Application of tissue engineering in the treatment of stress urinary incontinence

Stress urinary incontinence is one of the most common diseases in urology. The main treatments for stress urinary incontinence are pharmacotherapy, physicobehavioral therapy and surgery.However, the results of present methods are not satisfactory. Tissue engineering is a newly emerging technology that may provide a novel method for the treatment of stress urinary incontinence.     

脑胶质瘤放化疗后复发和假性进展的鉴别

1病历摘要 患者男性,66岁,因“右颞间变型少突星形细胞瘤Ⅲ级术后10个月”入院。患者曾于2012—03．23因“左下肢乏力3天,伴全身抽搐1次”收住我院神经外科。2012—04—16在全麻下行右颞开颅肿瘤切除术,     

Future application of hair follicle stem cells: capable in differentiation into sweat gland cells

Background Sweat glands (SGs) can not regenerate after complete destruction in the severe skin injury,so it is important to find a ideal stem cell source in order to regenerate functional SGs.Hair foll...     

Effects of notch-1 down-regulation on malignant behaviors of breast cancer stem cells

This study examined the effect of Notch-1 signaling on malignant behaviors of breast cancer cells by regulating breast cancer stem cells （BCSCs）. BCSCs were enriched by using serum-free me- dium and knocked out of Notch-1 by using a lentiviral vector. Real-time polymerase chain reaction （RT-PCR） and Western blotting were used to detect the Notch-1 expression levels in breast cancer cell lines and BCSCs, and fl0w cytometry to detect the proportion of BCSCs in BCSC spheres. The BCSC self-renewal, migration, invasion, and tumorigenicity were examined by the tumor microsphere-forming assay and transwell assay and after xenotransplantation. The results showed that the Notch-1 silencing reduced the number of BCSC spheres, the proportion of BCSCs, and the number of cells penetrating through the transwell membrane. It also decreased the size of tumors that were implanted in the nude mice. These results suggest that Notch-1 signaling is intimately linked to the behaviors of BCSCs. Blocking Notch-1 signaling can inhibit the malignant behaviors of BCSCs, which may provide a prom- ising therapeutical approach for breast cancer.     

Amplification of functional myeloid-derived suppressor cells during stem cell mobilization induced by granulocyte colony-stimulation-factor

The effects of granulocyte colony-stimulation-factor （G-CSF） on stem cell mobilization and its impact on the amplification of myeloid-derived suppressor cells （MDSCs） of donor mice were ex- amined. A mouse model of stem cell mobilization was established by consecutive subcutaneous injec- tion of 100 μg/kg G-CSF for 5 days. The blood from the donor mice was routinely examined during mobilization. Stem cells and MDSCs were analyzed by flow cytometry. The immunosuppressive mole- cules derived from MDSCs in serum and spleen, including hydrogen dioxide （H202） and nitric oxide （NO）, and the activity of nitric oxide synthase （NOS） were determined during the mobilization. Apop- tosis of T lymphocytes was assessed by using Annexin-V/PI. During stem cell mobilization, the number of lymphocytes and white blood cells in the peripheral blood was increased, and peaked on the 4th day. The number of stem cells in G-CSF-treated mice was significantly greater than that in controls （P〈0.01）. The expansions of MSDCs were also observed after G-CSF mobilization, with a more notable rate of growth in the peripheral blood than in the spleen. The activity of NOS and the production of NO were increased in the donor mice, and the serum H202 levels were approximately 4-fold greater than the con- trois. Consequently, apoptosis of T lymphocytes was increased and showed a positive correlation with the elevated percentage of MDSCs. It was concluded that G-CSF could provide sufficient peripheral blood stem cells for transplantation. Exogenous administration of G-CSF caused the accumulation of MDSCs in the peripheral blood and the spleen, which could lead to apoptosis ofT lymphocytes and may offer a new strategy for the prevention and treatment of graft versus host disease.     

