家犬气管插管纯氧通气7h后肺超微结构的变化

目的:观察家犬气管插管后连续纯氧通气7h肺超微结构的变化。方法:实验于1999-07/2000-01在青岛大学医学院附属医院动物实验中心完成。健康杂种犬20只,随机数字法分为纯氧机械通气组(吸入氧浓度=100%,n=10)及34%氧浓度机械通气组(吸入氧浓度=34%,n=10)。氯胺酮肌肉注射行基础麻醉,开放静脉通路,应用喉镜经口气管内插管,插管后芬太尼、潘库溴铵静脉注射,然后接BIRD8400STi呼吸机机械控制呼吸,纯氧机械通气组设定吸入氧浓度100%,34%氧浓度机械通气组设定吸入氧浓度34%。预设4个参数:潮气量10～15mL/kg,呼吸频率15～16次/min,吸呼比为1∶2,气道峰压<2.5kPa。两组均于气管插管后经股动脉切开插管测量平均动脉压和心率。气管插管期间平均每小时追加芬太尼2.0～3.0μg/kg、潘库溴铵0.1～0.15mg/kg,并酌情给予地西泮4～6mg/kg维持麻醉。实验过程中静脉持续输注生理盐水100mL/h,以补充犬血容量。分别于气管插管后1,3,5及7h监测平均动脉压、心率,用Ohmeda5250RGM麻醉气体监测仪监测吸入氧浓度、呼气末二氧化碳分压、呼吸频率及呼吸道峰压。呼吸机机械控制呼吸7h后,均取右肺下叶两三块1mm3肺组织块,用戊二醛固定,做超薄切片,枸橼酸铅染色,在电镜下观察肺组织的超微结构变化。结果:①两组犬一般资料基本相同,各时点平均动脉压、呼气末二氧化碳分压、呼吸道峰压及心率差异无显著性(P>0.05)。②电镜观察到,纯氧机械通气组50%标本线粒体肿胀、排列紊乱,基质变浅,出现透明区,双层膜变薄,少数线粒体嵴断裂或消失,有空泡样改变;40%标本可观察到Ⅰ型肺上皮细胞有吞饮增强、破坏,Ⅱ型肺泡上皮的微绒毛减少;40%标本内皮细胞吞饮增强;60%标本肺泡隔间质水肿;50%标本多形核白细胞血管内聚集或游出血管外现象;1只(10%)还观察到Ⅱ型肺泡上皮板层小体排空。而34%氧浓度机械通气组90%线粒体双层膜较完整,基质致密呈细颗粒状,Ⅱ型肺泡上皮的微绒毛正常;10%标本可观察到Ⅰ型肺上皮细胞有吞饮增强、破坏及内皮细胞吞饮增强;20%标本肺泡隔间质水肿;未见到多形核白细胞血管内聚集或游出血管外现象及Ⅱ型肺泡上皮板层小体排空。纯氧机械通气组观察到的肺超微结构的肺损伤重于34%氧浓度机械通气组。结论:纯氧通气7h后观察到的肺超微结构损伤较多,吸入氧浓度34%则相对较少,建议长时间气管插管通气时,宜降低吸入氧浓度,尽可能减少潜在的氧毒性肺损伤。     

人外周血树突状细胞的分离与鉴定

目的:体外分离培养并鉴定人外周血树突状细胞,并观察其抗原呈递功能。方法:实验于2005-05/2006-11在南方医科大学南方医院肿瘤中心生物治疗实验室完成。从人类白细胞抗原A2表达阳性的健康人外周血中分离获得单个核细胞。培养5h后洗涤贴壁细胞,加入含有10%人AB血清的RPMI1640培养基,及重组人粒细胞-巨噬细胞集落刺激因子和重组人白细胞介素4,于培养的第1,3,6天对树突状细胞的形态、表型进行分析,并定期检测树突状细胞的纯度与得率。抽取与以上树突状细胞不同来源的其他健康人外周血。经淋巴细胞分离液分离后,获取非贴壁细胞,用含10%人AB血清的1640培养基重悬,加入白细胞介素2继续孵育6d,作为同种异体T淋巴细胞。将树突状细胞分为两组,一组按常规方法培养6d,另一组在培养至第5天时加入黑色素瘤抗原基因A3编码的多肽继续培养24h。在经紫外线处理后的96孔板中,分别加入树突状细胞悬液1×104,5×103,2×103,1×103细胞/每孔,以自身T淋巴细胞作为对照,每孔设3个复孔,分别加入1×105淋巴细胞/每孔。评价树突状细胞刺激T淋巴细胞增殖的能力。结果:①单个核细胞体外培养至第6天,可获得大量、90.81%高纯度的树突状细胞,能够较高地表达21.8?1a、99.0%HLA-DR、63.4?80、18.9?83和80.6?86。②将诱导培养6d获得的两组树突状细胞作为刺激细胞,以不同的浓度与同种异体淋巴细胞混合,均可产生增殖反应;经过黑色素瘤抗原基因A3编码的多肽处理的各种比例的树突状细胞,较相应未经黑色素瘤抗原基因A3编码的多肽处理的树突状细胞激发淋巴细胞增殖的能力明显增强,浓度相对较高的树突状细胞刺激效果最明显,能够强烈地激发同种混合淋巴细胞增殖。结论:得到了一群较高程度表达CD83、CD86和HLA-DR分子、体外可强烈激发同种异体T淋巴细胞增殖的树突状细胞群。     

