Cell-cycle deregulation leading to excessive cellproliferation is an important mechanism of human tumorigenesis. CDK6 and CDK4 have been found to be significant regulators of cellcycle, particularly in promoting cell -cycle progress. Moreover, these proteins are usually overly active in most tumors and closely related to tumor development. Recently, research has confirmed CDK4/6 as prospective targets for cancer therapy. However, the mechanism of excessive CDK6 activation leading to tumorigenesis is not completely understood. Therefore, further understanding of the role of CDK4/6 in cell -cycle regulatory pathways and celldifferenti-ation is essential, as well as their overexpression in different types of tumors. This information will elucidate the mechanisms of tumor development and treatment. Therefore, this review intends to discuss the structure and biological function of CDK6, the role and mecha-nism of CDK6 in carcinogenesis, and the clinical application of CDK6 inhibitors.

Objective To assess cerebrovascular reserve ( CVR) function in patients with internal border zone infarction(IBZI) induced by severe middle cerebral artery (MCA) stenosis, and investigate the impact on progression and outcome of the disease .Methods A total of 84 patients with unilateral severe MCA stenosis were selected . Hypercapnia was induced by holding breath .The change of blood flow velocity in MCA was measured by transcranial Doppler ( TCD ) to calculate CVR .According to CVR , patients were divided into impaired regional CVR group ( CVR <10%) and normal CVR group ( CVR ≥10%) .The NIHSS was used to evaluate neurological function in both groups within 14 d, and mRS was used to evaluate acute stage outcome of the patients at discharge .All the patients were followed-up for 6 months, the incidences of recurrence , complications and mortality in the two groups were analyzed .Results The incidence of progressive cerebral infarction in the impaired regional CVR group (67.39%) was significantly higher than that in the normal CVR group (42.11%) ( P<0.05).The impaired regional CVR group showed higher proportion of patients with poor clinical outcome at discharge ( mRS≥3 ) (63.04%)compared to the normal CVR group (36.84%) (P<0.05).In the followed-up 6 months, the incidences of recurrence and complications were 34.78% and 45.65% respectively in the impaired regional CVR group , they were significantly higher than that in normal CVR group (15.79%,23.68%)(P<0.05).The overall mortality rates did not differ significantly between the two groups ( P>0.05 ) .Conclusion Impaired regional CVR may be predictive of subsequent progressive cerebral infarction and poor clinical outcomes in patients with IBZI induced by severe MCA stenosis .

Background and purpose:Inhibitor of apoptosis-stimulating protein of p53 (iASPP) is one of the ASPP family. It binds to p53 to inhibit the transcriptional activity of p53-target genes and cell apoptosis, which is asso-ciated with tumor formation. Previously, we found a new subtype of iASPP, iASPP splice variant (iASPP-SV), which is a nuclear protein containing 407 amino acid residues and can bind to p53, inhibiting p53 transcriptional activity. However, the relationship of iASPP-SV and breast cancer is still obscure. Therefore, the purpose of this research was to study the role of iASPP-SV on breast cancer tumorigenesis and progression.Methods:5’-rapid ampliifcation of cDNA ends (RACE) was used to identify the 5’-end of iASPP-SV mRNA in MCF-7 cells. HEK 293 cells were transfected with pFLAG-iASPP-SV and pFLAG-iASPP (828). Then Western blot was used to identify whether endogenous iASPP-SV was expressed in HEK 293 cells and 8 types of human tumor cell lines. This study established the stable clones of NIH 3T3 expressing FLAG-iASPP-SV and FLAG-iASPP (828). Cell proliferation assay, colony formation and soft agar colony formation assay were used to identify whether iASPP-SV and iASPP (828) can promote cell proliferation and iASPP-SV is an oncogene. Real-time lfuorescent quantitative polymerase chain reactive (RTFQ-PCR) was used to de-tect the levels of iASPP-SV and iASPP (828) mRNA in primary breast cancers. Luciferase assays were used to identify the relationships between iASPP-SV, iASPP (828), p53 and NF-κB p65.Results:The study identiifed that iASPP-SV was encoded by previously reported NF-κB p65 subunit (RelA)-associated inhibitor (RAI), and endogenously expressed in many human cancer cell lines. Analysis of cell proliferation, colony formation assay and soft agar assay for colony formation identiifed that similarly to iASPP (828), iASPP-SV promoted tumor cell proliferation and acted as an onco-gene. RTFQ-PCR result showed that the median values of iASPP-SV and iASPP (828) in breast cancers with wild-type p53 were more signiifcantly over-expressed than those of mutant p53. Luciferase assays showed that iASPP-SV and iASPP (828) could suppress NF-κB p65 transcriptional activity. Thus iASPP family may participate in the regulation of p53 and NF-κB activity, which imply that iASPP perhaps shows pro- or anti-survival activities when it interacts with different proteins.Conclusion:These ifndings indicate that iASPP-SV may be a potential target for breast cancer thera-py.