Preparation of PLLA/bpV（pic） Microspheres and Their Effect on Nerve Cells

In this study, we prepared PLLA/bpV（pic） microspheres, a bpV（pic） controlled release system and examined their ability to protect nerve cells and promote axonal growth. PLLA microspheres were prepared by employing the o/w single emulsification-evaporation technique. Neural stem cells and dorsal root ganglia were divided into 3 groups in terms of the treatment they received： a routine medium group（cultured in DMEM）, a PLLA microsphere group（DMEM containing PLLA microspheres alone） and a PLLA/bpV（pic） group [DMEM containing PLLA/bpV（pic） microspheres]. The effects of PLLA/bpV（pic） microspheres were evaluated by the live-dead test and measurement of axonal length. Our results showed that PLLA/bpV（pic） granulation rate was（88.2±5.6）%; particle size was（16.8±3.1）%, drug loading was（4.05±0.3）%; encapsulation efficiency was（48.5±1.8）%. The release time lasted for 30 days. In PLLA/bpV（pic） microsphere group, the cell survival rate was（95.2 ±4.77）%, and the length of dorsal root ganglion（DRG） was 718±95 μm, which were all significantly greater than those in ordinary routine medium group and PLLA microsphere group. This preliminary test results showed the PLLA/bpV（pic） microspheres were successfully prepared and they could promote the survival and growth of neural cells in DRG.     

Osteogenic differentiation of bone mesenchymal stem cells regulated by osteoblasts under EMF exposure in a co-culture system

This study examined the osteogenic effect of electromagnetic fields （EMF） under the simulated in vivo conditions. Rat bone marrow mesenchymal stem cells （BMSCs） and rat osteoblasts were co-cultured and exposed to 50 Hz, 1.0 mT EMF for different terms. Unexposed single-cultured BMSCs and osteoblasts were set as controls. Cell proliferation features of single-cultured BMSCs and osteoblasts were studied by using a cell counting kit （CCK-8）. For the co-culture system, cells in each group were randomly chosen for alkaline phosphatase （ALP） staining on the day 7. When EMF exposure lasted for 14 days, dishes in each group were randomly chosen for total RNA extraction and von Kossa staining. The mRNA expression of osteogenic markers was detected by using real-time PCR. Our study showed that short-term EMF exposure （2 h/day） could obviously promote prolifera- tion of BMSCs and osteoblasts, while long-term EMF （8 h/day） could promote osteogenic differen- tiation significantly under co-cultured conditions. Under EMF exposure, osteogenesis-related mRNA expression changed obviously in co-cultured and single-cultured cells. It was noteworthy that most osteogenic indices in osteoblasts were increased markedly after co-culture except Bmp2, which was increased gradually when ceils were exposed to EMF. Compared to other indices, the expression of Bmp2 in BMSCs was increased sharply in both single-cultured and co-cultured groups when they were exposed to EMF. The mRNA expression of Bmp2 in BMSCs was approximately four times higher in 8-h EMF group than that in the unexposed group. Our results suggest that Bmp2-mediated cellular interaction induced by EMF exposure might play an important role in the osteogenic differ- entiation of BMSCs.     

Construction of self-assembled cartilage tissue from bone marrow mesenchymal stem cells induced by hypoxia combined with GDF-5

