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41.
Lingling Wang Lujing Wu Zhouting Zhu Qiong Zhang Wanyu Li Gwendolyn Michelle Gonzalez Yinsheng Wang Tariq M Rana 《The EMBO journal》2023,42(2)
Adenosine N6‐methylation (m6A) and N6,2′‐O‐dimethylation (m6Am) are regulatory modifications of eukaryotic mRNAs. m6Am formation is catalyzed by the methyl transferase phosphorylated CTD‐interacting factor 1 (PCIF1); however, the pathophysiological functions of this RNA modification and PCIF1 in cancers are unclear. Here, we show that PCIF1 expression is upregulated in colorectal cancer (CRC) and negatively correlates with patient survival. CRISPR/Cas9‐mediated depletion of PCIF1 in human CRC cells leads to loss of cell migration, invasion, and colony formation in vitro and loss of tumor growth in athymic mice. Pcif1 knockout in murine CRC cells inhibits tumor growth in immunocompetent mice and enhances the effects of anti‐PD‐1 antibody treatment by decreasing intratumoral TGF‐β levels and increasing intratumoral IFN‐γ, TNF‐α levels, and tumor‐infiltrating natural killer cells. We further show that PCIF1 modulates CRC growth and response to anti‐PD‐1 in a context‐dependent mechanism with PCIF1 directly targeting FOS, IFITM3, and STAT1 via m6Am modifications. PCIF1 stabilizes FOS mRNA, which in turn leads to FOS‐dependent TGF‐β regulation and tumor growth. While during immunotherapy, Pcif1‐Fos‐TGF‐β, as well as Pcif1‐Stat1/Ifitm3‐IFN‐γ axes, contributes to the resistance of anti‐PD‐1 therapy. Collectively, our findings reveal a role of PCIF1 in promoting CRC tumorigenesis and resistance to anti‐PD‐1 therapy, supporting that the combination of PCIF1 inhibition with anti‐PD‐1 treatment is a potential therapeutic strategy to enhance CRC response to immunotherapy. Finally, we developed a lipid nanoparticles (LNPs) and chemically modified small interfering RNAs (CMsiRNAs)‐based strategy to silence PCIF1 in vivo and found that this treatment significantly reduced tumor growth in mice. Our results therefore provide a proof‐of‐concept for tumor growth suppression using LNP‐CMsiRNA to silence target genes in cancer. 相似文献
42.
观察神经梅毒的临床特点,以提高对神经梅毒的诊断与治疗水平。回顾性分析哈尔滨医科大学附属第一医院2005年1月至2010年12月收治的23例神经梅毒患者的临床资料。神经梅毒患者男17例(73.9%),女6例(26.1%),男女比约为2.8∶1;年龄27~71岁,平均年龄43.1岁。本组首发症状:麻痹性痴呆(7例)、精神异常(3例)、急性脑梗死(3例)、癫痫(2例)、脊髓病变(2例)、颅高压(2例)、周围神经损害(2例)、脑神经损害(1例)、无症状性神经梅毒(1例)。23例患者血清及脑脊液快速血浆反应素实验及梅毒螺旋体血凝试验均呈阳性反应。颅脑电子计算机断层扫描(CT)和/或磁共振成像(MRI)检查多表现为额叶、顶叶、颞叶、基底节等多发病变。本组患者经大剂量青霉素治疗后病情有显著改善20例,死亡1例,自动出院2例。神经梅毒的临床表现复杂多样,神经系统各部位均可受累,诊断依靠病史及临床表现、实验室血清及脑脊液梅毒抗体检测,误诊率高,应早期诊断,诊断后应进行规范治疗,早期治疗效果较好。 相似文献
43.