Objective To introduce the outcomes of tracheal resection combined with primary end-to-end anastomosis for benign cervical tracheal stenosis,and to discuss the strategy for prevention of surgical complications.Methods The clinical data of 22 patients due to different causes benign cervical tracheal stenosis surgery were analyzed retrospectively.Results The length of cervical tracheal stenosis ranged was 2.2-4.2 cm.Grade Ⅱ stenosis was present in 6 patients.Grade Ⅲ stenosis was present in 11 patients and grade Ⅳ stenosis in 5 patients.Successful extubation was achieved in all 22 cases.After surgery,temporary hoarseness occurred to 1 case;unilateral pulmonary atelectasis with pleural effusion occurred to 1 case; subcutaneous emphysema with infection occurred to 1 case; mild dysphagia occurred to 3 cases;a slight deepening of the tone of voice in 10 patients with women occurred to 5 cases,granulation tissue growth near the suture occurred to 3 cases,and suture dehiscence did not occur in any patient.The follow-up period ranged from 6-45 months,no patient developed restenosis.Conclusions It presents a high success rate and good functional result of tracheal resection combined with primary end-to-end anastomosis.Therefore,it is an effective and reliable approach for the management of benign cervical tracheal stenosis.To avoid complications,the preoperative assessment,patients selection and postoperative management should be emphasized.

Since 2007, a number of published population-based studies have shown that stroke epidemiology has changed. There are some differences in morbidity, mortality, risk factors and clinical prognosis of stroke between the high-income countries and the less developed countries.

BACKGROUND:Preliminary experiments have reported the influence of serum and nerve growth factor on olfactory ensheathing cells proliferation in vitro, but there are less studies concerning choice of serum concentration and growth time for in vitro culture of olfactory ensheathing cells.
OBJECTIVE:To find out the influence of different blood serum concentration and growth time on olfactory ensheathing cells from the olfactory mucosa of adult rats based on the growth curve of olfactory ensheathing cells.
METHODS:The olfactory ensheathing cells from the olfactory mucosa of adult rats were separated, culture and identified in vitro. Sulforhodamine B and microplate reader were employed to measure absorbance values and plot growth curve of olfactory ensheathing cells.
RESULTS AND CONCLUSION:When cultured for the same time in blood serum of different concentrations, absorbance values, especial y in the groups 10%, 20%, 30%, 40%, tended to increase with time except the 0%group. When cultured in the same serum for different time, absorbance values increased within the first 9 days, then promoted rapidly in the groups 10%, 20%, 30%, 40%at 13 days, entered the plateau phase at 19 days, and decreased at 23 days;meanwhile, in the other groups (50%, 60%, 70%, 80%, 90%) the absorbance values peaked at the 13th day and then decreased gradual y. These findings indicate that different serum concentrations and different growth time in vitro affect cellgrowth and survival of olfactory ensheathing cells significantly, which should be ful y considered when cells are cultured in an in vitro condition.

