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71.
Vanderson Rocha Gnès Devergie Gerard SociÉ Patricia Ribaud Hélène EspÉrou Nathalie Parquet & Eliane Gluckman 《British journal of haematology》1998,103(1):243-248
Dyskeratosis congenita (DC) is a rare inherited disorder often associated with aplastic anaemia. We report the cases of five boys transplanted with an HLA-identical related donor for severe aplastic anaemia (SAA) associated to DC; in all cases successful engraftment was observed. Three patients died 2–8 years after bone marrow transplantation (BMT) with signs of endothelial cell damage syndrome (kidney microangiopathy and liver veno-occlusive disease). Another boy died 1 year after BMT from Evans syndrome and invasive aspergillosis. One boy currently presents anaemia, polyarthritis of unknown origin, pulmonary fibrosis and gut malabsorption 7.5 years after BMT. SAA associated with DC can be successfully treated by allogeneic BMT. However, these early and late complications observed are very unusual after BMT and probably reflect the association of transplanted-related factors, evolution of the underlying disease, and increased sensitivity of endothelial cells. Modified conditioning approaches, advances in supportive care and surveillance of these unusual complications offer the possibility of improved outcome for these patients. 相似文献
72.
Using of bio-wastes in dye adsorption is one of the greenest influential applied techniques for the removal of dyestuff from the industrial effluents and it considered as waste management. In the current study, banana peel waste (BPW) was used as an inexpensive and eco-friendly adsorbent for methylene blue (MB) dye. Mechanical pretreatment of BPW was carried out and followed by biological activation using Rhizopus microspores. MB dye was adsorbed by mechanically pretreated BPW (mBPW) by 31%. Moreover, the day nine fermented BPW fibers (mbBPW) is the best time for R. microspores to complete activation, where adsorption ratio reached to about 96.5%. Likewise, enzymes activity was recorded the highest activity after this period of fermentation, where enzymes activity of cellulase, xylanase, lignin peroxidase, poly phenol oxidase and laccase were 0.75, 0.68, 0.38, 0.55 and 0.32 U/ml, respectively. The FT-IR, SEM and BET were used to observe the effect of treatment on the BPW. Otherwise, the kinetics study is illustrated that the adsorption of MB with mbBPW fitted with pseudo-first-order kinetic models. However, the adsorption parameters indicated that the Langmuir model is better to describe the adsorption of dye with excellent maximum adsorption capacity 991 mg/g. In conclusion, biologically activated BPW is very efficient for dye adsorption as well as waste management. 相似文献
73.
Christopher M. Wrobel Timothy R. Geiger Rebecca N. Nix Aaron M. Robitaille Sandra Weigand Alfredo Cervantes Miguel Gonzalez Jennifer M. Martin 《Virus research》2013
LMP-1 is a constitutively active Tumor Necrosis Factor Receptor analog encoded by Epstein–Barr virus. LMP-1 activation correlates with oligomerization and raft localization, but direct evidence of LMP-1 oligomers is limited. We report that LMP-1 forms multiple high molecular weight native LMP-1 complexes when analyzed by BN-PAGE, the largest of which are enriched in detergent resistant membranes. The largest of these high molecular weight complexes are not formed by purified LMP-1 or by loss of function LMP-1 mutants. Consistent with these results we find a dimeric form of LMP-1 that can be stabilized by disulfide crosslinking. We identify cysteine 238 in the C-terminus of LMP-1 as the crosslinked cysteine. Disulfide crosslinking occurs post-lysis but the dimer can be crosslinked in intact cells with membrane permeable crosslinkers. LMP-1/C238A retains wild type LMP-1 NF-κB activity. LMP-1's TRAF binding, raft association and oligomerization are associated with the dimeric form of LMP-1. Our results suggest the possibility that the observed dimeric species results from inter-oligomeric crosslinking of LMP-1 molecules in adjacent core LMP-1 oligomers. 相似文献
74.
none 《Journal of histotechnology》2013,36(4):357-359
AbstractToluidine blue stain has been widely used for staining undecalcified bone sections, but previous techniques required removal of embedding plastic or surface etching with both alcohol and acid solutions. In this study, solutions of toluidine blue at different pHs were used to stain unetched and acidetched sections. A group of the test staining solutions were heated in an effort to enhance section staining. Acid-etching prior to staining was found to be necessary to achieve bone matrix staining, but methanol etching could be eliminated if staining solutions were heated to 55–60°C. Sections stained with the heated solutions buffered to pH 7.0 or 8.0 had optimum morphology. (The J Histotechnol 17:357, 1994) 相似文献
75.