Treatment of Biogas Produced in Anaerobic Reactors for Domestic Wastewater: Odor Control and Energy/Resource Recovery 总被引:1,自引:0,他引:1
Adalberto Noyola Juan Manuel Morgan-Sagastume Jorge E. López-Hernández 《Reviews in Environmental Science and Biotechnology》2006,5(1):93-114
Anaerobic municipal wastewater treatment in developing countries has important potential applications considering their huge
lack of sanitation infrastructure and their advantageous climatic conditions. At present, among the obstacles that this technology
encounters, odor control and biogas utilization or disposal should be properly addressed. In fact, in most of small and medium
size anaerobic municipal treatment plants, biogas is just vented, transferring pollution from water to the atmosphere, contributing
to the greenhouse gas inventory. Anaerobic municipal sewage treatment should not be considered as an energy producer, unless
a significant wastewater flow is treated. In these cases, more than half of the methane produced is dissolved and lost in
the effluent so yield values will be between 0.08 and 0.18 N m3 CH4/kg COD removed. Diverse technologies for odor control and biogas cleaning are currently available. High pollutant concentrations
may be treated with physical-chemical methods, while biological processes are used mainly for odor control to prevent negative
impacts on the treatment facilities or nearby areas. In general terms, biogas treatment is accomplished by physico-chemical
methods, scrubbing being extensively used for H2S and CO2 removal. However, dilution (venting) has been an extensive disposal method in some small- and medium-size anaerobic plants
treating municipal wastewaters. Simple technologies, such as biofilters, should be developed in order to avoid this practice,
matching with the simplicity of anaerobic wastewater treatment processes. In any case, design and specification of biogas
handling system should consider safety standards. Resource recovery can be added to anaerobic sewage treatment if methane
is used as electron donor for denitrification and nitrogen control purposes. This would result in a reduction of operational
cost and in an additional advantage for the application of anaerobic sewage treatment. In developing countries, biogas conversion
to energy may apply for the clean development mechanism (CDM) of the Kyoto Protocol. This would increase the economic feasibility
of the project through the marketing of certified emission reductions (CERs). 相似文献
44.
45.
肉桂酰辅酶A还原酶(cinnamoyl-CoA reductase,CCR)是木质素合成代谢的关键酶。该研究以菊芋(Helianthus tuberosus L.)‘廊芋8号’为材料,克隆到1个菊芋的CCR基因,命名为HtCCR1(GenBank登录号为MN205540),其开放阅读框(ORF)长975bp,编码324个氨基酸,其中含有FR_SDR_e保守结构域。系统进化分析表明,HtCCR1与向日葵CCR蛋白(XP_021989763.1)共聚于一支,二者亲缘关系最近。实时定量PCR分析表明,HtCCR1基因在菊芋茎和叶中的表达量显著高于在根和块茎中;盐(150mmol·L-1 NaCl)胁迫处理6、12和24h后,处理组HtCCR1基因的表达量均显著高于对照组;干旱(20%PEG6000)胁迫6和12h后,处理组HtCCR1基因的表达较对照组均显著上调。成功构建pET-28a-HtCCR1原核表达载体,转化大肠杆菌BL21(DE3)并诱导出了符合预期大小的蛋白,表明HtCCR1重组蛋白已成功表达。该研究结果为进一步研究HtCCR1基因的功能及利用基因工程手段调节菊芋中木质素的生物合成奠定了基础。 相似文献
46.
47.
An off-line filtering ditch–pond system was designed and constructed to control the small point and runoff pollution at the Wuhan City Zoo, Hubei Province, China. The quantity and quality of wastewater discharge and runoff from 16 rainfall events were measured to test the effectiveness of the off-line treatment train. The results showed that the water quality was improved and high retention rates for water and pollutants were also achieved by the off-line treatment train. In the outflows, the event mean concentrations (EMCs) of TSS, COD, TN, TDN, TP and TDP were reduced by 75%, 50%, 50%, 57%, 74% and 80% compared to the inflows. In 2005, the annual inflow volume in the catchment was 6783 m3 and the water retention rate was 80.1%. The retention rates in the annual loads of TSS, COD, TN and TP came to 86.4%, 85.5%, 83.9% and 82.9%, respectively. Therefore, the off-line filtering ditch–pond system was shown to be an effective and economical measure to control diffuse pollution. It would be worthwhile to extend the off-line treatment train to regions with limited land resources, especially in urban areas. 相似文献
48.
