高-低氧放疗在晚期腹盆腔肿瘤治疗中的应用及价值

目的探讨高-低氧放疗在晚期腹盆腔肿瘤姑息治疗中的价值。方法60例晚期腹盆腔肿瘤患者分为高-低氧放疗组和普通放疗组,每组30例,比较放疗后两组的副反应及生存质量、生存时间。结果放疗后高-低氧组白细胞减少较普通组轻(P<0.05),两组血红蛋白和血小板减少无明显差异(P>0.05);急性腹泻发生率高-低氧组低于普通组(P<0.05);生存质量改善及生存时间,高-低氧组优于普通组(P<0.05)。结论在晚期腹盆腔肿瘤的姑息治疗中,高-低氧放疗优于普通放疗。

高-低氧放疗在子宫内膜癌中的应用及临床观察

目的探讨高-低氧放疗在子宫内膜癌姑息治疗中的价值。方法 80例晚期子宫内膜癌患者分为高-低氧放疗组和普通放疗组,每组40例,比较放疗后两组的副反应、生存质量和生存时间。结果放疗后高-低氧组的白细胞减少,较普通组轻(P<0.05),两组血红蛋白和血小板的减少无明显差异(P>0.05);生存质量及生存时间,高-低氧组优于普通组(P<0.05)。结论在子宫内膜癌的姑息治疗中,高-低氧放疗优于普通放疗。

高-低氧放疗临床应用的可行性探讨(附10例报告)

目的探讨高-低氧放疗在临床应用中的可行性并初步评价其疗效及副作用。方法健康成年志愿者18例,检测其吸入不同浓度氧后生命体征(心率、呼吸、血压、血氧饱和度及心电图)的变化及耐受性。观察10例晚期、有腹部或盆腔复发或转移包块的恶性肿瘤病人在行高-低氧放疗时的耐受性,初步评价高-低氧放疗的有效率及副作用。结果健康成年志愿者吸入不同浓度氧后的主要生命体征无显著变化,10例病人在接受高-低氧放疗时未出现不能耐受的不良反应。结论对于具备适应证的病人,应用高-低氧放疗是安全的,具有一定的可行性。

高-低氧放疗对乳腺癌术后患者心肌保护的临床研究

目的:探讨高-低氧放疗对乳腺癌术后患者的心肌保护作用。方法:乳腺癌改良根治手术后患者60例,分为高-低氧放疗组和常规放疗组,每组30例,比较两组患者放疗前和不同放疗剂量下血清肌钙蛋白T(cTnT)的浓度和阳性率变化。结果:放疗剂量达到30Gy时两组患者血清cTnT浓度均显著增高(P<0.05);放疗剂量达到50Gy时高-低氧放疗组血清cTnT浓度和阳性率显著低于常规放疗组(P<0.05)。结论:cTnT动态变化是评价放射性心肌损伤的较好指标,高-低氧放疗对乳腺癌术后患者心肌有较好的保护作用。

高-低氧双向诱导制备新生大鼠支气管肺发育不良并发肺动脉高压模型

目的通过高-低氧双向诱导方法,建立新生大鼠支气管肺发育不良(BPD)并发肺动脉高压(PH)模型。方法将足月新生SD大鼠随机分为4组,A组(21%O2)、H组(60%O2)、AL组(13%O2)和HL组(60%~13%O2),分别于生后7 d和14 d进行超声心动图检查,计算右心室射血时间/肺动脉加速时间(RVET/PAAT)比值;于生后14 d进行肺功能测定;留取肺组织及心脏标本,测定右心室湿质量/(左心室+室间隔湿质量)比值;对肺组织切片进行HE染色,α-平滑肌肌动蛋白(α-SMA)免疫组织化学染色和弹性蛋白染色并评估。结果生后14 d HL组RVET/PAAT比值较A组明显升高;肺功能测定结果显示,HL组组织阻力及弹性阻力显著升高;肺组织切片可见肺泡化进程受阻;α-SMA,Elastin表达及分布均发生改变。结论应用60%~13%高-低氧双向诱导方法建立的大鼠模型,不仅符合经典BPD病理表现,同时形成了PH,与传统BPD模型相比,更适合临床早产儿BPD并发PH的相关研究。

