Microbial genome reduction and modification are important strategies for constructing cellular chassis used for synthetic biology. This article summarized the essential genes and the methods to identify them in microorganisms, compared various strategies for microbial genome reduction, and analyzed the characteristics of some microorganisms with the minimized genome. This review shows the important role of genome reduction in constructing cellular chassis.
Genes, Essential ; genetics ; Genetic Engineering ; Genome, Microbial ; genetics ; Synthetic Biology ; methods

Triple-negative breast cancer is defined by the absence of expression of oestrogen, progesterone, and Her-2 receptors. The clinicopathological characteristics include: higher histological grades, earlier relapse with worse prognosis, and a higher incidence of visceral metastases than bone metastases. Since it has no response to hormone treatment and targeted therapy for Her-2, chemotherapy became the main therapy. In addition, it may have a relationship with basal-like breast cancer and BRCA1-related breast cancer on the phenotype and molecular level. Inter-individual variations in DNA damage and repair have been associated with an increased risk of breast cancer. BRCA1 together with its associated genes such as BRCA2, ATM, RAD51 and CHEK2 play vital roles in different DNA repair pathways to preserve genome stability. Therefore variations of BRCA1 and its associated genes in multiple repair pathways may result in reduced DNA repair capacity and altered sensitivity to cytotoxic chemotherapeutic agents, which could promote incidence of distant metastases. Reduced DNA repair capacity and dysfunctional BRCA1 pathway in triple-negative breast cancer have been reported, however the detailed mechanisms are still unknown. Do the genetic variations of tumor cells or resistance of tumor cells to therapeutic drugs play the dominant role in high incidence of metastases in patients with triple-negative breast cancer? In this review, the association of dysfunctional BRCA1-related DNA repair pathways with high incidence of metastasis in triple-negative breast cancer would be introduced.

A series of epidemiological and experimental studies demonstrate a positive and significant association between exposure to particulate matter and cardiovascular-related incidence and hospitalization. Several possible mechanisms have been proposed,including vascular dysfunction,atherogenesis,arrhythmogenesis and oxidative stress and inflammation. So far the studies on the effect of particulate matter derived from dust events on cardiovascular diseases are limited,and different conclusions are drawn. The advances in recent studies were reviewed in this paper,and suggestions for further research were made.

Objective To research the effect of GANT61 on epithelial‐mesenchymal transition (EMT) in human lung cancer H1703 and A549 cells lines ,and to preliminarily investigate its action mechanism .Methods DMSO was used as the control(DMSO group) .After treating H1703 and A549 cells with GANT61 for 24 h ,the gene changes of Gli‐1 ,Gli‐2 ,E‐cadherin and Vimentin were detected by using the real time fluorescence quantitative PCR method .The influence of GANT61 on the expression of E‐cad‐herin and Vimentin protein after acting on H1703 and A549 cells was observed by using the Western blotting assay .The scratch healing test was performed to evaluate the effect of GANT 61 on the tumor cell invasion ability after acting on H1703 and A549 cells .Results The real time fluorescence quantitative PCR showed that ,compared with the DMSO group ,GANT61 down‐regulated the mRNA expression of Gli‐1 ,Gli‐2 and Vimentin mRNA of H1703 and A549 cell lines and elevated the expression of E‐cadherin protein(P<0 .01);the Western blotting showed that GANT61 down‐regulated the expression of Vimentin of H1703 and A549 cell lines ,and elevated the expression of E‐cadherin(P<0 .01);the scratch healing test revealed the invasion ability of H 1703 and A549 cells in the GANT61 treatment group was significantly decreased (P<0 .01) .Conclusion EMT in lung cancer is related with aber‐rant activations of Gli1 and Gli2 in Hedgehog signal transduction pathway ,GANT61 could influence the EMT ability in lung cancer cells by down‐regulating the expression of Gli‐1 and Gli‐2 .Gli could become a new molecular target for inhibiting the lung cancer cell metastasis.