Objective Hepatitis C virus patients are often accompanied by insulin resistance and diabetes.To probe the relative factors of abnormal glycometabolism in chronic HCV infections.Methods A total of 1 039 treatment-naive patients that were confirmed chronic HCV infected were enrolled in the study.The demographics,biochemical index parameters and other data about liver function and HCV viral load were got from infectious disease department of Jurong Pepole's Hospital in China.Results A total of 140 (13.5％) patients were diagnosed with some forms of abnormal glycometabolism.The body mass index (BMI) (x2 =9.231,P =0.010),waist circumference (x2 =7.984,P =0.018),systolic blood pressure (x2 =16.366,P ＜0.001),diastolic blood pressure (x2 =13.970,P =0.001),alanine aminotransferase(ALT) (x2 =4.809,P =0.028),HCV-RNA viral load (t =-3.818,P ＜0.001) were significantly different between non-diabetic HCV patients and abnormal glycometabolism patients.Multivariate logistic regression analysis showed that ALT(OR =2.986,95％ CI:1.171-7.615) and HCV-RNA viral load (OR =2.061,95％ CI:1.165-3.644) were found as risk factors in multivariate regression analysis for patients with chronic hepatitis C who had abnormal glucose metabolism.Conclusions Chronic hepatitis C patients with higher ALT and HCV-RNA level were more probably to suffer from abnormal glycometabolism.In order to find potentially novel risk factors of HCV with abnormal glucose metabolisn,further studies about genetic and other clinical factors need to be processed.

BACKGROUND:In recent years, chitosan-based thermosensitive hydrogel, as scaffold materials, have received more and more attentions in the field of tissue repair because of good biocompatibility, biodegradability and drug-sustained release.
OBJECTIVE:To explore the directed differentiation and growth of rat bone marrow mesenchymal stem cells on the quaternary chitosan thermosensitive hydrogel scaffold and to look for more ideal tissue engineering materials for the treatment of nervous system damage.
METHODS:The thermosensitive hygrogel scaffold was prepared using hydroxypropyltrimethyl ammonium chloride chitosan (HACC) andβ-glycerophosphate (β-GP). The spatial structure of scaffold was observed by scanning electronic microscope. Effect of leaching liquor from the HACC/β-GP scaffold on the viability of bone marrow mesenchymal stem cells was detected by (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The albumin from bovine serum was combined with the scaffold, and the slow-release effect of the scaffold was detected by ultraviolet absorption spectrometry. Bone marrow mesenchymal stem cells were incubated onto the compound scaffold at 3 passages. The adhesion, growth and differentiation of bone marrow mesenchymal stem cells on the compound scaffold were observed by the scanning electron microscope. Neuron-specific enolase was detected by immunofluorescence.
RESULTS AND CONCLUSION:The porosity and thermal sensitivity of HACC/β-GP scaffold and slow-release effect of glial cellline-derived neurotrophic factor were apparent. The results of MTT showed that the compound scaffold cannot take apparent negative effects to the proliferation of bone marrow mesenchymal stem cells. After inoculation, bone marrow mesenchymal stem cells permeated the porous structure of the scaffold and adhered to the scaffold. Under the role of glial cellline-derived neurotrophic factor, bone marrow mesenchymal stem cells showed neuron-like cellmorphology and cells co-cultured with the compound scaffold expressed the marker of neurons, neuron-specific enolase. Under the role of slow-release glial cellline-derived neurotrophic factor, bone marrow mesenchymal stem cells can grow wel in vitro and differentiate into neuron-like cells on the HACC/β-GP scaffold.