高-低氧全肺照射对小鼠肺纤维化的影响

目的以小鼠肺组织中ＴＧＦβ１含量变化为指标，观测高低氧（ＨＯ＋ＬＯ）照射对肺晚期损伤的生物学效应。方法雄性Ｃ５７ＢＬ小鼠，１３Ｇｙ全肺一次照射，照射同时分别吸入空气、高氧（９５％Ｏ２＋５％ＣＯ２）或高低氧（１０％Ｏ２＋５％ＣＯ２＋８５％Ｎ２），照射后不同时间取肺组织ＨＥ染色、Ｍａｓｏｎ染色、Ｖ．Ｇ．染色观察肺纤维化形成。ＲＴＰＣＲ方法测定肺组织内ＴＧＦβ１的表达。结果照射后８个月肺组织局部灶性纤维化形成。高氧组肺纤维化面积大于空气组及ＨＯ＋ＬＯ组，两者相比，差异具有显著性；ＨＯ＋ＬＯ组纤维化面积虽略高于空气组，但差异无显著性。照射后３６小时，ＴＧＦβ１表达下降，照射后２个月，ＴＧＦβ１表达升高，至照射后８个月，略呈下降趋势，但仍高于正常对照。结论低氧的加入降低单纯高氧导致的正常组织损伤，ＨＯ＋ＬＯ照射不增加肺的晚期损伤。

吸入高-低氧对动物学习记忆能力的影响

目的探讨高低氧（ｈｉｇｈｃｏｎｃｅｎｔｒａｔｉｏｎｏｘｙｇｅｎ＋ｌｏｗｃｏｎｃｅｎｔｒａｔｉｏｎｏｘｙｇｅｎ，ＨＯ＋ＬＯ）放射治疗临床应用的可行性。方法跳台法检测昆明鼠吸入ＨＯ＋ＬＯ后，学习及记忆能力的影响。结果一次性吸入ＨＯ＋ＬＯ后１２，３６小时检测未见异常；连续吸入ＨＯ＋ＬＯ（每日１次，最长２０天）后２４，４８小时检测未见异常。结论呼吸ＨＯ＋ＬＯ对小鼠学习、记忆能力无影响。ＨＯ＋ＬＯ放射治疗具有临床应用的安全性和可行性。

缺氧诱导因子氧感知信号通路与“高氧-低氧悖论”的研究进展

氧稳态对细胞功能的维持至关重要,缺氧诱导因子(HIF)氧感知信号通路在氧浓度调节及氧稳态维持中发挥了十分重要的作用。高氧至常氧、常氧至低氧的变换会使细胞处于相对缺氧状态,可触发通常由缺氧引发的细胞内级联反应,增强细胞对抗缺氧的能力,这种现象被称为“高氧-低氧悖论”(HHP),其机制与HHP诱导HIF-1α表达上调有关。本文就HIF氧感知信号通路与HHP的研究进展进行综述。

高压氧疗法治疗脑缺血的相关机制

脑缺血是指大脑各部分血液供应不足导致脑组织缺血缺氧,进而导致密集缺血区脑组织出现不可逆的损伤坏死,其高致残率、高死亡率会对患者及其家庭造成严重的伤害。在脑缺血发生后,及时采取一定的治疗措施控制梗死灶的大小,并挽救半暗带中的细胞是脑缺血预后的关键。高压氧疗法是针对脑缺血的一种潜在治疗方法,在近年来得到了越来越广泛的关注和研究,本文旨在综述近年来国内外关于高压氧疗法治疗脑缺血的相关机制及研究进展,为脑缺血患者的治疗和预后提供新思路。

Liraglutide reduces oxidized LDL-induced oxidative stress and fatty degen- eration in Raw 264.7 cells involving the AMPK/SREBP1 pathway

