The occurrence rate of colorectal cancer is increasing. Metastasis and recurrence are the leading causes of death in colorec-tal cancer. Tumor cells in the circulation have the ability to proliferate or to migrate, thereby providing a reliable means for neoplasm staging and assessment of recurrence or metastasis, and evaluation of efficacy by detecting circulating tumor cells (CTC). Optimizing the development of detection technology will provide better support for clinical applications. This review mainly discusses CTC detec-tion and advances in colorectal cancer relapse or metastasis.

BACKGROUND:Intervertebral disc can bear load but lack vessels. Nucleus pulposus cel s have the problem of phenotype loss during in vitro culture that can lead to degenerative changes. The mechanism of intervertebral disc degeneration remains unclear.
OBJECTIVE:To explore the approaches of isolation, adherence culture, amplification and identification of the rabbit nucleus pulposus cel s in vitro, to observe the growth characteristics of nucleus pulposus cel s in different generations.
METHODS:Type Ⅱ col agenase digestion method plus explants culture method was used to isolate and purify nucleus pulposus cel s and then amplify in vitro. The morphology and growth of primary and passaged cel s was observed under the inverted microscope, the number of cel s was counted and the growth curve was draw. The morphology of the cel s was observed under light microscope after hematoxylin-eosin staining, and the expressions of col agen type Ⅱ and aggrecan were examined by immunocytochemistry.
RESULTS AND CONCLUSION:Nucleus pulposus cel s of rabbit were isolated, cultured and amplified in vitro successful y. Growth activity was observed, and found that the 1-3 generation nucleus pulposus cel s proliferated more rapidly and vigorously. The proliferation of nucleus pulposus cel s was decreased while the cel passaged more generations. These isolated and cultured nucleus pulposus cel s could positively express the col agen type Ⅱ and aggrecan. In vitro combination of type Ⅱ col agenase digestion method and explants culture method could obtain high purity nucleus pulposus cel s, and the cultured nucleus pulposus cel s were grew in round or polygonal. The 1-3 generation of cel s had strong activity.

Purpose Many studies have shown that subclinical left ventricular systolic dysfunction is seen in prediabetic patients.However,its relationship with prognosis is unclear.The purpose of this study is to investigate the prognostic value of subclinical left ventricular systolic dysfunction with prediabetes.Materials and Methods This was a prospective clinical cohort study.A total of 98 prediabetes patients with complete medical record and follow up data in the physical exam center and the clinic of Yan'an People's Hospital were chosen between January 2013 and January 2014.The biochemical data,echocardiography and left ventricular global longitudinal strain (GLS) in 2 years of follow up were collected.The subjects were grouped into diabetes if the diagnosis was confirmed during follow up,or non-diabetes group if not diagnosed.After follow up,the baseline parameters were compared to screen for risk factors to develop clinical diabetes.Results During the study,38 participants were diagnosed as clinical diabetes.Cox proportional hazard regression models show that obesity [hazard ratio (HR):2.662,95％ CI 1.374-5.159,P=0.004],waist-hip ratio (HR:1.917,95％ CI:1.012-3.492,P=0.001),mitral E/e'ratio (HR:1.661,95％ CI:1.336-2.065,P＜0.001),HbAlc (HR:2.029,95％ CI:1.047-3.932,P＜0.001),global longitudinal strain (HR:0.786,95％ CI:0.728-0.848,P＜0.001) were significant independent predictors for developing diabetes.Using GLS＜18％ as cutoff value,the area under receiver operating characteristic (ROC) curve to predict development of diabetes was 0.796 (95％ CI:0.704-0.888,P＜0.001),with sensitivity and specificity of 46.7％ and 89.5％,respectively.Conclusion Among modifiable risk factors in patients with prediabetes,subclinical left ventricular systolic dysfunction is an early indicator of progressing to diabetes.Early detection of left ventricular systolic dysfunction in prediabetes can provide the basis for early clinical intervention.

Objective To explore the effects of the cervical vertebra rehabilitation gymnastics on patients with different types of cervical spondylosis (CS). Methods 203 patients with different types of CS were selected. They were trained with rehabilitation gymnastics. The electrophysiological examination of neck-shoulder muscles were used to evaluate the effects 3 and 6 months after training. Results The peak of electrophysiological action potential of neck- shoulder muscles was significantly different in all the types of CS patients (P<0.001), as well as the conduction velocity of action potential (P<0.05) before and 3, 6 months after training. There was significantly different in scores of subjective symptoms in sympathetic cervical spondylosis and cervical spondylotic radiculopathy patients (P<0.001), but was not in the other types (P>0.05) before and 3, 6 months after training. Conclusion The cervical vertebra rehabilitation gymnastics can promote blood circulation of neck-shoulder muscles, relieve muscle spasm and ease the symptoms, especially for patients with cervical spondylotic radiculopathy and sympathetic cervical spondylosis.

