N-乙酰半胱氨酸对脑死亡状态巴马小型猪肾脏结构、功能与核转录因子κB表达的影响

目的：观察核转录因子κB活性抑制剂N-乙酰半胱氨酸对脑死亡状态下巴马小型猪肾脏结构、功能与核转录因子κB mRNA其蛋白表达的影响，以期提高脑死亡供肾的肾移植效果。方法：实验于2003—08／2004—12在河南省实验动物中心及河南省病理学重点实验室完成。①实验分组及方法：将15只巴马小型猪按随机数字表法分为3组（n=5），即脑死亡组、N-乙酰半胱氨酸组及对照组。脑死亡组和N-乙酰半胱氨酸组均应用改进的缓慢间断颅内加压法建立脑死亡模型，脑死亡组不行药物干预；N-乙酰半胱氨酸组分别于初次确认脑死亡后1h，12h给予N-乙酰半胱氨酸。对照组动物麻醉后仅行开颅与开关腹手术。②实验评估：分别于首次判定脑死亡后3，6，12，18和24h检测动物血清中尿素氮、肌酐、白细胞介素1β、白细胞介素6、肿瘤坏死因子α水平。于脑死亡后3，6，12及24h开腹取相同部位肾组织，苏木精-伊红染色后观察肾组织结构变化，应用免疫组化染色观察核转录因子κB蛋白的表达水平，应用反转录-聚合酶链反应法检测核转录因子κB mRNA动态变化。结果：15只猪均进入结果分析。①自首次判定脑死亡后12h开始，脑死亡组和N-乙酰半胱氨酸组尿素氮和肌酐水平逐渐升高（P〈0．05），相同时间点比较N-乙酰半胱氨酸组显著低于脑死亡组（P〈0．05）。②自首次判定脑死亡3h开始，脑死亡组及N-乙酰半胱氨酸组白细胞介素1β、白细胞介素6、肿瘤坏死因子α逐渐升高（P〈0．05），相同时间点比较N-乙酰半胱氨酸组显著低于脑死亡组（P〈0．05）。③自脑死亡后3h开始，脑死亡组及N-乙酰半胱氨酸组肾组织NF-κB mRNA其蛋白表达水平逐渐升高（P〈0．05），相同时间点比较N-乙酰半胱氨酸组显著低于脑死亡组（P〈0．05）。④N-乙酰半胱氨酸组和脑死亡组动物脑死亡后12h可见肾脏结构变化，N-乙酰半胱氨酸组变化程度明显轻于脑死亡组。结论：N-乙酰半胱氨酸可能通过抑制核转录因子κB mRNA其蛋白的表达，减少炎症介质的释放，从而保护脑死亡状态下肾脏的功能及结构，提高脑死亡供肾肾移植效果。     

Markers of HIV infection in the Concorde trial. Concorde Co-ordinating Committee

The Concorde trial compared immediate (Imm) with deferred (Def) AZT monotherapy in asymptomatic HIV-positive participants. Haematological and immunological markers and weight were measured throughout, and correlated with clinical endpoints. Markers associated with disease progression (CD4 lymphocyte count and percentage, platelets, p24 antigen and beta 2 microglobulin favoured Imm: those associated with toxicity (haemoglobin, neutrophils and white cell count) favoured Def. CD8 and total lymphocyte count did not differ significantly between groups. In multivariate analysis, the combination of baseline CD4, p24 antigen and beta 2m was the best baseline predictor of disease. Including change in CD4 and beta 2m at 12 weeks, or changes over follow- up in these markers significantly improved the fit. Markers were also incorporated into the definition of 'clinical' endpoints. Hazard ratio estimates from end-points that included CD4 < 50 and CD4 < 25 were closest to those for AIDS or death alone, but added very few extra events. Use of other landmark CD4 counts (100 or greater) or relative decreases in counts (25% or more) increased the number of events, but overestimated the effect of immediate AZT. Although AZT had a beneficial effect on the surrogate markers of efficacy evaluated, these changes did not predict clinical outcome, nor could the markers be usefully incorporated into an endpoint definition.      