Baekgound Recent studies have suggested a potential role for liraglutide in the prevention and stabilization ofatherosclerotic vascular disease. However, the molecular mechanisms underlying the effect of liraglutide on atherosclerosis have not been well elucidated. The pur- pose of this study was to examine whether liraglutide protects against oxidative stress and fatty degeneration via modulation of AMP-activated protein kinase （AMPK）/sterol regulatory element binding transcription factor 1 （SREBP1） signaling pathway in foam ceils. Methods Mouse macrophages Raw264.7 cells were exposed to oxidized low density lipoprotein （oxLDL） to induce the formation of foam cells. The cells were incubated with oxLDL （50 μg/mL）, liraglutide （0.1, 0.5, 1 and 2 nmol/L） or exendin-3 （9-39） （1, 10 and 100 nmol/L） alone, or in combination. Oil Red O staining was used to detect intracellular lipid droplets. The levels of TG and cholesterol were measured using the commercial kits. Oxidative stress was determined by measuring intracellular reactive oxygen species （ROS）, malondialdehyde （MDA） and superoxide dismutase 1 （SOD）. Western blot analysis was used to examine the expression of AMPKal, SREBP1, phosphory- lated AMPKal, phosphorylated SREBP1, glucagon-like peptide-1 （GLP-1） and GLP-1 receptor （GLP-1R）. Results Oil Red O staining showed that the cytoplasmic lipid droplet accumulation was visibly decreased in foam cells by treatment with liraglutide. The TG and cholesterol content in the liraglutide-treated foam cells was significantly decreased. In addition, foam ceils manifested an impaired oxidative stress following liraglutide treatment, as evidenced by increased SOD, and decreased ROS and MDA. However, these effects of liraglutide on foam cells were attenuated by the use of GLP-IR antagonist exendin-3 （9-39）. Furthermore, we found that the expression level of AMPKa 1 and phosphorylated AMPKct 1 was significantly increased while the expression level of SREBP 1 and phosphorylated SREBP 1 was significantly decreased in foam cells following treatment with liraglutide. Conclusions This study for the first time demonstrated that the effect of liraglutide on reducing oxidative stress and fatty degeneration in oxLDL-induced Raw264.7 cells is accompanied by the alteration of AMPK/SREBP1 pathway. This study provided a potential molecular mechanism for the effect of liraglutide on reducing oxidative stress and fatty degeneration.

Microstructure and isothermal oxidation of 3Al_2O_3·2SiO_2/SiC coating on high and low density carbon-carbon composites

Carbon-carbon composite （C/C） materials are prone to severe oxidation and volatilization problems. To address these issues, mullite （3Al2O3.2SiO2）/silicon carbide （SIC） coatings were deposited on C/C composite substrates characterized into high and low densities. The coatings were applied by a two-step approach： pack cementation and silica sol based slurry coating processes. The relationship between the microstructure of 3Al2O3·2SiO2/SiC coatings and C/C substrates during isothermal oxidation cycle at 1 500 ℃ was investigated using X-ray diffractometer （XRD） and scanning electron microscope （SEM） mounted with energy dispersive spectrometer （EDS）. The results indicate that the density of the substrates has a marked effect on the coatings. Dense, thick and well-bonded coatings are obtained in the high density substrate. After 106 h of isothermal oxidation, the high density substrate with 3Al2O3-2SiO2/SiC coating offers effective protection as compared to low density substrate suffering recession.

A successful mountain rescue operation in Yushu Earthquake

On April 14, 2010, an earthquake reaching 7.1 Richter scale struck Jiegu Town of Yushu. More than 2 698 people were confirmed dead, and 12 135 were injured, of which 1 434 were severely injured. Rescue operation was carried out soon after the disaster; however, the rescue teams face great challenges of altitude hypoxia, freezing temperature and very bad weather. Thus, 1 434 severe injuries were rapidly transported airlifted to hospitals in Xining and neighboring provinces for effective treatment. The extremity trauma （49.9 % ） was the most common patteru of injuries. Asphyxia （40.8 % ） was by far the most important reason for death. A high incidence of acute altitude illness in the lowland rescuers was a special medical problem during the highest earthquake in Yushu. We have learned more lessons from Yushu Earthquake.