Chromosomal integration enables stable phenotype and therefore has become an important strategy for breeding of industrial Saccharomyces cerevisiae strains. pAUR135 is a plasmid that enables recycling use of antibiotic selection marker, and once attached with designated homologous sequences, integration vector for stable expression can be constructed. Development of S. cerevisiae strains by metabolic engineering normally demands overexpression of multiple genes, and employing pAUR135 plasmid, it is possible to construct S. cerevisiae strains by combinational integration of multiple genes in multiple sites, which results in different ratios of expressions of these genes. Xylose utilization pathway was taken as an example, with three pAUR135-based plasmids carrying three xylose assimilation genes constructed in this study. The three genes were sequentially integrated on the chromosome of S. cerevisiae by combinational integration. Xylose utilization rate was improved 24.4%-35.5% in the combinational integration strain comparing with that of the control strain with all the three genes integrated in one location. Strain improvement achieved by combinational integration is a novel method to manipulate multiple genes for genetic engineering of S. cerevisiae, and the recombinant strains are free of foreign sequences and selection markers. In addition, stable phenotype can be maintained, which is important for breeding of industrial strains. Therefore, combinational integration employing pAUR135 is a novel method for metabolic engineering of industrial S. cerevisiae strains.
Genetic Engineering ; methods ; Genetic Vectors ; Metabolic Engineering ; Plasmids ; genetics ; Saccharomyces cerevisiae ; genetics ; Xylose ; metabolism

Objective Our previous study demonstrated that toll-like receptor 2(TLR2) can distinguish extraneous antigen and prevent the immunological response. This study was designed to detect the expression of toll-like receptor 2 (TLR2) mRNA in cornea and investigate the effect of steroid on TLR2 expression in rats cornea following allograft penetrating keratoplasty. Methods The penetrating keratoplasty models were established in SPF rats with the 108 SD rats as receiptors and 36 SPF Wistar rats as donors, and other 6 SPF SD rats worked as normal controls. The receiptor rats were divided randomly into autograft group, allograft group and steriod group. The clarity and neovascularization of corneas of experiment rats were examined under the slit-lamp microscope and the rejection index was calculated based on Holland criteria. Corneal histopathological examination was carried out by hemotoxylin and eosin staining under the light microscope, and real time-PCR was employed for the detect of TLR2 mRNA in the corneas at the fifth, seventh and ninth day after operation. The experimental animals were obtained from the Animal Experimental Center of Southern Medical University and the procedure followed the Statement of Association for Research in Vision and Ophthalmology. Results The rejection occurred in 7 days after operation in allograft group, and only mild edema, opacity and neovascularization of corneas were found at different degrees in 9 days after operation in autograft group and steriod group. Severe corneal edema, a lots of inflammatory cells infiltration and new vessels in stroma were seen in allograft group, and mild inflammatory response was found in autograft group and steriod group. Normal comeal structure was exhibited in normal control group under the light microscope. The fold differences of TLR2 mRNA expression in cornea after amplification was significantly different among three groups and different time points (F_(group) = 39. 46, P = 0. 00; F_(time) =35. 38, P = 0. 00 ; F_(interaction) = 45. 66, P =0. 00), and the evident enhance of TLR2 mRNA expression was revealed in allograft group compared with autograft group (P ＜ 0. 05) and declined in steriod group (P ＜ 0. 05). Conclusion Steriod may restrain the acute allograft rejection by down-regulating the expression of TLR2 in corneas and its signals transaction. This result suggests that steriod offer a protection from rejection of cornea after penetrating keratoplasty.

Objective To explore the function and clinical effect of automatic nerve retractor in micro-endoscopic discectomy.Methods From August 2009 to December 2010,350 patients with lumbar disc hemiation were treated by micro-endoscopic discectomy,including 196 males and 154 females,aged from 17 to 68 years (average,42 years).Three cases were at L1-2,8 at L2-3,12 at L3-4,186 at L4-5 and 141 at L5S1.The automatic nerve retractor was used in all micro-endoscopic discectomy.The visual analogue scale (VAS) and Oswestry disability index (ODI) were used to evaluate clinical outcomes.Results All patients were followed up for 6 to 16 months (average,9 months).The mean VAS score decreased from preoperative 8.79±1.15 to 3.80±1.14 3 months after operation and 3.65±1.14 6 months after operation.The mean ODI score decreased from preoperative 78％±1.71％ to 28％±1.72％ 3 months after operation and 28％±1.88％ 6 months after operation.Postoperative VAS and ODI scores decreased significantly compared with those before operation.The VAS and ODI scores 6 months after operation were not significantly improved compared with those 3 months after operation.No spinal cord and nerve root injury and epidural hematoma formation occurred in all cases.Conclusion In micro-endoscopic discectomy,the automatic nerve retractor can help the operator obtain effective exposure,protect nerves from injury,alleviate workload of the operators,therefore it has a great clinical application value.