Long-term use of antecubital veins for plasma exchange. The Canadian Cooperative Multiple Sclerosis Study Group

True or sham plasma exchange was done weekly for 20 weeks in patients in two of the randomization groups in a prospective, blind clinical trial of experimental treatments for multiple sclerosis. Because patients could be randomized to receive sham plasma exchange and placebo medications, it was decided when the trial was designed that the use of fistulae, arteriovenous shunts, venous cutdowns, or other aggressive forms of venous access would not be permitted for any patient. Accordingly, patients judged to have inadequate superficial antecubital veins were ineligible for the trial. To date, only 13 (4.4%) of 294 patients considered for entry into the trial have been rejected on these grounds. In only 4 of the 93 patients undergoing exchange was it necessary to discontinue plasma exchange because of inadequate venous access. In 79.3 percent of the 1207 exchanges done in these patients, there were no problems of any kind with venous access. In 5.4 percent of these 1207 exchanges, it was necessary to terminate the procedure prematurely because of difficulties with patients' veins. Thus, the great majority of patients free of serious systemic illness (other than chronic progressive multiple sclerosis) can undergo weekly plasma exchange for up to 20 weeks using superficial antecubital veins without the need to resort to more invasive methods of venous access.     

人工耳蜗植入术后声场主观测听阈值与产生听觉最小电流值的关联分析

目的:观察人工耳蜗植入术后产生听觉的最小电流值(T值)和声场主观测听阈值的变化趋势,分析可能存在的对应关系。方法:于2001-01/2004-12选择解放军第四军医大学西京医院全军耳鼻咽喉专科中心收治的接受人工耳蜗植入者20例,年龄3～6岁,无耳蜗畸形,植入后电极阻抗测试完全正常。植入者在开机后的3,6,12个月3个时间点调机和声场测听。人工耳蜗调试采用澳大利亚Cochlear公司提供的调试软件R126 V2.1,采用游戏行为测听法确定T值。对开机后3,6,12个月的声场主观测听阈值与人工耳蜗调试中T值的变化进行分析。结果:声场测听阈值在开机12个月中呈逐渐降低趋势,开机12个月时声场测听的听力水平较3个月和6个月有明显提高(P<0.05)。植入者术后12个月声场主观测听(啭音)听阈为15～35dB nHL,听力水平较术前有明显提高。20例植入者T值在开机12个月后降到144～158mA,明显低于6个月和3个月的水平(P<0.05)。结论:开机后12个月内产生听觉的最小电流值和声场测听阈值都呈逐渐下降趋势。植入者在熟悉适应了电声信号后,可以在刺激电流强度下降的同时获得更好的听力水平。     

The effect of donor red cell sedimentation rate on efficiency of granulocyte collection by centrifugal leukapheresis

BACKGROUND: Granulocyte collection relies on the use of a red cell- sedimenting agent and is influenced by poorly defined intrinsic donor characteristics. The donor's baseline red cell (erythrocyte) sedimentation rate (ESR), a readily measurable intrinsic donor variable, may influence the effectiveness of red cell-sedimenting agents and affect the granulocyte yield. STUDY DESIGN AND METHODS: The in vitro and in vivo effects of 6-percent hydroxyethyl starch on the donor ESR were prospectively studied in 67 granulocytapheresis procedures with a blood cell separator, and the findings were correlated with granulocyte collection efficiency (GCE). A relationship that predicts the GCE on the basis of the donor ESR was then derived and tested. RESULTS: The 3.7-fold mean increase in the donor ESR measured after in vitro addition of hydroxyethyl starch approximated the 3.3-fold increase measured when it was administered to the donors. Higher baseline ESR correlated with larger in vitro and in vivo hydroxyethyl starch-induced increases in ESR and predicted more efficient cell collections and greater cell yields. Furthermore, both ESR and GCE, which varied significantly among donors, remained constant for a given donor undergoing repeat procedures. The results could be summarized by a simple predictive formula that relates the GCE (%) to the ESR (mm/hour): GCE = 1.3ESR + 45. The GCE and yield as predicted by the formula were accurate within 10 percent of the observed values in six subsequent procedures. CONCLUSION: In granulocyte harvests using a blood cell separator with hydroxyethyl starch as the sedimenting agent, 1) both ESR and GCE vary widely among donors yet may remain relatively constant for a given donor; 2) the baseline ESR correlates with hydroxyethyl starch-modified ESR and with GCE; and 3) it may be possible to predict GCE and yield from the donor's baseline ESR.     

