Reverse Iodine Transfer Polymerization (RITP) of 1,1,2,2‐Tetrahydroperfluorodecyl Acrylate in Supercritical Carbon Dioxide

Reverse iodine transfer polymerization (RITP) of 1,1,2,2‐tetrahydroperfluorodecyl acrylate (FDA) is successfully performed in supercritical carbon dioxide (scCO₂) at 70 °C under a CO₂ pressure of 300 bar. PolyFDA (PFDA) of increasing molecular weights (from 10 000 to 100 000 g mol^?1) is synthesized with good agreement between theoretical, ¹H NMR spectroscopy and and size exclusion chromatography/refractive index/right‐angle laser‐light scattering/differential viscometer (SEC/RI/RALLS/DV)‐estimated molecular weights (). Furthermore, the increase of goes with a decrease of the dispersity of the polymers (? from 2.06 to 1.33), which is consistent with a controlled radical polymerization (CRP). Lastly, the structure of final PFDA and therefore the RITP process are confirmed by matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) analyses.

     

Facilitation of ventricular tachyarrhythmia induction by isoproterenol

Ventricular tachyarrhythmia induction was facilitated during infusion of isoproterenol in 21 of 60 patients with ventricular tachycardia (VT) or ventricular fibrillation (VF) in whom programmed electrical stimulation alone failed to reproducibly induce sustained ventricular tachyarrhythmias. Of 44 patients with no ventricular tachyarrhythmias induced before isoproterenol infusion, 11 had a sustained ventricular tachyarrhythmia and 1 patient had unsustained VT induced by isoproterenol alone or by programmed stimulation during the infusion. In 9 of 16 patients in whom nonreproducible or unsustained ventricular tachyarrhythmias were induced before isoproterenol infusion, more reproducible or more sustained ventricular tachyarrhythmias were induced during the infusion. Tachyarrhythmia induction was facilitated by isoproterenol in 20 of 40 patients with sustained VT clinically, but in only 1 of 20 patients with unsustained VT or VF clinically. Among patients with sustained VT clinically, those with exercise-provoked VT and those who had not been tested with stimulation at a second right ventricular site or in the left ventricle were more likely to have induction facilitated by isoproterenol. Drugs effective against induction of isoproterenol-facilitated ventricular tachyarrhythmias were identified in 13 of 25 trials. These drugs were effective during a mean follow-up of 17 months in 7 of 9 long-term trials.     

Left ventricular function at high altitude examined by systolic time intervals and M-mode echocardiography

To better understand the effects of high-altitude hypoxia on cardiac performance, healthy lowlandresiding volunteers were studied in 2 groups: 10 subjects after acute ascent to 12,500 ft (3,810 m) (acute group) and 9 subjects after chronic exposure for 6 weeks to 17,600 ft (5,365 m) and 11,000 ft (3,353 m) (chronic group). Systolic time intervals and M-mode echocardiograms were recorded at low and high altitudes. Heart rate was 21% greater at high altitude for all subjects. Preejection period/left ventricular ejection time (PEP/LVET) increased by 16% in the acute group and by 22% in the chronic group. Heart size was smaller at high altitude in both groups, with left atrial and left ventricular (LV) diameters decreasing by 10 to 12%. These changes were statistically significant (p ≤ 0.01). Despite the increase in PEP/LVET, echocardiographic measurements of LV function (percent fractional shortening and mean normalized velocity of circumferential fiber shortening) remained normal. LV isovolumic contraction time was shorter at high altitude, suggesting heightened, rather than depressed, contractility. LV function does not appear to deteriorate at high altitude. Alterations in systolic time intervals probably result from decreased preload, as reflected by smaller heart size, rather than from heart failure or depressed LV contractility.     