A necklace of pearl in high altitude medicine and hypoxic physiology in Yushu Earthquake

During Yushu Earthquake,a large number of rescuers flocked to the mountainous quake areas. Under such a very specific circumstance,a high incidence of acute altitude illness was observed in rescuers who rapidly traveled from near sea level to an altitude of 4 000 m. It is evident that acute altitude illness leads to a significant human and economic toll,and also seriously influences the mountain rescue operation. So what does this teach us about mountain rescue in Yushu? Professor Wu Tianyi and many other authors collected shining points of the experiences and drew the lessons from the Yushu Earthquake into this special issue in Engineering Sciences which is like to thread pearl beads for a necklace. What readers learn from this special issue will have implications for the health and well-being of all high altitude populations all over the world.

Carbon nanotubes loaded with vanadium oxide for reduction NO with NH_3 at low temperature

The catalytic activity of carbon nanotubes-supported vanadium oxide(V_2O_5/CNTs) catalysts in the selective catalytic reduction(SCR) of NO with NH_3 at low temperatures(<250℃) was investigated.The effects of V_2O_5loading,reaction temperature,and presence of SO_2 on the SCR activity were evaluated.The results show that V_2O_5/CNTs catalysts exhibit high activity for NO reduction with NH_3 at low-temperatures.The catalysts also show very high stability in the presence of SO_2.More interestingly,their activities are significantly promoted instead of being poisoned by SO_2.The promoting effect of SO_2 is distinctly associated with V_2O_5 loading,particularly maximized at low V_2O_5 loading,which indicated the role of CNTs support in this effect.The promoting effect of SO_2 at low temperatures suggests that V_2O_5/CNTs catalysts are promising catalytic materials for low-temperature SCR reactions.

Structure Characterization of Fluorosilicone Oils

Fluorosilicone oil is polysiloxane with alkyl side chains containing fluorine, and because of its excellent thermal oxidation stability, cold flow property and cryogenic property, it can be widely used as a high temperature lubricant in the field of military aerospace industry. Two kinds of fluorosilicone oils, FSiO-a and FSiO-b, were synthesized by different pro- cessing means. FTICR MS was used to collect the information on composition and structure of the two polymers, respec- tively. The test results show that the two fluorosilicone oils have different contents of fluorine-containing chain segments (m/ n value), the maximum distribution of m/n value of FSiO-a oil ranges from 0.22 to 0.25, and that of FSiO-b oil ranges from 0.4 to 0.67. Difference in synthesis techniques makes this discrepancy and affects the quality and thermal stability of the fluoro- silicone oils.

Clinical application of full automatic animal experimental cabin of normobaric/hypobaric hypoxia and high carbon dioxide

To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobaric hypoxic and high carbon dioxide environment. Methods： Sixty SPF-class male DS rats were divided into 2 groups, 20 for normobaric, hypoxic conditions and the other 40 for hypobaric, hypoxic conditions. For each group, the pulmonary arterial pressure and carotid arterial pressure indicators of rats were examined by using the physiological multi-detector, and the pulmonary vascular changes in the structure were observed. Results： The normobaric/hypobaric hypoxic with high carbon dioxide environment can promote the formation of pulmonary hypertension and accelerate changes in pulmonary vascular remodeling, and promote the right ventricular hypertrophy. Conclusion： Clinical applications showed that the animal experimental cabin has observed and controlled accurately. The result was safe, reliable and reproducible. The cabin can successfully establish the pulmonary hypertension model in normobaric/hypobaric hypoxic with high carbon dioxide environment, and in order to study the physiological mechanism of a variety of circulation and respiratory diseases caused by lack of oxygen, which provided an experimental technology platform for clinical research.