Polyunsaturated fatty acids (PUFAs) are important structural fatty acids of biological membrane. They play important roles in regulation of lipid metabolism,stimulation of growth and development,protection a gainst cancer,retardation of aging,immuno-regulation, cardiovascular health,and bodymass loss. In recent years, researchers have found t hat ω-6 PUFAs can promote tumor angiogenesis,while ω-3 PUFAs have the properties of inhibiting tumor angiogenesis. This review focuses on the effects of these two types of fatty acids on tumors,especially on the regulation of tumor angiogenesis.

BACKGROUND:The studies about biomechanics of total knee arthroplasty were more, but the research on finite element analysis of the effect of total knee arthroplasty on proximal tibial reconstruction was not much.
OBJECTIVE:To study the effect of total knee arthroplasty on proximal tibial reconstruction using finite element analysis.
METHODS:We designed knee models of two materials:one was functional y graded material models of col agen and titanium composite materials;another was titanium al oy material model. We created two prosthesis material tibia-knee prosthesis model, and analyzed bone density distribution of proximal tibia, the maximum stress value of the medial tibia and the lateral tibia, and the maximum stress value of medial tibia and prosthesis junction, as wel as lateral tibia and prosthesis junction after knee arthroplasty.
RESULTS AND CONCLUSION:(1) Bone density of proximal tibia after total knee arthroplasty:The bone density of the knee prosthesis handle with medial and lateral tibia at the junction of tibial plateau was decreased than that of the initial state. Stress shielding effect was lower in col agen and titanium composite materials of functional y graded material models than that of titanium al oy material model. The bone density of shank end of the tibial prosthesis was obviously increased compared with the medial and lateral tibia, showing stress concentration. (2) The maximum stress value of the medial and the lateral tibia:The maximum stress value of the medial and the lateral tibia in col agen and titanium composite models was lower than that of titanium al oy material model. The maximum stress values of the lateral tibia of col agen and titanium composite models and titanium al oy material model were lower than that of medial tibia. (3) The maximum stress of medial tibia, lateral tibia and prosthesis junction:The stress distribution of col agen and titanium composite models was relatively uniform. The stress distribution of titanium al oy material model showed fluctuation. Stress concentration appeared in pal ets and prosthesis junction and the shank end of the prosthesis. The maximum stress values of lateral tibia and prosthesis junction of col agen and titanium composite models and titanium al oy material model were lower than that of medial tibia and prosthesis junction. (4) These findings showed that knee prosthesis has a certain stress shielding effect on tibia after total knee arthroplasty. The stress shielding effect of col agen and titanium composite material prosthesis was lower than titanium al oy material prosthesis, and could improve tibial incurred stress.

AIM: To investigate the effects of tripchlorolide (TP) on proliferation and autophagy of human lung cancer A549 cells, and explore its mechanism.METHODS: MTT assay was performed to analyze the effect of TP on the viability of human lung cancer A549 cells.The A549 cells were treated with TP, and their autophagy was observed un-der the fluorescence microscope through acridine orange staining.Green fluorescence spots were observed by fluorescence microscopy through GFP-LC3 plasmid transfection experiment.The levels of LC3 and p-ERK in the A549 cells after TP treatment were determined by Western blot.RESULTS: The viability of human lung cancer A549 cells was significantly inhibited by TP in a dose-time dependent manner (P <0.05).The number of the intracellular acidic follicles dyed with bright red fluorescence was significantly increased after TP treatment in A549 cells.The number of green dot-like con-gregate autophagosomes in cell cytoplasm was significantly increased after TP treatment in the A549 cells transfected with GFP-LC3 plasmid, while the normal treatment only induced a few cells with autophagosome formation.At the same time, we did not observe the dot-like congregate autophagosomes after TP treatment in the A549 cells transfected with GFP-control plasmid.Compared with control group, the expression of LC3-II protein was up-regulated in A549 cells after TP treatment (P <0.01).Furthermore, treatment with TP in A549 cells for 48 h also led to a significant upregulation of phosphorylated form of ERK (P <0.01).In contrast, no significant change in the levels of total ERK protein was observed.Compared with 100 nmol/L TP group, TP +3-MA group down-regulated the protein levels of LC3-II (P <0.01) and p-ERK (P <0.01) in the A549 cells.CONCLUSION: TP significantly inhibits the growth of A549 lung cancer cells and induces the
autophagy, which may be correlated with upregulation of p-ERK protein.

