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91.
Min-Chi Ku Susanne A. Wolf Dorota Respondek Vitali Matyash Andreas Pohlmann Sonia Waiczies Helmar Waiczies Thoralf Niendorf Michael Synowitz Rainer Glass Helmut Kettenmann 《Acta neuropathologica》2013,125(4):609-620
High-grade gliomas are the most common primary brain tumors. Their malignancy is promoted by the complex crosstalk between different cell types in the central nervous system. Microglia/brain macrophages infiltrate high-grade gliomas and contribute to their progression. To identify factors that mediate the attraction of microglia/macrophages to malignant brain tumors, we established a glioma cell encapsulation model that was applied in vivo. Mouse GL261 glioma cell line and human high-grade glioma cells were seeded into hollow fibers (HF) that allow the passage of soluble molecules but not cells. The glioma cell containing HF were implanted into one brain hemisphere and simultaneously HF with non-transformed fibroblasts (controls) were introduced into the contralateral hemisphere. Implanted mouse and human glioma- but not fibroblast-containing HF attracted microglia and up-regulated immunoreactivity for GFAP, which is a marker of astrogliosis. In this study, we identified GDNF as an important factor for microglial attraction: (1) GL261 and human glioma cells secret GDNF, (2) reduced GDNF production by siRNA in GL261 in mouse glioma cells diminished attraction of microglia, (3) over-expression of GDNF in fibroblasts promoted microglia attraction in our HF assay. In vitro migration assays also showed that GDNF is a strong chemoattractant for microglia. While GDNF release from human or mouse glioma had a profound effect on microglial attraction, the glioma-induced astrogliosis was not affected. Finally, we could show that injection of GL261 mouse glioma cells with GDNF knockdown by shRNA into mouse brains resulted in reduced tumor expansion and improved survival as compared to injection of control cells. 相似文献
92.
Anush Mnoyan Myeongil Choi Dong Hyun Kim Bon-Jun Ku Hyunjoung Kim Kyung Jin Lee Ahmed S. Yasin Sungchan Nam Kyubock Lee 《RSC advances》2020,10(69):42432
Solar-to-steam generation characterized by nanostructured photothermal materials and interfacial heating is developed based on various carbon nanostructures such as graphene, reduced graphene oxide, CNT, or their combinations. However, multiple and sophisticated synthetic steps are required to generate macroscopic porosity in photothermal devices for the efficient mass transport of water and generated steam. Additionally, the fabrication of photothermal layers on a practical scale constitutes the main hurdle for real applications toward solar-driven desalination. Herein, we report on the development of highly efficient photothermal layers with a commercially available low-cost material, activated carbon (AC), by using facile filtration and spray coating methods, which lead to the generation of intraparticle porous structure without any additional processing. The AC-based photothermal layers generated 1.17 kg m−2 h−1 of steam under 1 sun, and 4.7 wt% of polyethyleneimine coating on AC enhanced steam generation by 8.5% under 1 sun, corresponding to 1.27 kg m−2 h−1 of the water evaporation rate and 85.66% of the photothermal conversion efficiency. This was due to improvements in light absorption and water uptake properties with the additional advantage of mechanical robustness. The outdoor solar-to-steam generation test with the spray-coated A4-sized photothermal layer in conjunction with the desalination test demonstrated the potential for practical desalination application with upscalability.Highly efficient photothermal layers were developed based on a commercially available low-cost material, activated carbon, which demonstrates the potential for practical desalination application with upscalability. 相似文献
93.
目的探讨连续式和跳跃式颈椎前路椎间盘切除融合术(ACDF)治疗多节段颈椎病的疗效及安全性。方法回顾性分析2013年1月-2018年12月收治的经非手术治疗无效的78例多节段颈椎病患者临床资料,其中36例采用跳跃式ACDF治疗(观察组),42例采用连续式ACDF治疗(对照组)。比较2组手术时间、术中出血量、住院时间等临床指标及并发症发生情况。记录2组C2~7活动度(ROM)、矢状位垂直距离(SVA)、T1倾斜角、植骨融合率、邻近及中间保留节段椎间盘退行性变加重率等影像学指标。采用日本骨科学会(JOA)评分及JOA评分改善率评估神经功能改善情况。结果所有手术顺利完成。所有患者随访8~19个月,中位随访时间为13个月。观察组手术时间和术中出血量明显少于对照组,差异有统计学意义(P < 0.05);2组住院时间差异无统计学意义(P > 0.05)。2组术后各随访时间点JOA评分均较术前改善,差异有统计学意义(P < 0.05),组间差异无统计学意义(P > 0.05);2组JOA评分改善率差异无统计学意义(P > 0.05)。2组术后12周C2~7 ROM较术前降低,SVA及T1倾斜角较术前增加,差异均有统计学意义(P < 0.05),组间差异无统计学意义(P > 0.05);末次随访时C2~7 ROM、SVA及T1倾斜角均较术后12周有所改善,接近术前水平。2组植骨融合率、邻近及中间节段椎间盘退行性变加重率比较,差异无统计学意义(P > 0.05)。2组植骨融合率、邻近及中间节段椎间盘退行性变加重率差异无统计学意义(P > 0.05)。观察组术后发生吞咽困难2例、声音嘶哑1例,并发症发生率为8.33%;对照组术后发生吞咽困难2例,并发症发生率为4.76%;组间差异无统计学意义(P > 0.05)。结论跳跃式ACDF用于经非手术治疗无效的多节段颈椎病患者可获得与连续式ACDF相近的术后疗效及安全性,并能够有效缩短手术时间,减少术中医源性创伤。 相似文献
94.
