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991.
OBJECTIVES: Autologous bone marrow implantation (BMI) is effective to treat critical limb ischemia, but the long-term prognosis is not clear. The outcome of BMI treatment for ischemic legs was investigated related to the clinical background of the patient, and short-term effects of BMI. The end event was defined as unexpected lower limb amputation. METHODS AND RESULTS: This study included 21 consecutive patients (mean age 60.0 +/- 13.6 years) with peripheral arterial disease who underwent BMI between December 2001 and March 2005. Twelve patients had arteriosclerosis obliterans (ASO), 5 had Buerger disease (thromboangiitis obliterans), 3 had thromboembolism, and 1 had hypereosinophilic syndrome. The patients with ASO had severe complications such as diabetes and hyperlipidemia. The total number of transplanted CD34-positive cells, ankle-brachial pressure index (ABI), and tissue oxygen pressure (TcO2) were lower in ASO patients than non-ASO patients. Significant risk factors for the event were diagnosis of ASO and low TcO2 (< 30 mmHg) according to the Kaplan-Meier survival curve and log rank test. All 6 patients who required limb amputation had ASO simultaneously with low TcO2 (6 of 9, 67%). In contrast, there was no correlation between the end event and short-term effect of BMI such as improvements in ABI and TcO2. CONCLUSIONS: Treatment with BMI could not save legs in some patients with ASO associated with severe leg ischemia.  相似文献   
992.
993.
994.
Malaria infection during pregnancy is associated with adverse consequences including low birth weight (LBW) and maternal anemia, particularly in primigravidae and secundigravidae. In preparation for a clinical trial of the efficacy of chloroquine (CQ) and sulfadoxine-pyrimethamine (SP) containing prevention regimens during pregnancy, we conducted a one-year cross sectional study in Koro and Bandiagara, Mali using an assessment methodology developed by the Centers for Disease Control and Prevention (CDC) to generate basic data on malarial burden during pregnancy. Two hundred and sixty-one and 192 women were enrolled in Koro and Bandiagara, respectively. Rates of placental parasitemia were 17.1 and 42.3% in Koro and Bandiagara, respectively, despite high (70-80%) use of preventive medication (mainly CQ). Low gravidity (1st and 2nd pregnancies) was associated with peripheral (p<0.001) and placental (p<0.001) malaria only in Bandiagara, whereas it was associated with low birth weight in both sites (p<0.001 in Koro and p=0.002 in Bandiagara). First and second pregnancies were the most important characteristics associated with placental malaria (RR=2.78, 95%CI 1.81-4.29) and (ARR=2.06, 95%CI 1.03-4.15) and low birth weight (RR=4.26, 95%CI 2.50-7.27) and (ARR=4.51, 95%CI 2.55-8.00). Birth during the rainy season was associated with placental infection in univariate analysis. Characteristics such as younger age, having fever during pregnancy, and unmarried status were associated with low birth weight only in univariate analysis and singleton premature delivery and low gravidity were associated with low birth weight in both univariate and multivariate analysis. Data from this assessment demonstrated the high burden of malaria during pregnancy in Mali. Results had been used by researchers as local reference data and by ministry of health for to stop recommending CQ prophylaxis. The methodology could be used by other malaria-endemic countries to direct their national malaria program efforts.  相似文献   
995.
The strong Brønsted acid‐promoted group transfer polymerization (GTP) of N,N‐dimethylacrylamide (DMAA) using trifluoromethanesulfonimide (Tf2NH) and 2,3,4,5,6‐pentafluorophenyl‐1,1‐bis(trifluoromethanesulfonyl)methane (Tf2CHC6F5) was carried out to quantitatively evaluate the effect of the counter anions for the employed acid on the kinetics and the stereoregularity of the polymerization. The equilibrium constant for the monomer activation (K) and the rate constant for the propagation reaction (kp) were determined from the integrated rate equation derived from the presumed polymerization mechanism. Both of the constants for the polymerization using Tf2CHC6F5 were higher than those for Tf2NH. The activation parameters for the syndiotactic propagation were determined from the Fordham plot.  相似文献   
996.
A 62-year-old male developed metachronous aortic aneurysms at different locations over an interval of one year and three months. He was diagnosed to have sarcoid aneurysms due to the presence of noncaseating epithelioid granulomas in the aortic wall and lymph nodes. The patient was treated with steroids, but his sarcoidosis progressed gradually and extended into other major organs, and the lungs and heart were clinically determined to have been involved by sarcoidosis. He died of cardiac tamponade four years after the first operation for an aortic aneurysm.  相似文献   
997.
