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71.
Emergency surgical repair for acute traumatic aortic ruptures has been associated with a high peri-procedural mortality rate. Endovascular stent-grafting, as a less invasive procedure, has shown encouraging results. This report describes a patient with a short landing zone, who was treated by transposing the supra-aortic branch without sternotomy, followed by covered stent-grafting with an extended proximal bare portion to enhance fixation.  相似文献   
72.
Four osteosarcoma cell lines, Saos-2, MG-63, G-292 and U-2 OS, were reprogrammed to pluripotent state using Yamanaka factors retroviral transduction method. Embryonic stem cell (ESC)-like clusters started to appear between 15 to 20 days post transduction. Morphology of the colonies resembled that of ESC colonies with defined border and tightly-packed cells. The reprogrammed sarcomas expressed alkaline phosphatase and pluripotency markers, OCT4, SSEA4, TRA-1-60 and TRA-1-81, as in ESC up to Passage 15. All reprogrammed sarcomas could form embryoid body-like spheres when cultured in suspension in a low attachment dish for up to 10 days. Further testing on the directed differentiation capacity of the reprogrammed sarcomas showed all four reprogrammed sarcoma lines could differentiate into adipocytes while reprogrammed Saos-2-REP, MG-63-REP and G-292-REP could differentiate into osteocytes. Among the 4 osteosarcoma cell lines, U-2 OS reported the highest transduction efficiency but recorded the lowest reprogramming stability under long term culture. Thus, there may be intrinsic differences governing the variable responses of osteosarcoma cell lines towards reprogramming and long term culture effect of the reprogrammed cells. This is a first report to associate intrinsic factors in different osteosarcoma cell lines with variable reprogramming responses and effects on the reprogrammed cells after prolonged culture.  相似文献   
73.
Self-assembled nanostructures consisting of BMP receptor-binding peptides, termed osteopromotive domains (OPDs), and hydrophobic alkyl chains were fabricated with the aim of developing three-dimensional scaffolding materials for osteoblastic differentiation. OPD peptide was identified from BMP-2 and had an affinity for BMP receptors thereby inducing differentiation of human bone marrow stromal cells into osteoblastic cells. The peptide-hydrophobic alkyl chain amphiphiles were designed to mimic nanofibrous extracellular structures and to add osteogenic ligands to enhance osteoblastic cell function. The OPD peptide-amphiphiles (OPDAs) that end with the alkylation of the N-terminus of the OPD peptide were synthesized by standard solid phase chemistry. The self-assembly was triggered by mixing OPDA solution with calcium ions. Observation using scanning electron microscopy (SEM) revealed the formation of nanofibrous structures with extremely high aspect ratios and high surface areas. The FT-IR and circular dichroism (CD) spectrophotometry demonstrated that self-assembled nanofibers have a β-sheet structure. The activation of Smad, an osteoblastic differentiation marker, was obtained in the cell culture gel of self-assembled OPDA; therefore, the intracellular signal transduction for osteogenesis was performed like an OPD peptide. Cell survival was supported in the OPDA gel for 10 days, and osteoblastic differentiation of human bone marrow stromal cells (hBMSCs) was evident as demonstrated by calcein staining and ALP activity measurement. These results revealed that self-assembled OPDA maintained osteogenic activity by the surface-exposed OPD peptide. Taken together, the self-assembled OPDA nanofibrous gel can be utilized as a cell culture scaffold in bone regeneration.  相似文献   
74.
Heavy alcohol consumption is associated with an increased risk of erectile dysfunction (ED); however, the acute effects of ethanol (EtOH) on penile tissue are not fully understood. We sought to investigate the effects of EtOH on corporal tissue tonicity, as well as the intracellular Ca^2+ concentration ([Ca^2+]i) and potassium channel activity of corporal smooth muscle. Strips of corpus cavernosum (CC) from rabbits were mounted in organ baths for isometric tension studies. Electrical field stimulation (EFS) was applied to strips precontracted with 10 μmol L^-1 phenylephrine as a control. EtOH was then added to the organ bath and incubated before EFS. The [Ca^2+]i levels were monitored by the ratio of fura-2 fluorescence intensities using the fura-2 loading method. Single-channel and whole-cell currents were recorded by the conventional patch-clamp technique in short-term cultured smooth muscle cells from human CC tissue. The corpus cavernosal relaxant response of EFS was decreased in proportion to the concentration of EtOH. EtOH induced a sustained increase in [Ca^2+]i in a dose-dependent manner, Extracellular application of EtOH significantly increased whole-cell K^+ currents in a concentration-dependent manner (P 〈 0.05). EtOH also increased the open probability in cell-attached patches; however, in inside-out patches, the application of EtOH to the intracellular aspect of the patches induced slight inhibition of Ca^2+-activated potassium channel (KCa) activity. EtOH caused a dose-dependent increase in cavemosal tension by alterations to [Ca^2+]i. Although EtOH did not affect KCa channels directly, it increased the channel activity by increasing [Ca^2+]i. The increased corpus cavemosal tone caused by EtOH might be one of the mechanisms of ED after heavy drinking.  相似文献   
75.