Objective To explore the independent influencing factors on the survival of patients with cervical cancer .Methods Five hundreds and nintheen surgery patients with cervical cancer ,and hospitalized in the Tumor Hospital Affiliated to Harbin Medical University between January 2007 and December 2008 were cho-sen as our research object .We analyzed the influence of different biological behaviors on the outcome of patients with cervical cancer by using univariate and multivariate COX regression ,and then explored the prognostic factors of patients with cervical cancer.Results Among all biological behaviors,tumor size(P=0.015),lymph node metastasis(P<0.001),ovarian metastasis(P<0.001),utero-tissue infiltration(P<0.001),vaginal stump(P=0.040),myometrial in -vasion(P=0.001)and lymph vascular space involvement (P<0.001)affected pa-tients′outcomes significantly.The results of univariate COX regression showed that the tumor size (RR=2.325), histological grade(RR=3.195),lymph node metastasis(RR=3.196),ovarian metastasis(RR=7.016),utero-tissue infiltration(RR=7.487),myometrial invasion(RR=4.688)and lymph vascular space involvement (RR=4.014)were significantly associated with the prognosis of cervical cancer .In addition,the results of multivariate COX regression indicated that histological grade (RR=2.092),ovarian metastasis(RR=5.680),utero-tissue infiltration(RR=4.114),myometrial invasion(RR=2.065)and lymph vascular space involvement (RR=3.11) were significantly associated with the prognosis of cervical cancer .Conclusion Histological grade ,ovarian metas-tasis,utero-tissue infiltration,myometrial invasion and lymph vascular space involvement were independent influ -encing factors of prognosis of cervical cancer .

The concept of white matter dementia was first introduced by Filley in 1988.It was found following behavioral neurologica researches that patients with this type of dementia manifested the dysfunctions of sustained attention,memory retrievial,frontal lobe and visualspatial function.They also had psychiatric manifestations but language and extrapyramidal function remained normal.10 diseases of white matter disorders are listed for understanding the clinical characteristics of this type of dementia.

Objective To discuss the injury spectrum and traumatic condition spectrum of trauma of abdominal organs in recent years. Methods Data of 247 cases with trauma on abdominal organ admitted in our hospital from 1999 to 2001 were analyzed in respects of injury spectrum, sex, age, vocation and injury causes of the cases with trauma of abdominal organs. Traumatic condition was evaluated by abridged injury score-injury severity score (AIS-ISS). Results There were 54 cases with trauma of abdominal organs in 1999, 72 in 2000 and 121 in 2001. Of all, 241 cases were cured but 6 died, with a fatality rate of 2.5%. The occurrence frequency of trauma of abdominal organs could be ranked in turn as follows: the spleen (43.2%), the kidney (18.8%), the liver (13.7%), the small intestine (6.5%),the bladder (4.8%), the pancreas (3.8%), the colon (3.8%), the stomach, the duodenum and the rectum. A total of 192 cases at age under 40 years accounted for 77.7% . Three injury causes ranked the first three places were traffic accident in 95 cases (38.5%), fall in 54 (21.9%), kick and boxing in 36 (14.6%), respectively. Of all, 168 cases had only intraabdominal injuries, of which 80 (47.6%) were with AIS=3, 32 (19.0%) with AIS=4 and 10 (6.0%) with AIS=5; and the other 79 cases (32.0%) were complicated by multiple trauma, with ISS ≥16 in 27 cases (34.2%) and ISS ≥25 in 8 (10.1%). Conclusions With the increase of vehicles and current personnel, the trauma of abdominal organs caused by traffic accident, accidental wound and conflict increases accordingly. People most apt to organ injuries are farmers, students and workers. Three organs ranked first three places are the spleen, the kidney and the liver. More than half cases are injured severely in accordance with AIS. To decrease trauma of abdominal organs, we must strengthen the education on traffic safety to raise their bewareness of injuries.