Clinical Application of the Full Automatic Animal Experimental Cabin of Normobaric/Hypobaric Hypoxia and High Carbon Dioxide

Objective： To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobarie hypoxic and high carbon dioxide environment. Methods： 60 SPF-class male SD rats were divided into two groups, 20 for normobaric, hypoxie conditions and the other 40 for hypobarie, hypoxic conditions. For each group, we examined the pulmonary arterial pressure and carotid arterial pressure indicators of rats by using the physiological muhi-detector measurement, and observed the pulmonary vascular changes in the structure. Results： The normobaric/hypobarie hypoxic with high carbon dioxide environment can promote the formation of pulmonary hypertension and accelerate changes in pulmonary vascular remodeling, and promote the right ventricular hypertrophy. Conclusion： Clinical applications showed that the animal experimental cabin has observed and controlled accurately. The result was safe, reliable and reproducible. The cabin can successfully establish the pulmonary hypertension model in normobaric/hypobaric hypoxie with high carbon dioxide enviromnent, and in order to study the physiological mechanism of a variety of circulation and respiratory diseases caused by lack of oxygen, which provided an experimental technology platform tor clinical research.

Quercetin,the key constituent of Astragali Radix,modulates ferroptosis in PASMCs and attenuates hypoxia pulmonary hypertension via the MAPK signaling pathway

This study delved into the mechanism by which the principal component of Astragali Radix regulated ferroptosis in the context of hypoxia-induced pulmonary hypertension,employing a combination of network pharmacology and experimental validation techniques.Active constituents of Astragali Radix and their corresponding targets were identified using the TCMSP database,while therapeutic targets associated with hypoxia-induced pulmonary hypertension were sourced from the GeneCards database.The Venn online tool facilitated the identification of overlapping targets between the active constituents of Astragali Radix and hypoxia-induced pulmonary hypertension.Interaction network diagrams depicting the relationship between Astragali Radix’s active constituents and their targets were constructed using Cytoscape software,with core targets and sub-networks identified using the CytoHubba plug-in.Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were conducted using the DAVID database.Additionally,the FerrDb database was consulted to analyze genes implicated in regulating ferroptosis.The investigation revealed 18 active constituents selected from Astragali Radix,with quercetin emerging as the key component.A total of 35 potential targets associated with Astragali Radix in regulating ferroptosis and addressing hypoxia-induced pulmonary hypertension were predicted.Experimental validation demonstrated that quercetin could inhibit the MAPK signaling pathway,resulting in reduced Fe2+and lipid peroxide levels,increased GPX4 expression,and the reversal of ferroptosis.In summary,this study elucidated the fundamental constituents and pivotal signaling pathways through which Astragali Radix modulated ferroptosis and mitigated hypoxia-induced pulmonary hypertension.Specifically,quercetin,a core constituent of Astragali Radix,was observed to inhibit ferroptosis in pulmonary arterial smooth muscle cells via the MAPK pathway and alleviate hypoxia-induced pulmonary hypertension.

Air-promoted selective hydrogenation of phenol to cyclohexanone at low temperature over Pd-based nanocatalysts

Attaining high activity with high selectivity at low temperature is challenging in the selective hydrogenation of phenol to cyclohexanone due to its high activation energy （Ea, 55-70 kJ/mol）. Here we report a simple and efficient strategy for phenol hydrogenation catalyzed by Pd in aqueous phase at 30 ℃ by introducing air to promote the catalysis. With the assistance of air, 〉99% conversion and 〉99% selectivity were achieved over Pd（111）/Al2O3 with an overall turnover frequency （TOF） of 621 h-1, -80 times greater than that of the state-of-art Pd catalyst at 30 ℃. Mechanism studies revealed that phenol was activated to generate phenoxyl radicals. The radicals were yielded from the reaction between phenol and hydroxyl radicals in the presence of hydrogen, oxygen and protic solvent on Pd. The phenoxyl pathway resulted in a low apparent Ea （8.2 kJ/mol） and thus high activity. More importantly, this strategy of activating substrate by air can be adapted to other Pd based catalysts, offering a new thinking for the rational design of cyclohexanone production in industry.