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31.
Chengguang Hu Yangda Song Cuirong Tang Meng Li Junwei Liu Jia Liu Minjun Liao Fuyuan Zhou Yong-Yuan Zhang Yuanping Zhou 《Clinical therapeutics》2021,43(3):572-581.e3
PurposeThe loss of serum hepatitis B surface antigen (HBsAg) in patients with chronic hepatitis B (CHB) is considered an ideal clinical outcome but rarely achieved with current standard of care. We evaluated the effectiveness in inducing HBsAg seroclearance in a real-world clinical cohort of Chinese patients with CHB treated with a combination of pegylated interferon (Peg-IFN) with tenofovir disoproxil fumarate (TDF) or monotherapy with each agent.MethodsA total of 330 patients with CHB were assigned to receive Peg-IFN plus TDF for 48 weeks (Peg-IFN plus TDF group), Peg-IFN alone for 48 weeks (Peg-IFN group), or TDF alone for 144 weeks (TDF group). The primary end point was the percentages of patients who achieved HBsAg seroclearance at week 72. Differences from the baseline characteristics and treatment data were compared using the χ2 test for categorical variables or 1-way ANOVA for continuous variables. A Kaplan–Meier test was performed to compare the HBsAg loss among the 3 groups. Discrimination of responders versus nonresponders was quantified using AUC curves. Optimal cut-offs were selected based on Youden's J statistic defined as J = sensitivity + specificity-1.FindingsAt week 72, the Kaplan–Meier cumulative HBsAg loss was 11.5% in the Peg-IFN plus TDF group, 5.7% in the Peg-IFN group, and 0% in the TDF group. The percentage of patients with HBsAg loss was comparable in the Peg-IFN plus TDF and Peg-IFN groups (P = 0.143), but both were significantly higher than that in the TDF group (P = 0.000 and P = 0.010). In addition, a significantly higher percentage of patients in the combination group and Peg-IFN group had serum HBsAg of <100 IU/mL compared with the TDF group (32.7% vs 23.6% vs 9.2%; P < 0.001) but no significant differences in the percentages of patients with HBsAg <1000 IU/mL, the undetectable serum HBV DNA and hepatitis B e antigen seroconversion. Our model predicted serum HBsAg loss at week 72 (AUC = 0.846) if the HBsAg level was reduced by > 1.5 log10 IU/mL from baseline at treatment week 24, an optimal timepoint for prediction of HBsAg loss in this cohort.ImplicationsA 48-week course of Peg-IFN and TDF combination therapy led to profound reduction in serum HBsAg level, resulting in a significantly higher rate of HBsAg loss compared with TDF monotherapy. Patients with steep HBsAg decline >1.5 log10 IU/mL at week 24 well signaled a higher probability of achieving HBsAg loss at week 72. 相似文献
32.
《Journal of biomaterials science. Polymer edition》2013,24(8):827-844
Monofilament polypropylene (PP) fibers, very similar to fibers that have been used as monofilament tailstrings of interuterinc contraceptive devices, were suspended vertically in bacterial liquid monocultures so that a portion of a fiber extended above the liquid surface. In some cases these highly oriented, cold drawn fibers were abraded prior to insertion in the cultures in order to produce surface roughness characterized by axial channels and protruding microfibrils that partially peeled from the fiber surface thereby forming the channels. Extent of migration on a fiber was assessed by aseptically cutting it into small segments, followed by culturing each segment on agar containing growth medium. Such assessment of the PP fibers after 48 h of incubation in the cultures revealed upward migration of Eschericia coli, Pseudomonas aeruginosa, and Staphylococcus aureus over significantly longer distances on the pre-roughened fibers than on those not so pre-treated. Mean measured distances of migration during 48 h were: for E. coli 2.7 ± 0.6 mm on roughened fibers (n = 16) and 0.4±0.7 mm on fibers not roughened (n = 17); for S. aureus 9.0±4.3 mm on roughened fibers (n = 13) and 0.2± 0.3 mm on fibers not roughened (n = 14); for P. aeruginosa 8.5± 3.7 mm on roughened fibers (n = 26) and 0.2± 0.5 mm on fibers not roughened (n = 5). Although no statistically significant (95% confidence level) difference could be discerned between the migration distances of S. aureus and P. aeruginosa, each of these species migrated a greater distance on the PP than did E. coli. The migrations observed are attributed predominantly to wicking of the liquid cultures upward in the axial grooves developed on the surface of the PP by the eruption and peeling of microfibrils from the surface. Surface tension of the growth medium was significantly lower than that of water and its contact angle on PP was less than 90 deg, thereby indicating a tendency to wet the PP. Bacterial growth in the medium further reduced its contact angle on PP, thereby indicating an even greater tendency to wet PP after such growth. 相似文献
33.