BACKGROUND:Scaffolds made of chitosan and its derivatives play an important role in cellmigration and axonal regeneration. Chitosan and its derivatives have good histocompatibility, which is easy to make stem cells grow on the surface, thereby having a more broad application prospect in the nerve tissue engineering.
OBJECTIVE:To fabricate a thermosensitive hydrogel scaffold using chitosan/hydroxypropyltrimethyl ammonium chloride chitosan/sodium glycerophosphate (CS/HACC/GP), which is suitable for cellgrowth, and then, to observe the growth and proliferation of bone marrow mesenchymal stem cells on the scaffold.
METHODS:Chitosan was modified using quaternary ammonium salt and confirmed by Fourier transform infrared spectroscopy. The chitosan and quaternary ammonium salt of chitosan was mixed at a ratio of 8:1 to successful y prepare stable CS/HACC/GP thermosensitive hydrogel scaffold. Then, the gel ing was observed, and biosafety test was conducted.
RESULTS AND CONCLUSION:Fourier transform infrared spectroscopy showed the characteristic peak of quaternary ammonium groups. Cytotoxicity test showed that rat bone marrow mesenchymal stem cells cultured in hydrogel extracts had no toxicity. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test showed that hydrogel extracts exerted no significant effect on the increase in body weight, and the biological safety of the scaffold was good. Under the scanning electron microscopy, bone marrow-derived mesenchymal stem cells grew and proliferated normal y in the scaffold. The results confirmed that the CS/HACC/GP thermosensitive hydrogel scaffold was successful y prepared in the experiment, which is suitable for the growth and proliferation of bone marrow mesenchymal stem cells.

BACKGROUND:Exogenous neurotrophic factors or chemical induction can induce rat bone marrow mesenchymal stem cells to differentiate into neuron-like cells. However, exogenous inductors exert a short inducible action, and their chemical substances inevitably have a negative impact on cellviability to limit the application prospects of bone marrow mesenchymal stem cells to a certain extent.
OBJECTIVE:To investigate the effect of glial cellline-derived neurotrophic factor, green fluorescent protein gene transfection by adenovirus vector on biological characteristics of rat bone marrow mesenchymal stem cells, to observe the expression of glial cellline-derived neurotrophic factor and green fluorescent protein and the role of nutrition on bone marrow mesenchymal stem cells, and to explore the ability to differentiate into neuron-like cells induced by glial cellline-derived neurotrophic factor.
METHODS:The bone marrow mesenchymal stem cells at passage 3 were transfected by recombinant adenovirus (Multiplicity of infection=10, 50, 80, 100, 150, 200). The experiment had two groups according to target genes:bone marrow mesenchymal stem cells were transfected by Ad-GDNF-GFP in transfection group, and bone marrow mesenchymal stem cells were not transfected in control group. The expression of green fluorescent protein was detected by inverted fluorescence microscope. Transfection efficiency was calculated by flow cytometry. cells viability and the morphological changes of cells were compared respectively by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and inverted fluorescence microscope between the two groups. On days 5 and 10 after transfection, the expression of glial cel-derived neurotrophic factor mRNA was detected by PCR. On day 5, the expression of neuron-specific enolase was determined by immunofluorescence examination. On day 10, the expression of microtubule-associated protein 2 was identified.
RESULTS AND CONCLUSION:By the end of 12 hours after transfection, the green fluorescent protein expressed in cells, and the fluorescence intensity gradual y increased with time. When the multiplicity of infection was 100, the fluorescence intensity was strong and stable, and the transfection rate was nealy 90%on day 3 after transfection. cellviability in the transfection group was strengthened after transfection. On day 5 after transfection, bone marrow mesenchymal stem cells expressed neuron-specific enolase, and neuron-like protrusions gradual y extended. On day 10 after transfection, bone marrow mesenchymal stem cells expressed microtubule-associated protein 2 and glial cellline-derived neurotrophic factor mRNA, and exhibited neuron-like morphology and interconnected synpases. The recombinant adenovirus, Ad-GDNF-GFP, can highly transfect bone marrow mesenchymal stem cells when the multiplicity of infection is 100, and glial cellline-derived neurotrophic factor can promote the proliferation of bone marrow mesenchymal stem cells and induce bone marrow mesenchymal stem cells to differentiate into neuron-like cells.