It is widely known that hypoxia can promote chondrogenesis of human bone marrow de- rived mesenchymal stem cells （hMSCs） in monolayer cultures. However, the direct impact of oxygen tension on hMSC differentiation in three-dimensional cultures is still unknown. This research was de- signed to observe the direct impact of oxygen tension on the ability of hMSCs to ＂self assemble＂ into tissue-engineered cartilage constructs, hMSCs were cultured in chondrogenic medium （CM） containing 100 ng/mL growth differentiation factor 5 （GDF-5） at 5% （hypoxia） and 21% （normoxia） 02 levels in monolayer cultures for 3 weeks. After differentiation, the cells were digested and employed in a self- assembly process to produce tissue-engineered constructs under hypoxic and normoxic conditions in vi- tro. The aggrecan and type ]I collagen expression, and type X collagen in the self-assembled con- structs were assessed by using immunofluorescent and immunochemical staining respectively. The methods of dimethylmethylene blue （DMMB）, hydroxyproline and PicoGreen were used to measure the total collagen content, glycosaminoglycan （GAG） content and the number of viable cells in each con- struct, respectively. The expression of type II collagen and aggrecan under hypoxic conditions was in- creased significantly as compared with that under normoxic conditions. In contrast, type X collagen expression was down-regulated in the hypoxic group. Moreover, the constructs in hypoxic group showed more significantly increased total collagen and GAG than in normoxic group, which were more close to those of the natural cartilage. These findings demonstrated that hypoxia enhanced chondro- genesis of in vitro, scaffold-free, tissue-engineered constructs generated using hMSCs induced by GDF-5. In hypoxic environments, the self-assembled constructs have a Thistological appearance and biochemical parameters similar to those of the natural cartilage.     

Advances in mesenchymal stem cells combined with traditional Chinese medicine therapy for liver fibrosis

Liver fibrosis is a primary cause of liver cirrhosis, and even hepatocarcinoma. Recently, the usage of mesenchyrnal stem cells （MSCs） has been investigated to improve liver fibrosis. It has been reported that the differentiation, proliferation and migration of MSCs can be regulated by traditional Chinese medicine treatment; however, the mechanisms are still unclear. In this article, the authors review the characteristics of MSCs such as multidirectional differentiation and homing, and its application in animal experiments and clinical trials. The authors also list areas that need further investigation, and look at the future prospects of clinical application of MSCs.     

Association between intervertebral disc degeneration and disturbances of blood supply to the vertebrae

Low back pain is a common public health problem in western industrialized societies and the world as well.Studies indicate that the prevalence rate ranges to 35%, with around 10% of patients from 12% becoming chronically disabled. It also places an enormous economic burden on society. Although the exact cause of low back pain has yet to be defined, intervertebral disc degeneration is considered a major source of it. Since patients with degenerative discs are often asymptomatic, the mechanisms of it are still unclear.     

Allogeneic compact bone-derived mesenchymal stem cell transplantation increases survival of mice exposed to lethal total body irradiation: a potential immunological mechanism

Background Radiation-induced injury after accidental or therapeutic total body exposure to ionizing radiation has serious pathophysiological consequences,and currently no effective therapy exists.This study was designed to investigate whether transplantation of allogeneic murine compact bone derived-mesenchymal stem cells （CB-MSCs） could improve the survival of mice exposed to lethal dosage total body irradiation （TBI）,and to explore the potential immunoprotective role of MSCs.Methods BALB/c mice were treated with 8 Gy TBI,and then some were administered CB-MSCs isolated from C57BL/6 mice.Survival rates and body weight were analyzed for 14 days post-irradiation.At three days post-irradiation,we evaluated IFN-Y and IL-4 concentrations; CD4＋CD25＋Foxp3＋ regulatory T cell （Treg） percentage; CXCR3,CCR5,and CCR7 expressions on CD3＋T cells; and splenocyte T-bet and GATA-3 mRNA levels.CB-MSC effects on bone marrow hemopoiesis were assessed via colony-forming unit granulocyte/macrophage （CFU-GM） assay.Results After lethal TBI,compared to non-transplanted mice,CB-MSC-transplanted mice exhibited significantly increased survival,body weight,and CFU-GM counts of bone marrow cells （P＜0.05）,as well as higher Treg percentages,reduced IFN-Y,CXCR3 and CCR5 down-regulation,and CCR7 up-regulation.CB-MSC transplantation suppressed Th1 immunity.Irradiated splenocytes directly suppressed CFU-GM formation from bone marrow cells,and CB-MSC co-culture reversed this inhibition.Conclusion Allogeneic CB-MSC transplantation attenuated radiation-induced hematopoietic toxicity,and provided immunoprotection by alleviating lymphocyte-mediated CFU-GM inhibition,expanding Tregs,regulating T cell chemokine receptor expressions,and skewing the Th1/Th2 balance toward anti-inflammatory Th2 polarization.     

