by 24.5％ and missed diagnosis was decreased by 34.5％.An operational standard for clinical biology models,incorporating the latest molecular imaging and molecular biology techniques,has enabled the early diagnosis of AD in China.The framework combines a principled diagnostic guideline with an operational screening protocol,which is applicable to all clinical settings and of great significance for the early detection,early diagnosis and early treatment of AD.

There are no standard diagnostic criteria for Alzheimer′s disease (AD) in China. The copied international criteria has led to a high rate of missed diagnosis due to issues such as translation and cultural discrepancy. Under the principles of semantic equivalence, content equivalence and performance equivalence, the research group of Alzheimer′s Disease Chinese (ADC) adopted several effective methods, such as two-way translation, content conversion, performance evaluation, etc. to systematically study the cognitive, behavioral, functional, and general assessment techniques in dementia screening and diagnosis, as well as their screening thresholds and diagnostic values. We also established a dementia screening and assessment framework in clinical practice through systematic reviews and group consensus. It has improved the early diagnosis rate of dementia in China, been accepted by home and abroad academic institutions, which is of great significance for early diagnosis and treatment of dementia.

Objective To reveal the virulence genes and the polymorphisms of chromosomal 16S rRNA gene of Yersinia enterocolitic strains isolated from different districts in Jiangsu Province,2015. Methods Five virulence genes(ail,virF,yadA,ystA and ystB)of Yersinia enterocolitic strains isolated from different districts in Jiangsu Province were detected by using polymerase chain reaction(PCR),and phylogenetic analysis of chromosomal 16S rRNA gene was performed by amplification and sequencing. Results In this study,73 Yersinia enterocolitic strains were collected in Jiangsu Province in 2015.Among them,56(76.7%)strains carried virulence genes,and ail-virF-yadA -ystA -ystB+were the dominate types in diarrhea patients and other hosts.All strains can be clustering into 4 groups according to the phylogenetic analysis of chromosomal 16S rRNA gene.Conclusions The non-pathogenic Yersinia enterocolitic(ystB+)is the dominant strain in Jiangsu province,and the pathogenic strains are also found in this region.The result of phylogenetic analysis of chromosomal 16S rRNA gene and the profiles of virulence genes are highly consistent.