目的 探讨G蛋白β3亚单位C825T基因多态性与富马酸比索洛尔降压疗效的相关性。方法 选择2018-10至2020-10在解放军总医院第一医学中心心内科住院或门诊就诊的轻、中度原发性高血压患者,均口服5 mg/d比索洛尔,进行GNβ3-C825T基因型测定,依据基因型分为3组:CC组、CT组、TT组,每组150例,在3组受试者治疗7 d,1、3、6个月后进行随访,测定患者的富马酸比索洛尔药物代谢血药浓度;治疗前、治疗7 d,1、3、6个月后进行24 h动态血压监测,比较患者静息状态下收缩压及舒张压(SBP、DBP),24 h收缩压均数(24 h SBP)、24 h舒张压均数(24 h DBP)、白天收缩压均数(d SBP)、白天舒张压均数(d DBP)、夜间收缩压均数(n SBP)、夜间舒张压均数(n DBP)的组间差异;进行24 h动态心电图监测,比较24 h平均心率、窦性心律震荡水平。结果 治疗7 d,随访1、3、6个月TT组富马酸比索洛尔血药浓度均高于CC组及CT组,差异均有统计学意义(P<0.05),CC组与CT组无统计学差异,3组组内不同时间血药浓度变化均无统计学差异;应用富马酸比索洛尔后,3组患者血压均有下降趋势,其中TT组降压效果>CT组>CC组,3组间血压下降水平有统计学差异(P<0.05);治疗7 d后,动态心电图显示:3组患者心率有下降趋势,TT组>CT组>CC组,其中TT组与CT组、CC组比较有统计学差异(P<0.05),CT组与CC组心率下降无统计学差异;TT组窦性心律震荡水平优于CT组、CC组。结论 G蛋白β3亚单位C825T基因多态性与富马酸比索洛尔降压疗效之间具有相关性。 相似文献
34.
《Journal of biomaterials science. Polymer edition》2013,24(11):859-877
Blood-contacting properties of polypropylene surfaces with different crystalline states at the surface layer were examined in terms of plasma protein adsorption and changes in cytoplasmic free Ca2+ levels in platelets. Though the wettability of polypropylene surfaces was almost constantly independent from the surface layer crystallinity and interlamellar spacing, an increase in adhesiveness was observed with decreasing surface layer crystallinity and interlamellar spacing. It is suggested that the surface properties of the sheets varied in relation to the crystalline-amorphous microstructure. Minimum magnitudes in albumin and fibrinogen adsorption were observed on the polypropylene surface with a particular surface layer crystallinity (c. 55 wt%). A decrease in interlamellar spacing resulted in enhancing albumin adsorption and diminishing fibrinogen adsorption. Transient phenomena in plasma protein adsorption were observed on their surfaces with a plasma concentration. It is considered that the polypropylene surface with a particular crystalline-amorphous microstructure reduces the denaturation of adsorbed proteins. An increase in cytoplasmic free Ca2+ levels in platelets was prevented at the polypropylene surface with a surface layer crystallinity of 55 wt%: the particular crystalline-amorphous microstructure of such apolar surfaces as polypropylenes acts to reduce platelet activation. Thus, it is concluded that the blood compatibility of polypropylene surfaces is greatly improved by controlling a crystalline-amorphous microstructure at the surface layer. 相似文献
35.
《HIV clinical trials》2013,14(3):160-167
AbstractPurpose: Evaluate how reducing ritonavir (RTV) boosting from 200 mg to 100 mg once daily (QD) affects steady-state pharmacokinetics of components of a fosamprenavir (FPV)-based regimen. Methods: Prospective, open-label, pharmacokinetic study in 12 HIV-infected patients stabilized on FPV/RTV 1400 mg/200 mg + tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) 300 mg/200 mg QD (TELEX II). Pharmacokinetics were assessed by noncompartmental analysis at baseline and 4 weeks after RTV reduction to 100 mg QD. Results: Baseline median minimum plasma concentration (Cmin) and area under the plasma concentration-time curve over 24 hours post dose (AUC24h) were as follows: APV: 1,708 ng/mL, 84,260 h ? ng/mL; tenofovir: 53 ng/mL, 2,420 h ? ng/mL; FTC: 58 ng/mL, 9,190 h ? ng/mL; RTV: 80 ng/mL, 10,230 h ? ng/mL. Four weeks after reducing RTV, changes in Cmin and AUC24h were: APV: +26%, +0.6%; tenofovir: +77%, +30%; FTC: +188%, +13%; RTV –64%, –79%. Component plasma concentration ranges were consistent with historical values. Median APV Cmin was 14.7-fold above the protein-binding-adjusted 50% inhibitory concentration of wild-type HIV. Four weeks after RTV reduction, HIV-1 RNA levels remained <50 copies/mL in all patients, median CD4+ count increased from 465 to 495 cells/mm3, and favorable lipid changes and no adverse events were observed. Conclusion: Reducing RTV boosting from 200 to 100 mg QD of FPV/TDF/FTC QD conferred no detrimental effect on APV, tenofovir, FTC, or RTV pharmacokinetics and maintained virologic suppression. 相似文献
36.