Diagnosis and treatment of epistaxis caused by non-traumatic pseudoaneurysms of carotid artery

Epistaxis remains one of the most common otolaryngology emergencies. Severe epistaxis may be caused by internal carotid artery （ICA） pseudoaneurysm or cavernous fistula, which is clinically rare but life threatening if it is not diagnosed and treated timely. Most ICA pseudoaneurysms are mainly caused by trauma with few other causes. From January 1998 to December 2005, a total of 8 cases with non-traumatic carotid artery pseudoaneurysm were correctly diagnosed through digital subtraction angiography （DSA） in Ganzhou People＇s Hospital. The patients had suffered from serious nose bleeding repeatedly and had been resistant to routine treatments.     

Saffron （Crocus sativus L.） and major depressive disorder： a meta-analysis of randomized clinical trials

Due to safety concerns and side effects of many antidepressant medications, herbal psychopharmacology research has increased, and herbal remedies are becoming increasingly popular as alternatives to prescribed medications for the treatment of major depressive disorder （MDD）. Of these, accumulating trials reveal positive effects of the spice saffron （Crocus sativus L.） for the treatment of depression. A comprehensive and statistical review of the clinical trials examining the effects of saffron for treatment of MDD is warranted. OBJECTIVE： The purpose of this study was to conduct a meta-analysis of published randomized controlled trials examining the effects of saffron supplementation on symptoms of depression among participants with MDD. SEARCH STRATEGY： We conducted electronic and non-electronic searches to identify all relevant randomized, double-blind controlled trials. Reference lists of all retrieved articles were searched for relevant studies. INCLUSION CRITERIA： The criteria for study selection included the following： （1） adults （aged 18 and older） with symptoms of depression, （2） randomized controlled trial, （3） effects of saffron supplementation on depressive symptoms examined, and （4） study had either a placebo control or antidepressant comparison group. DATA EXTRACTION AND ANALYSIS： Using random effects modeling procedures, we calculated weighted mean effect sizes separately for the saffron supplementation vs placebo control groups, and for the saffron supplementation vs antidepressant groups. The methodological quality of all studies was assessed using the Jadad score. The computer software Comprehensive Meta- analysis 2 was used to analyze the data. RESULTS： Based on our pre-specified criteria, five randomized controlled trials （n = 2 placebo controlled trials, n = 3 antidepressant controlled trials） were included in our review. A large effect size was found for saffron supplementation vs placebo control in treating depressive symptoms （M ES = 1.62, P 〈 0.001）, revealing that saffron supplementation significantly reduced depression symptoms compared to the placebo control. A null effect size was evidenced between saffron supplementation and the antidepressant groups （M ES = -0.15） indicating that both treatments were similarly effective in reducing depression symptoms. The mean Jadad score was 5 indicating high quality of trials. CONCLUSION： Findings from clinical trials conducted to date indicate that saffron supplementation can improve symptoms of depression in adults with MDD. Larger clinical trials, conducted by research teams outside of Iran, with long-term follow-ups are needed before firm conclusions can be made regarding saffron＇s efficacy and safety for treating depressive symptoms.     

高维列联表资料的统计分析与SAS软件实现（六）

非条件logistic回归分析方法的主要算法是采用最大似然法对参数进行估计。最大似然法在大样本前提下进行参数估计是非常有效的,但当处理样本量小的数据,特别是按多个定性变量进行分层且每一层中样本量很小时,     

痘苗病毒天坛株的减毒与其作为疫苗载体研究进展

1痘苗病毒天坛株的历史天花是人类历史上最可怕的传染病之一。天花由天花病毒（variola virus）引起,人是该病毒的惟一宿主。人感染天花病毒后的死亡率达到30%~40%[1]。世界上公认的对天花最早的准确记录来自中国,晋代药学家葛洪于公元430年左右,在《肘后备急方》中对天花有清楚的描述[1]。