食盐加碘对轻度缺碘地区甲状腺功能亢进症患者住院率的影响

目的 了解常州市区全民食盐加碘(USI)后甲状腺功能亢进症(甲亢)患者住院率的变化情况。方法 采用回顾性调查方法收集常州市区医院1992—1999年甲亢患者住院情况，计算住院率并进行比较。结果 甲亢患者年住院率在实行USI策略后，呈现逐年上升趋势。结论 甲亢患者住院率的升高可能与全民食盐加碘有关，2000年食盐加碘策略的调整是及时、正确的，应进一步对2000年以后的甲亢患者住院情况进行调查。     

碘代谢检测指标评估甲状腺疾病手术治疗患者碘营养状况的价值

目的探讨碘代谢检测指标在甲状腺疾病手术治疗患者碘营养状况评估中的应用价值。方法收集31名健康志愿者和30例甲状腺疾病手术患者术前、术后血清、晨尿和24 h尿标本,应用电感耦合等离子体质谱法检测样本中的碘浓度,比较健康者和患者术前、术后血清碘、晨尿碘、晨尿碘/晨尿肌酐、24 h尿碘和24 h尿碘排泄量的差异,并分析健康者碘代谢检测指标的测定值对世界卫生组织、美国梅奥医学中心和奎斯特诊断公司提供的参考范围的验证率。结果甲状腺疾病术前组的晨尿碘/晨尿肌酐比值显著低于健康对照组(P<0.05),两组其他指标的差异无统计学意义(P均>0.05);患者经手术治疗后血清碘、晨尿碘和24 h尿碘水平均显著高于术前水平(P<0.05);健康对照组各项碘代谢指标的中位数均在3个实验室提供的参考范围内,但仅有血清碘、晨尿碘及41~70岁人群的晨尿碘/晨尿肌酐比值与美国梅奥医学中心提供的参考范围的验证率大于90%;晨尿碘/晨尿肌酐比值的受试者工作特征曲线下面积最大,为0.737。结论晨尿碘/晨尿肌酐比值可能用于甲状腺疾病手术治疗患者碘营养状况的评估。     

The effect of pharmacological PI3Kγ inhibitor on eotaxin-induced human eosinophil functions

BackgroundAsthma is characterized by chronic inflammation caused by activation of immune cells including Th2 lymphocytes and eosinophils. Phosphoinositide 3-kinase (PI3K) γ deficient asthmatic mice did not develop lung eosinophilia, although the detailed mechanisms are not well known. A CC chemokine eotaxin (CCL11) plays a prominent role in developing eosinophilic inflammation through CCR3. In this study, we tested the roles of PI3Kγ in eotaxin-induced eosinophil functions using a pharmacological inhibitor.MethodHuman peripheral blood eosinophils were isolated by CD16-negative selection method. The effect of AS605240, synthetic PI3Kγ inhibitor on eotaxin-induced adhesion, chemotaxis, and degranulation were studied using intracellular adhesion molecule-1 (ICAM-1)-coated plates, Boyden chamber system, ELISA for eosinophil-derived neurotoxin (EDN) levels in the culture supernatant, respectively. CCR3 expression levels and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation were assessed by flowcytometry. Involvement of PI3Kγ in spontaneous apoptosis was studied using flowcytometry.ResultsAlthough AS605240 did not affect the eosinophil spontaneous apoptosis, eotaxin-induced chemotaxis, adhesion to ICAM-1 coated plate, and EDN release were inhibited by AS605240. AS605240 also inhibited the eotaxin-induced ERK1/2 phosphorylation without down-regulation of surface CCR3 expression.ConclusionThese results indicate that PI3Kγ inhibitor attenuates eotaxin-induced eosinophil functions by suppressing the downstream signaling of CCR3 without significant cytotoxicity. PI3Kγ plays an important role in the development of eosinophilic inflammation and blockade of PI3Kγ might be a therapeutic strategy for treatment of eosinophil-related diseases including asthma.     

The Effects of Oxygen Functional Groups on Graphene Oxide on the Efficient Adsorption of Radioactive Iodine

Oxygen-containing functional groups tend to induce a strong interaction between solid adsorbents and iodine molecules, yet have not been systematically investigated. Herein, on the basis of a series of nitric acid-treated graphene oxide (GO) with different contents of oxygen functional groups for iodine adsorption, it was found that the iodine uptake capacity is proportionate to the oxygen content and the diversities of oxygen-containing groups. The density functional theory (DFT) calculation results also suggest that oxygen-containing groups result in strong interactions between iodine molecules and the adsorbents through a covalent bond-forming process, among which -OH groups possess a higher adsorption energy averagely. Such theoretical and experimental work deepens our understanding of the effects of oxygen functional groups on iodine adsorption and provides novel ideas for future design and synthesis of high-performance solid adsorbents for radioactive iodine.