'Localized amyloidosis': 123I-labelled SAP component scintigraphy and labial salivary gland biopsy

In apparently localized amyloidosis, there is no appropriate test to determine whether systemic deposits exist. We studied the value of serum amyloid P component (SAP) scintigraphy and labial salivary gland (LSG) biopsy on patients with apparently localized amyloidosis in 12 patients who had neither clinical nor biological evidence of systemic amyloidosis. All patients had an LSG biopsy and echocardiography. Iodine-123-labelled serum amyloid P component (123I-SAP) scintigraphy was performed in all patients. Whole-body scintigraphy was done, and tissue retention was evaluated at 24 h and 48 h. Of these 12 patients, three had amyloidosis in their LSG and had abnormal 123I-SAP scintigraphy; these three had a secondary clinical history of systemic amyloidosis. Three other patients had abnormal 123I-SAP scintigraphy without detectable systemic amyloid deposits, but one had a previous history of bilateral carpal tunnel syndrome treated with infiltration. 123I-SAP scintigraphy in association with LSG biopsy may be helpful in determining the localized or systemic character of amyloid disease.      

Is technology the best medicine? Three practice theoretical perspectives on medication administration technologies in nursing

Even though it is often presumed that the use of technology like medication administration technology is both safer and more effective, the importance of nurses' know‐how is not to be underestimated. In this article, we accordingly try to argue that nurses' labor, including their different forms of knowledge, must play a crucial role in the development, implementation and use of medication administration technology. Using three different theoretical perspectives (‘heuristic lenses') and integrating this with our own ethnographic research, we will explore how nursing practices change through the use of medication technology. Ultimately, we will argue that ignoring (institutional) complexity and the various types of important knowledge that nurses have, will seriously complicate the implementation of medication administration technology.     

Open-access transvaginal sonography in women of reproductive age with abnormal vaginal bleeding: a descriptive study in general practice

Background

Diagnostic ultrasonography is used by GPs in approximately 10% of patients of reproductive age with abnormal vaginal bleeding. Transvaginal sonography is recommended as a first-line diagnostic instrument for assessing uterine pathology.

Aim

To assess if findings resulting from openaccess sonography were in agreement with the GPs’ working hypotheses and if these findings contributed to GPs’ management.

Design and setting

Prospective observational cohort study of GPs working in the health district of the Academic Medical Center, Amsterdam and their patients consulting with abnormal vaginal bleeding.

Method

Data on patients’ history, GPs’ primary working hypotheses, and intended management were recorded. After sonography, GPs recorded their actual management.

Results

A total of 122 patients were included by 18 GPs from June 2003 to December 2004. Data from 89 patients were available for analysis. The GPs’ working hypotheses implied ‘no structural pathology’ in 65/89 patients, and ‘fibroids’ in 24/89 patients. Sonographic findings were confirmed in 50/65 patients where ‘no structural pathology’, and in 14/24 of those where ‘fibroids’ were expected. Initially, GPs had intended to refer nine patients to a gynaecologist. Actual management after sonographic assessment was watchful waiting or drug therapy in 57/89 patients. Eighty-nine per cent of these patients had normal sonographic findings. The actual referral rate rose to 27/89 patients. In 17 referred patients, sonographic findings were suggestive of intracavitary abnormalities.

Conclusion

Open-access sonography contributed to more accurate diagnoses and improved GPs’ management of women with abnormal vaginal bleeding.