BACKGROUND:Transplantation of mesenchymal stem cels to prevent and treat degeneration of the intervertebral disc is a feasible method. Mesenchymal stem cels co-transfected by SRY-related high mobility group-box gene 9 (SOX-9) and growth differentiation factor-5 (GDF-5) can differentiate into nucleus pulposus cels, in order to obtain greater effect of induction and proliferation of nucleus pulposus cels. OBJECTIVE:To investigate the effect of SOX-9 and GDF-5 co-transfection on the differentiation of rabbit bone marrow mesenchymal stem cels into nucleus pulposus cels. METHODS: We separated and cultured bone marrow mesenchymal stem cels from the bone marrow of rabbit aged 4 months. Passage 3 cels were divided into five groups andin vitro induced to differentiate into nucleus pulposus cels: non-transfected group, empty vector transfection group, SOX-9 transfection group, GDF-5 transfection group, SOX-9 and GDF-5 co-transfection group. At 14 days after transfection, RT-PCR was employed to assay SOX-9, GDF-5 and colagen type II mRNA expressions in bone marrow mesenchymal stem cels. The marker of nucleus pulposus cels-KRT19 expression was also detected by immunohistochemical staining. RESULTS AND CONCLUSION:In the co-transfection group, the mRNA expressions of SOX-9, GDF-5, and colagen type II were significantly higher than those in the SOX-9 transfection group, GDF-5 transfection group, and both these two groups, respectively (P < 0.05). Cels were positive for KRT19 in the SOX-9 and GDF-5 groups, and strongly positive for KRT19 in the co-transfection group. These findings indicate that double gene-transfected bone marrow mesenchymal stem cels are better than single gene-transfected cels with regard to differentiation into nucleus pulposus cels and secretion of extracelular matrix.

Objective To investigate the effects of alpha lipoic acid on patients with diabetic retinopathy (DR),explore the possible mechanisms,and provide experimental evidence for the treatment of DR with lipoic acid.Methods Totally 75 DR patients were randomly divided into control group and treatment group.Patients in control group received the standard hypoglycemic treatment,antihypertensive therapy,and other comprehensive treatment.Patients from the treatment group were treated with alpha lipoic acid 600 mg + 250 ml 0.9％ sodium chloride injection additionally,avoiding light intravenous therapy,for a total of 4 weeks.Before and after treatment,fundus fluorescein angiography and visual inspection were detected in two groups.In addition,serum level of asymmetric dimethylarginine (ADMA) were detected with high performance liquid chromatography,serum lipid peroxidation product malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were detected to reflect the in vivo oxidative stress before and after treatment in two groups.Results Compared to the control group,visual acuity was improved significantly (P ＜ 0.05),and total efficiency of ocular lesions-improved was increased significantly (84.21％ vs 40.54％,x2 =15.28,P ＜ 0.01).Serum levels of endogenous inhibitor of nitric oxide synthase ADMA [(0.32 ±0.13) μmol/L vs (0.51 ± 0.26) μmol/L,P ＜ 0.05] and MDA [(3.22 ± 0.90) nmol/L vs (5.13 ± 0.42) nmol/ml,P ＜ 0.05] were significantly decreased,while SOD levels [(72.68 ± 1.31) U/ml vs (53.16 ± 1.54) U/ml,P ＜0.05] were significantly increased in DR patients after alpha lipoic acid treatment.Conclusions Alpha lipoic acid had some therapeutic effects for DR patients,which mainly lied in the improvement of visual acuity and eye disease,might be related to the decrease of oxidative stress and serum level of endogenous nitric oxide synthase (NOS) inhibitor ADMA.

In order to improve students' overall quality,Biomedical Engineering College of Chongqing Medical University has carried out quality development training in the 6 session of the 450 students.The content includes development projects,the queue training,humanities lectures,inspirational film etc.; the objective is to develop the students' mind,develop their team spirit and interpersonal communication skills.College has recruited and assisted professional instructors in the whole training.The centralized training in specific situations gives students a strong spiritual shock and strong positive energy.Before and after the training we use the same questionnaire to students,the results of which have shown that their comprehensive ability,EQ,and cohesion of the class have been improved.