Introduction and hypothesis  

We evaluated the efficacy of transurethral injection (TUI) for the treatment of recurrent or persistent stress urinary incontinence after mid-urethral sling (MUS) procedures.  相似文献   
76.

Background  

The aim of this study is to assess skin strength in MWL patients relative to control cosmetic abdominoplasty patients biophysically, biochemically, and histologically. Growing success of weight loss programs has brought about an increase in the MWL population. Skin quality is thought to be impaired by MWL, but there are no compelling studies that have fully addressed the structural mechanisms involved.  相似文献   
77.
78.
Charcot-Marie-Tooth disease type 1A (CMT1A) and hereditary neuropathy with liability to pressure palsies (HNPP) are the two most common peripheral neuropathies, with incidences of about 1 in 2,500. Several techniques can be used to detect the typical 1.5-Mb duplication or deletion associated with these respective conditions, but none combines simplicity with high sensitivity. MLPA is a new technique for measuring sequence dosage. We have assessed its performance for the detection of the specific 1.5-Mb duplication/deletion by prospectively testing 50 patients referred with differential diagnoses of CMT or HNPP. Probes were designed to evaluate the TEKT3, PMP22, and COX10 genes within the CMT1A/HNPP region. We have compared the results with our existing fluorescence in situ hybridization (FISH) assay, which was performed in parallel. There was concordance of results for 49 patients. Of note, one patient showed an intermediate multiplex ligation-dependent probe amplification (MLPA) result with an abnormal FISH result, which is consistent with mosaicism. The assay works equally well with either purified DNA or rapid DNA preparations made by direct cell lysis. The use of the latter significantly reduces the cost of the assay. MLPA is a sensitive, specific, robust, and cost-effective technique suitable for fast, high-throughput testing and offers distinct advantages over other testing methods.  相似文献   
79.
Lee HH  Cha SC  Jang DJ  Lee JK  Choo DW  Kim YS  Uh HS  Kim SY 《Virus genes》2002,25(2):179-188
The immunity of a combined DNA vaccine of HSV-2 glycoproteins B2 (gB2) and D2 (gD2) genes in comparison to individual vaccines was studied with regard to protecting against the HSV infection. Two recombinant DNA vaccines of the pHS2-gB2 or pHS2-gD2 were constructed and formulated. The neutralizing antibody titers appeared higher in the B2:D2 gene cocktail-vaccinated mice than that of the individual B2 or D2 gene-vaccinated group alone, and the positive KOS control induced higher titer of the neutralizing antibody than combined or individual gene vaccines. The mock-immunized mice failed to induce enough. The ranks for the CTL activity and the protection rates against the lethal intravaginal challenge were shown as KOS>B2:D2 cocktail>D2>B2 gene vaccines. The vaginal external diseases in the B2:D2 or D-vaccinated mice were significantly reduced against the challenging dosages. The virus titers in the vaginal secretions of the vaccinated mice significantly reduced with time, and the B2:D2 gene vaccine decreased more than each individual vaccine alone. It can be concluded that the cocktailed vaccines are more effective in the humoral and cellular immune responses in the mice, and in the protection of the mice against the intravaginal challenging dosages when compared with individual gene vaccines. All the DNA vaccines failed to block the latent infection in sensory nerves.  相似文献   
80.
Adolescence is a sensitive period for changes in both sleep and affect. Although past research has assessed the association between affect and sleep among adolescents, few studies have examined both trait (typical) and day‐to‐day changes in affect, and fewer still have specifically examined negative social evaluative emotions (e.g. embarrassment) in relation to sleep. Both between‐ and within‐person variations in daily affect were examined in relation to four objectively‐measured sleep outcomes (sleep hours; sleep latency; sleep efficiency; and length of wake bouts) among adolescents. Participants (N = 77 high‐school students; 42.9% female; M = 14.37 years) wore an actiwatch and completed daily‐diaries for 3 days. The results of hierarchical linear models (controlling for age, gender, race, ethnicity, parental employment status, income, puberty and caffeine) indicated that negative social evaluative emotions and high‐arousal affective experiences generally predicted poor sleep outcomes, whereas low‐arousal affective experiences were associated with good sleep outcomes. Specifically, at the person level, adolescents reporting higher negative social evaluative emotions had shorter average sleep hours, and those experiencing higher anxiety–nervousness had longer wake bouts. In addition, individuals experiencing more dysphoria (sad, depressed, lonely) had longer average sleep hours and shorter wake bouts, while those experiencing more calmness had shorter sleep latencies. At the within‐person level, individuals had longer sleep latencies following days that they had experienced high‐arousal positive affect (e.g. excitement), and had longer wake bouts following days they had experienced more negative social evaluative emotions. The results highlight the detrimental effects of negative social evaluative emotions and high‐arousal affective states for adolescent sleep.  相似文献   
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