目的 观察415 nm蓝光联合5%过氧苯甲酰凝胶治疗轻中度寻常性痤疮的临床疗效与安全性。方法 选取武警湖北总队医院2019-03至2020-09轻中度寻常性痤疮90例,随机分为3组,每组30例。联合组同时予415 nm蓝光照射联合5%过氧苯甲酰凝胶外用;蓝光组和药物组分别予415 nm蓝光照射和5%过氧苯甲酰凝胶外用。3组均在治疗8周后判定疗效。结果 治疗8周后联合组有效率为83.3%。蓝光组和药物组有效率分别为30%和56.7%,与联合组有效率比较,差异均有统计学意义。治疗过程中不良反应少见且患者均可耐受。结论 415 nm蓝光联合5%过氧苯甲酰凝胶治疗轻中度寻常性痤疮疗效显著,不良反应少。 相似文献
76.
BackgroundThis study aimed to investigate the penetration depth of two different dyes after root canal preparation using PIPS and SWEEPS methods.Materials and methodsA total of 60 single-rooted human teeth which were extracted for periodontal reasons were collected and stored in the sterile saline until using in the study. The crowns of the teeth were cut such that the remaining piece was 12 mm long. The root canals were prepared. Teeth were divided randomly into two initial groups (n = 30): indocyanine green solution (ICG) and methylene blue solution. Then, these teeth were divided into final subgroups (n = 10): Er:YAG laser irradiation with PIPS(photon-induced photoacoustic streaming) technique, Er:YAG laser irradiation with SWEEPS(shock-wave enhanced emission photoacoustic streaming) technique, and no irradiation. The penetration depth measurements were done by the stereo microscope in three zones of each specimen.ResultsThe difference between ICG in the control group and PIPS and SWEEPS in the coronal area was not significant. In the middle section the difference between PIPS and the control group was marginally insignificant (P = 0.053). In the methylene blue group, PIPS had significantly higher penetration depth in the apical area compared to the control group (P = 0.004). In the middle section, both PIPS and SWEEPS showed significantly higher penetration than the control group.ConclusionAccording to the results of this study, the laser has the potential to increase the penetration of methylene blue. Root canal preparation with the PIPS technique can increase the dye penetration. However, the SWEEPS technique and the conventional method have a similar outcome in terms of dye penetration. 相似文献
77.
ObjectivesThis study aimed to assess the effect of photodynamic therapy (PDT) on expression of CASP3, NRAS and HRAS genes at mRNA levels, and apoptosis of head and neck squamous cell carcinoma (HNSCC) cell line.Materials and methodsIn order to complete the present in vitro study, HNSCC cell line (NCBI C196 HN5) purchased from Pasteur Institute. Cells were divided into four groups; Group 1: photodynamic treatment (laser + methylene blue (MB) as photosensitizer), group 2: MB, group 3: laser (with 660 nm wavelength), and group 4: control (without any treatment). To determine the optimal concentration of MB, in a pilot study, toxicity of MB in different concentration was assessed using MTT assay. Cells in group 1, 2 and 3 was treated at optimal concentration of MB (1.6 μg/mL). Gene expression at mRNA levels was assessed after 24 h incubation, using real-time (qRT)-PCR. The expression of BAX and BCL2 genes at the mRNA levels was analyzed to evaluate apoptosis. 2−ΔΔCt values of BCL2, BAX, CASP3, NRAS, and HRAS in groups was analyzed using ANOVA. Tukey’s HSD and Games Howell test was used to compare between two groups.ResultsOver-expression of BAX (p < 0.001), CASP3 (p < 0.001) and down-regulation of BCL2 (p = 0.004), HRAS (p = 0.023) and NRAS (p = 0.045) were noted in group 1 (PDT), compared with the control group. Treatment by laser alone induce down-regulation of CASP3 (p < 0.05), BAX (p < 0.05), BCL2 (p > 0.05), HRAS (p > 0.05) and NRAS (p > 0.05).ConclusionPDT caused down-regulation of NRAS, HRAS and BCL2 and over-expression of CASP3 and BAX genes at mRNA levels in HNSCC cell line. The present study raises the possibility that the role of MB on BCL2 down-regulation and BAX and CASP3 over-expression was higher than laser alone while it seems that laser alone was more effective than MB in HRAS and NRAS down-regulation. 相似文献
78.