The effects of milk protein concentrate on the symptoms of osteoarthritis in adults: an exploratory, randomized, double-blind, placebo-controlled trial

Background: Reconstituted hyperimmune milk product has been shown to have anti-inflammatory qualities, prompting further research into its use for the relief of osteoarthritis symptoms. A concentrated form of this milk product, milk protein concentrate (MPC), contains the high-molecular-weight and low-molecular-weight components present in the reconstituted milk product.Objective: The purpose of this exploratory study was to assess the effects of MPC on the symptoms of osteoarthritis in adults.Methods: Patients aged ≥19 years with physician-diagnosed osteoarthritis with daily joint pain, stiffness, and immobility were eligible. This was a prospective, randomized, double-blind, placebo-controlled trial lasting 6 weeks and having 3 treatment arms: MPC 2000 mg BID, glucosamine sulfate 500 mg TID, and placebo. Osteoarthritis symptoms were assessed using the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index.Results: Forty-two participants were enrolled (8 men, 34 women; mean age, 59 years [range, 34-86 years]); 35 patients (5 men, 30 women) completed the study. Due to significant baseline differences in 3 (stiffness, activities, and total) of the 4 (pain, stiffness, activities, and total) WOMAC Osteoarthritis Index scores in the placebo group compared with the MPC- and glucosamine sulfate—treated groups (P ≤ 0.05), the results of this study were restricted to the analysis of intragroup performance from baseline to the completion of the study. The results showed significant improvement from baseline to week 6 for the MPC-treated group for all 4 scores (P ≤ 0.005). In the glucosamine sulfate—treated group, a significant improvement was found in stiffness and total WOMAC Osteoarthritis Index scores from baseline to week 6 (P ≤ 0.05 for both) but not in the pain or activities scores. In the placebo group, no significant changes were found in any of the WOMAC Osteoarthritis Index scores.Conclusion: The results of this study indicate that MPC, when given at a dose of 2000 mg BID, was effective in relieving the symptoms of osteoarthritis, including joint pain, joint stiffness, and immobility, in this patient population.     

The prevalence of immunization to Duffy antigens in a population of known racial distribution

A retrospective study at our hospital determined the race or ethnicity of patients seen in an 8-year period who had formed antibodies to Duffy antigens. During that time, 9876 serologic investigations had been performed as a result of a positive direct or indirect antiglobulin test. Among these samples, sera from 45 previously transfused or pregnant patients contained anti-Fya and two contained anti-Fy3. Twenty-nine of the sera that contained anti-Fya (62%) were from blacks, 12 (25%) were from whites, and 6 (13%) were from Hispanics. Both examples of anti-Fy3 were made by black patients. Red cells (RBCs) from 21 of the black patients were Fy(a-b-), those from 7 were Fy(a-b+), and those from 1 could not be phenotyped. RBCs from 17 of the non-black patients were Fy(a-b+) and those from 1 could not be phenotyped. The population of transfused patients evaluated in this study was 47 percent black, 29 percent white, and 24 percent Hispanic. Calculations based on an expected Fy(a-) frequency of 88 percent in blacks, 33 percent in whites, and 20 percent in Hispanics predict that the racial makeup of the Fy(a-) population at our hospital would be 73 percent black, 18 percent white, and 9 percent Hispanic, which is not significantly different (p = 0.25) from the racial makeup of the patients forming anti-Fya and -Fy3. These data indicate that blacks make antibodies to Duffy antigens as frequently as non-blacks.     

Viral load is a negative predictor of antioxidant levels in hepatitis C patients

The pathogenesis of chronic hepatitis C (HCV) infection is not fully known, but oxidative stress may play a role. The aim of this study was to assess the relationship between HCV load and antioxidant status among patients with chronic HCV infection. Among 23 patients, HCV load, as well as plasma beta-carotene, retinol, ascorbic acid and alpha-tocopherol were measured. Plasma retinol, ascorbic acid and alpha-tocopherol were low in 17%, 26% and 4% of the patients, respectively. Plasma ascorbic acid and alpha-tocopherol declined 9.7 micromol/l (95% CI 3.3-16.2) and 4.5 micromol/l (95% CI 2.1-7.0), respectively, and plasma beta-carotene declined by a factor of 0.60 (95% CI 0.37-0.98) per log increase in viral load. Smoking was independently associated with 8.9 micromol/l (95% CI 4.1-13.7), lower levels of plasma alpha-tocopherol and with 0.27 (95% CI 0.11-0.71) times lower plasma beta-carotene. The effect on plasma ascorbic acid was not significant (-9.2 micromol/l, 95% CI - 21.9-3.5). The association may reflect consumption of antioxidants due to HCV, although effects of low antioxidant status on viral replication cannot be excluded.     