目的: 建立液相色谱-质谱联用(HPLC-MS/MS)法测定人血浆中富马酸单甲酯的方法,并应用于检测中国健康受试者血浆中富马酸单甲酯的浓度。方法: 血浆样品用醋酸铵稀释后经过96孔固相萃取板前处理,以含0.5%甲酸的水溶液和甲醇作为流动相,采用梯度洗脱方式在ACE Excel 3 C18-AR(2.1 mm×50 mm)色谱柱上进行分离,每个样品分析时间为4 min。在电喷雾负电离模式下,多反应监测检测离子对m/z 129.0→m/z 85.0(富马酸单甲酯)和m/z 134.0→m/z 90.0(内标,富马酸单甲酯-d5)。结果: 富马酸单甲酯线性范围为4~1 200 ng·mL-1(r2>0.99),定量下限为4 ng·mL-1,日内和日间精密度RSD ≤ 9.7%,准确度相对偏差均在±4.2%以内,平均回收率RSD ≤ 6.6%,基质效应在98.3%~100.9%之间。稳定性实验中,各种储存条件不影响对药品浓度的准确测定。结论: 本方法运行时间短,灵敏度高,重复性好,适用于富马酸单甲酯血浆浓度定量检测。 相似文献
37.
Background
Most of the organs and tissues are preserved in formalin with its own set of disadvantages. Plastination is a unique method of permanently preserving tissue in a life like state. Plastination developed by western authorities is a labour and equipment intensive affair. Most common polymer used is S10, however this study uses easily available alternative polymers for plastination.Method
Various polymers like Epoxy resins, Polypropylene resins, Orthocryl and silicone were used in plastinating the anatomical specimens. Specific methods were used for solid, hollow organs and brain specimens. The specimens were made to undergo stages of fixation, dehydration, impregnation and curing. The results were studied and interpreted under various parameters.Results
The results were interpreted under various parameters like shrinkage, retention of colour, odour, pliability and retention of gross anatomy. The study concluded that Orthocryl and Epoxy resins retained maximum colour with minimal shrinkage while maximum discolouration was with polypropylene plastinates. Brain sections were best preserved in Orthocryl.Conclusion
The study concluded that indigenous methods and materials can produce quality plastinates which can be an important adjunct to traditional methods of teaching however more studies need to be done for refinement. 相似文献38.
39.
Emily Wible Manika Agarwal Sibel Altun Tyler Ramir Grace Viana Carla Evans Henry Lukic Spiro Megremis Phimon Atsawasuwan 《The Angle orthodontist》2019,89(3):432
Objectives:To evaluate long-term light transmittance, surface roughness, and flexural modulus of polypropylene/ethylene copolymer retainer material after exposure to different cleaning methods.Materials and Methods:Standardized polypropylene/ethylene copolymer retainer specimens (n = 70, 50.8 mm × 12.7 mm × 1.0 mm) were subjected to seven chemical cleaning solutions: Invisalign cleaning crystals, Retainer Brite, Polident, Listerine mouthwash, 2.5% acetic acid, 0.6% NaClO, and 3% H2O2 for 6 months. The specimens were exposed to the different solutions twice a week for 15 minutes or according to manufacturer''s instructions, then stored in artificial saliva at 37°C. Another group of specimens (n = 10) were brushed with a standardized toothbrushing machine for 2 minutes twice a week. At baseline and 6 months, light transmittance, surface roughness, and flexural modulus of the specimens were quantified using spectrophotometry, profilometry and three-point bend testing, respectively. Qualitative analysis was performed using a scanning electron microscope (SEM). Statistical analyses were performed at a significance level of .05.Results:The results showed that light transmittance decreased significantly from baseline for all cleaning methods at 6 months. For an individual method, no significant differences were observed between specimens at baseline and 6 months in surface roughness and flexural modulus. No discernible differences in surface features were observed on SEM images.Conclusions:The results indicate that different cleaning methods affect the long-term light transmittance of the studied polypropylene/ethylene copolymer retainer material. However, for an individual cleaning method, no significant differences were shown for surface roughness or flexural modulus values at 6-months compared to baseline. 相似文献
40.
目的探讨长期应用布地奈德福莫特罗吸入剂(160μg/4.5μg)对支气管哮喘患者的控制作用及对肾上腺皮质功能、糖脂代谢的影响。方法将78例支气管哮喘患者随机分成治疗组和对照组,治疗组给予布地奈德福莫特罗吸入剂(160μg/4.5μg),每日两次,对照组按需应用沙丁胺醇吸入剂,口服茶碱缓释片。观察周期为一年。两组患者在治疗前1天(T0)、一个月(T1)、三个月(T3)、六个月(T6)、12个月(T12),分别给予哮喘控制测试(asthma control test,ACT)评分,呼气峰流速(peak expiratory flow,PEF)日变异率检查,分别抽血测皮质醇、促肾上腺素皮质激素(ACTH),空腹血糖(FPG)、糖化血红蛋白(HbA1c)、甘油三酯、总胆固醇。结果治疗组患者ACT评分高于对照组(P0.05),治疗组患者PEF日变异率小于对照组(P0.05)。治疗组与对照组皮质醇、ACTH、FPG、HbA1c、总胆固醇、甘油三酯之间的差异无统计学意义(P0.05)。结论布地奈德福莫特罗吸入剂对支气管哮喘患者的控制有良好作用,长期应用对患者的肾上腺皮质功能、糖脂代谢无不良影响。 相似文献