Fiona C. Shenton Thomas Campbell James F. X. Jones Susan Pyner 《Journal of anatomy》2021,238(1):36-52
Cardiac reflexes originating from sensory receptors in the heart ensure blood supply to vital tissues and organs in the face of constantly changing demands. Atrial volume receptors are mechanically sensitive vagal afferents which relay to the medulla and hypothalamus, affecting vasopressin release and renal sympathetic activity. To date, two anatomically distinct sensory endings have been identified which may subserve cardiac mechanosensation: end-nets and flower-spray endings. To map the distribution of atrial receptors in the subendocardial space, we have double-labelled rat right atrial whole mounts for neurofilament heavy chain (NFH) and synaptic vesicle protein 2 (SV2) and generated high-resolution maps of the rat subendocardial neural plexus at the cavo-atrial region. In order to elucidate the nature of these fibres, double labelling with synaptophysin (SYN) and either NFH, calcitonin gene-related peptide (CGRP), choline acetyltransferase (ChAT) or tyrosine hydroxylase (TH) was performed. The findings show that subendocardial nerve nets are denser at the superior cavo-atrial junction than the mid-atrial region. Adluminal plexuses had the finest diameters and stained positively for synaptic vesicles (SV2 and SYN), CGRP and TH. These plexuses may represent sympathetic post-ganglionic fibres and/or sensory afferents. The latter are candidate substrates for type B volume receptors which are excited by stretch during atrial filling. Deeper nerve fibres appeared coarser and may be cholinergic (positive staining for ChAT). Flower-spray endings were never observed using immunohistochemistry but were delineated clearly with the intravital stain methylene blue. We suggest that differing nerve fibre structures form the basis by which atrial deformation and hence atrial filling is reflected to the brain. 相似文献
79.
80.
目的 综合评价甲苯胺蓝染色在口腔潜在恶性疾患(oral potential malignant disorders,OPMDs)及口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)早期诊断中的临床应用价值。方法 选取2016年8月至2018年5月于北京大学口腔医院口腔黏膜科就诊的OPMDs及OSCC患者533例。对所有患者进行临床检查、甲苯胺蓝染色和组织病理学检查。以组织病理学诊断为金标准,评价甲苯胺蓝染色的灵敏度、特异度和准确度;绘制受试者工作特征曲线(receiver operator characteristic curve,ROC)及计算曲线下面积(area under curve,AUC),评价甲苯胺蓝染色的诊断价值;并对上皮异常增生或OSCC的影响因素进行logistic回归分析。结果 甲苯胺蓝染色诊断上皮异常增生或OSCC的灵敏度为75.32%,特异度为84.17%,准确度为81.61%;诊断OSCC的灵敏度为97.10%,特异度为76.51%,准确度为79.17%;诊断上皮异常增生的灵敏度为57.65%,特异度为84.17%,准确度为79.31%。随着上皮异常增生程度的加重,甲苯胺蓝染色诊断的灵敏度越高;且甲苯胺蓝染色诊断轻、中度上皮异常增生的灵敏度均高于临床危险度诊断,其差异均有统计学意义(均P < 0.05)。ROC曲线分析,甲苯胺蓝染色诊断上皮异常增生或OSCC的AUC值为0.797,高于临床危险度诊断的AUC值(0.721);甲苯胺蓝染色诊断OSCC的AUC值为0.868,高于临床危险度诊断的AUC值(0.802)。logistics回归分析发现,年龄、病程、活检病损部位、临床危险度和甲苯胺蓝染色均与上皮异常增生或OSCC显著相关,甲苯胺蓝染色阳性者患有上皮异常增生或OSCC的风险是甲苯胺蓝染色阴性的13.655倍。结论 综合多项指标评估结果,甲苯胺蓝染色是一种诊断效力强的无创辅助检查技术,推荐应用于OPMDs及OSCC的早期诊断。 相似文献