A 40-year-old Japanese man was admitted to our hospital for evaluation of upper abdominal pain. Abdominal computed tomography (CT) revealed a well-circumscribed multicystic mass measuring approximately 7 × 6 cm. The mass contained a solid lesion measuring 3 × 2 cm. Biopsy of a swollen cervical lymph node led to a diagnosis of diffuse large B-cell lymphoma. After initial chemotherapy for lymphoma, the multicystic mass was surgically resected. The tumor was composed of a multicystic lesion and a solid lesion. Histopathologic examination of the multicystic lesion revealed that the locules were lined by biliary epithelium, demonstrating various degrees of cytological atypia. The stroma was fibrous, and the tumor showed marked apocrine snouts. Part of the tumor showed papillary growth with strong cytological atypia. The solid lesion showed tubulocystic proliferation of tumor cells, with prominent apocrine snouts, embedded in dense and partially hyalinized fibrous stroma. The morphology of the solid part was quite similar to that of reported biliary adenofibroma. Despite lengthy discussion, an appropriate pathological diagnosis could not be found among the current classifications of biliary tumor. The tumor was finally diagnosed as unclassified multicystic biliary tumor with adenofibroma features.  相似文献   
998.
After assessing cell viability (CV), tissue-engineered constructs are often discarded, as current CV assays commonly require specific (fluorescent) dyes to stain cells and may need scaffold/tissue digestion before quantifying the live and dead cells. Here, we demonstrate and evaluate how cellular auto-fluorescence can be exploited to facilitate a noninvasive CV estimation in three-dimensional scaffolds using two advanced microscopy methods. Mixtures of live and dead C2C12 myoblasts (0%, 25%, 50%, 75%, and 100% live cells) were prepared, and CV was determined before seeding cells into collagen carriers using the trypan blue (TB) assay. Cell-seeded collagen gels ([CSCGs], n=5/cell mixture) were produced by mixing collagen solution with the live/dead cell mixtures (7×10(6) cells/mL). After polymerization, two-photon microscopy (TPM) and confocal microscopy images of the CSCG were acquired (n=30 images/CSCG). It was found that live and dead cells systematically emit auto-fluorescent light with different spectral characteristics. Viable cells showed predominantly blue fluorescence with a peak emission around 470?nm, whereas dead cells appeared to mainly emit green fluorescent light with a peak intensity around 560?nm. For TPM, live and dead cells were distinguished spectrally. For confocal images, the intensity ratio of images taken with band-pass filters was used to distinguish live from dead cells. CV values obtained with both TPM and confocal imaging did not significantly differ from those acquired with the established TB method. In comparison to TPM, confocal microscopy was found to be less accurate in assessing the exact CV in constructs containing mostly live or dead cells. In summary, monitoring cellular auto-fluorescence using advanced microscopy techniques allows CV assessment requiring no additional dyes and/or scaffold digestion and, thus, may be especially suitable for tissue-engineering studies where CV is measured at multiple time points.  相似文献   
999.
1000.
Dermal papilla cells (DPCs) interact with epithelial stem cells and induce hair folliculogenesis. Cell-based therapies using expanded DPCs for hair regeneration have been unsuccessful in humans. Two major challenges remain: first, expanded DPCs obtained from adult hair follicles have functional limitations; second, a clinically applicable method is needed for transplanting DPCs. This study aimed to identify an efficient, minimally invasive and economical DPC transplantation procedure for use in clinical settings. Five clinically applicable transplantation procedures were tested, termed the Pinhole, Laser, Slit, Non-vascularized sandwich (NVS) and Hemi-vascularized sandwich (HVS) methods. Labelled rat dermal papilla tissue was transplanted into rat sole skin, and hair follicle regeneration was evaluated histologically. Regenerated follicles and labelled DPCs were detected for all methods, although some follicles showed abnormal growth, i.e. a cystic or inverted appearance. The HVS method, pioneered here, resulted in significantly larger number of regenerated follicles that were more mature and regular than those observed using the other methods. Moreover, hair growth was detected after expanded adult-derived DPC transplantation using the HVS method. These results suggest that direct contact of epithelial and dermal components and better vascularization/oxygenation of the recipient site are critical for hair regeneration in cell-based therapies.  相似文献   
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