Dairy Product Intake and Long-Term Risk for Frailty among French Elderly Community Dwellers

Dairy products (DP) are part of a food group that may contribute to the prevention of physical frailty. We aimed to investigate DP exposure, including total DP, milk, fresh DP and cheese, and their cross-sectional and prospective associations with physical frailty in community-dwelling older adults. The cross-sectional analysis was carried out on 1490 participants from the Three-City Bordeaux cohort. The 10-year frailty risk was examined in 823 initially non-frail participants. A food frequency questionnaire was used to assess DP exposure. Physical frailty was defined as the presence of at least 3 out of 5 criteria of the frailty phenotype: weight loss, exhaustion, slowness, weakness, and low physical activity. Among others, diet quality and protein intake were considered as confounders. The baseline mean age of participants was 74.1 y and 61% were females. Frailty prevalence and incidence were 4.2% and 18.2%, respectively. No significant associations were observed between consumption of total DP or DP sub-types and frailty prevalence or incidence (OR = 1.40, 95%CI 0.65–3.01 and OR = 1.75, 95%CI 0.42–1.32, for a total DP consumption >4 times/d, respectively). Despite the absence of beneficial associations of higher DP consumption on frailty, older adults are encouraged to follow the national recommendations regarding DP.     

血管成形术和支架辅助血管成形术治疗颅内动脉粥样硬化的报告标准（上）

背景和目的颅内动脉粥样硬化可造成众多患者发生缺血性卒中。过去10年间血管内治疗技术已经取得突破性进展,能够开展颅内动脉粥样硬化性狭窄的血管内治疗。采用血管成形术和支架辅助阻管成形术治疗颅内动脉粥样硬化性狭窄的患者例数不断增加。但是鉴于目前血管成形术和支架辅助血管成形术治疗狭窄性和闭塞性颅内动脉粥样硬化仍缺乏普遍认可的临床和放射学评估以及皿管内治疗技术及预后的规范,此文就是提供该方面报告标准、术语和书面定义的共识性建议。报告摘要报告标准是在技术评价委员会、神经介入外科学会、介入放射学会、美国神经外科医师协会和神经外科医师代表大会的脑血管外科分会、美国神经科学会的卒中和介入神经病学分会的联合写作组共同起草完成。对1997年1月-2007年12月间,美国国立图书馆医学文献数据库（PubMed）进行计算机检索,旨在确定已发表的狭窄性颅内动脉粥样硬化的神经介入治疗中,能用作质量评价基准的资料。我们尽可能地确定影响神经介入治疗成功及并发症可能性的危险调节变量。对狭窄性和闭塞性颅内动脉粥样硬化进行麻管内治疗的临床试验设计中,不同临床和技术问题可能影响血管内治疗的疗效,此文章为这些问题提供相关的理论基础。该指南中包括对血管内治疗试验报告标准的建议。虽然制定规范和标准主要是出于研究用途,但是这也将有助于临床实践,还适用于所有相关的出版物。结论总之,报告标准提出的建议将有助于构建有效的研究数据库,同时促进产生科学可靠的研究结果,使相似研究之间或内部能够进行可靠的比较。存某些情况下,为报告和出版的一致性,本文中的定义可能是写作组专家的共识性建议。这些建议将促使不同研究组的结果具有直接可比性。     

Maternal Temperature Elevation and Occiput Posterior Position at Birth Among Low‐Risk Women Receiving Epidural Analgesia

Introduction: To evaluate the relationship between maternal temperature elevation and occiput posterior position at birth as well as the association of fetal head position and temperature elevation on method of birth among women receiving epidural analgesia. Methods: We conducted a secondary analysis of data from the Fetal Orientation during Childbirth by Ultrasound Study (FOCUS), which used serial ultrasounds to evaluate the effect of epidural anesthesia on fetal position at birth in low‐risk women. The current analysis was limited to the 1428 study participants who received epidural analgesia. Results: In our population, 47% (n = 669) of women had a maximum intrapartum temperature greater than or equal to 99.6°F (37.6°C). The prevalence of fetal occiput posterior position at admission did not differ between women who later developed temperature elevations (24.4%) and those who did not (23.6%, P= .70). Women who developed an elevated temperature greater than or equal to 99.6°F (37.6°C) had an increased risk of occiput posterior fetal head position at birth regardless of the amount of temperature elevation (odds ratio [OR]= 2.0; 95% confidence interval [CI], 1.5‐2.8); the association persisted after control for potentially confounding factors (adjusted OR = 1.5; 95% CI, 1.1‐2.1). The cesarean birth rate among women with both temperature elevation and occiput posterior position at birth was more than 12 times the rate of women with neither risk factor (adjusted OR = 12.6; 95% CI, 7.5‐21.2). Discussion: Intrapartum temperature elevation among women receiving epidural analgesia, even if only to 99.6°F (37.6°C), is associated with approximately a 2‐fold increase in the occurrence of occiput posterior fetal head position at birth. Additionally, although this observational study cannot establish causal links, our findings suggest that the relationship between epidural‐related intrapartum temperature elevation and occiput posterior position at birth could contribute to an increased cesarean birth rate among women receiving epidural analgesia for pain relief in labor.