Michel A. Paul James C. Miller Ryan J. Love Harris Lieberman Sofi Blazeski Josephine Arendt 《Chronobiology international》2013,30(5):867-890
Jet lag degrades performance and operational readiness of recently deployed military personnel and other travelers. The objective of the studies reported here was to determine, using a narrow bandwidth light tower (500 nm), the optimum timing of light treatment to hasten adaptive circadian phase advance and delay. Three counterbalanced treatment order, repeated measures studies were conducted to compare melatonin suppression and phase shift across multiple light treatment timings. In Experiment 1, 14 normal healthy volunteers (8 men/6 women) aged 34.9±8.2 yrs (mean±SD) underwent light treatment at the following times: A) 06:00 to 07:00 h, B) 05:30 to 07:30 h, and C) 09:00 to 10:00 h (active control). In Experiment 2, 13 normal healthy subjects (7 men/6 women) aged 35.6±6.9 yrs, underwent light treatment at each of the following times: A) 06:00 to 07:00 h, B) 07:00 to 08:00 h, C) 08:00 to 09:00 h, and a no-light control session (D) from 07:00 to 08:00 h. In Experiment 3, 10 normal healthy subjects (6 men/4 women) aged 37.0±7.7 yrs underwent light treatment at the following times: A) 02:00 to 03:00 h, B) 02:30 to 03:30 h, and C) 03:00 to 04:00 h, with a no-light control (D) from 02:30 to 03:30 h. Dim light melatonin onset (DLMO) was established by two methods: when salivary melatonin levels exceeded a 1.0 pg/ml threshold, and when salivary melatonin levels exceeded three times the 0.9 pg/ml sensitivity of the radioimmunoasssy. Using the 1.0 pg/ml DLMO, significant phase advances were found in Experiment 1 for conditions A (p?<?.028) and B (p?<?0.004). Experiment 2 showed significant phase advances in conditions A (p?<?0.018) and B (p?<?0.003) but not C (p?<?0.23), relative to condition D. In Experiment 3, only condition B (p?<?0.035) provided a significant phase delay relative to condition D. Similar but generally smaller phase shifts were found with the 2.7 pg/ml DLMO method. This threshold was used to analyze phase shifts against circadian time of the start of light treatment for all three experiments. The best fit curve applied to these data (R2?=?0.94) provided a partial phase-response curve with maximum advance at approximately 9–11 h and maximum delay at approximately 5–6 h following DLMO. These data suggest largest phase advances will result when light treatment is started between 06:00 and 08:00 h, and greatest phase delays will result from light treatment started between 02:00 to 03:00 h in entrained subjects with a regular sleep wake cycle (23:00 to 07:00 h). 相似文献
49.
A loam soil from Pennsylvania without a history of exposure to explosives was incubated with 5 g kg-1 of 15N-labeled 2,4,6-trinitrotoluene (TNT) and 200 μCi kg-1 of 14C-TNT for 3 days and then amended with compost at a 1:2 soil to compost ratio. The compost was prepared by mixing 40% alfalfa hay, 40% grass hay, 10% spent mushroom compost, and 10% municipal biosolids. The mixture of soil and compost was inoculated with methanogens from cattle manure, amended with glucose and starch, and incubated for 37 days under anaerobic conditions. The anaerobic incubation was followed by 26 days of forced aerobic incubation. At the end of the aerobic phase, most of the radioactivity was associated with organic matter; only 8.7% could be extracted with water and methanol, but no TNT was present in the extracts as determined by high-performance liquid chromatography. The unextractable radioactivity was associated with humic acid (40.0±1.0%), fulvic acid (14.3±1.4%), and humin (28.2±0.5%). Radioactive materials associated with humic acid and humin were analyzed by solid-state 15N-nuclear magnetic resonance (NMR) spectrometry. The NMR spectra indicated that nitro groups of TNT had been reduced to amino groups thatwere subsequently involved in the formation of covalent bonds with soil organic matter. 相似文献
50.
目的:评价导管接触溶栓与机械辅助吸栓治疗急性髂股静脉血栓的临床效果。方法:回顾性分析162例急性下肢深静脉血栓(髂股静脉血栓)形成患者临床资料,其中导管溶栓治疗组(A组)80例、机械辅助吸栓组(B组)82例,比较两组患者治疗后患肢深静脉溶栓率、消肿率、并发症发生率、治疗时间的差异。结果:急性下肢髂股静脉血栓溶栓率B组(46.45±11.56)%显著高于A组(32.05±10.7)%(P0.05)。患肢消肿率B组(68.68±10.75)%和A组(41.34±11.26)%有明显统计学差异(P0.05)。两组并发症发生率无明显统计学意义。两组溶栓时间A组明显长于B组,两组间比较有明显统计学差异。结论:机械辅助吸栓治疗急性髂股静脉血栓早期疗效好于导管接触溶栓。 相似文献