This study examined the effect of conversation and assertive skills training on social skills of schizophrenic patients. Patients who met the study criteria were randomly assigned to the experimental or control group. The experimental group received eight group training sessions and the control group received routine nursing care treatment. Data were collected at pretreatment (before group treatment), intratreatment (after fourth group treatment), posttreatment (after eighth group treatment), and follow-up (1 month after the end of group treatment). Conversation and assertive skills of the experimental group improved significantly with treatment and were superior to the control group at intratreatment, posttreatment, and follow-up. We suggest incorporating social skills training into treatment plans for patients with schizophrenia to improve their social skills ability. 相似文献
95.
The purpose of this study is to investigate the changing spectrum and clinicopathologic correlation of biopsy-proven renal diseases in central China. We retrospectively analyzed data of 4931 patients who underwent renal biopsy in ten hospitals between September 1994 and December 2014. Among them, 81.55% were primary glomerular diseases (GD), and 13.02% were secondary GD. IgA nephropathy (IgAN) was the most common primary GD (43.45%), followed by focal glomerulonephritis (16.79%), mesangial proliferative glomerulonephritis (MsPGN, 14.35%), and membranous nephropathy (MN, 13.28%). IgAN was leading primary GD in patients under 60 years old, while MN was the leading one over 60 years old. The most frequent secondary GD was lupus nephritis (LN) (47.35%). The prevalence of IgAN, MN and minimal change disease was found to increase significantly (p?<?0.001, p?<?0.001, and p?<?0.01, respectively), while that of MsPGN, membranoproliferative glomerulonephritis and LN decreased significantly (p?<?0.001, p?<?0.001, and p?<?0.05, respectively). The main indication for renal biopsy was proteinuria and hematuria (49.03%), followed by nephrotic syndrome (NS, 20.36%). IgAN was the most common cause in patients with proteinuria and hematuria, chronic-progressive kidney injury, hematuria and acute kidney injury; and MN was the leading cause of NS. Primary GD remained the predominant renal disease in central China. IgAN and LN were the most prevalent histopathologic lesions of primary and secondary GD, respectively. The spectrum of biopsy-proven renal disease had a great change in the past two decades. Proteinuria and hematuria was the main indication for renal biopsy. 相似文献
96.
97.
The phase-variable allele of the pilus glycosylation gene pglA is not strongly associated with strains of Neisseria gonorrhoeae isolated from patients with disseminated gonococcal infection 下载免费PDF全文
Power PM Ku SC Rutter K Warren MJ Limnios EA Tapsall JW Jennings MP 《Infection and immunity》2007,75(6):3202-3204
The Neisseria gonorrhoeae pglA gene has two alleles, one of which is phase variable. A previous study reported that all disseminated gonococcal infection (DGI) isolates contained the phase-variable allele and proposed a causal link. In the present study of 81 strains no absolute correlation between DGI and the phase-variable pglA allele was observed. 相似文献
98.
PURPOSE: This study aimed to evaluate the cancer detection rate in a Korean population with prostate-specific antigen (PSA) levels greater than or equal to 20.0 ng/mL. MATERIALS AND METHODS: A total of 174 men 50 to 79 years old (median 69) included in the study. The median prostate volume of the patients was 44.8 mL (range 14.1 to 210.0) and their serum PSA ranged from 20.0 to 9725.0 ng/mL (median 44.8). RESULTS: Of 174 men 141 (81.0%) were diagnosed with prostate cancer on initial biopsy. In the total number of patients, the positive predictive value (PPV) was 62.9% for PSA 20 to 29.9, 72.7% for PSA 30 to 39.9 and 100% for PSA 40 to 49.9 ng/mL. In patients with an abnormal digital rectal examination (DRE), the values for these PSA ranges increased to 89.5%, 91.7% and 100%, respectively. The PPV was 81.0% for PSA cutoff of 20, 89.2% for a cutoff of 30, 95.4% for a cutoff of 40, and 94.7% for a cutoff of 50 ng/mL. In conjunction with an abnormal DRE, the values for these PSA cutoffs increased to 95.9%, 98.1%, 100%, and 100%, respectively. CONCLUSION: Our data suggest the ability to predict the presence of prostate cancer reliably on initial biopsy when PSA threshold is greater than or equal to 50 ng/mL. This PSA threshold may be lowered to 40 ng/mL in the presence of an abnormal DRE. In Korean men with high PSA, the detection rate of prostate cancer on biopsy appears to be comparable to that for American men. 相似文献
99.
100.
新型冠状病毒(SARS-CoV-2)自2019-12爆发以来,传播速度极快,了解其流行病学特征,尤其是切断传播途径对于控制疾病传播至关重要。在传播途径的研究中,SARS-CoV-2是否通过眼表组织进行传播的问题也引起关注,但目前尚缺乏其通过眼表组织感染的临床确诊病例和实验室证据。最新研究认为SARS-CoV-2与SARS冠状病毒(SARS-CoV)属于同一种属,并且其与SARS-CoV进入细胞的途径是一样的。本文通过回顾SARS-CoV的研究,探讨SARS-CoV-2眼途径传播的可能机制。 相似文献