Ultrasensitive analysis of the intestinal absorption and compartmentalization of aluminium in uraemic rats: a 26Al tracer study employing accelerator mass spectrometry

BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit the determination of femtogram amounts of 26Al in blood and in various tissues with good precision and free of external contamination. METHODS: In the present study we used trace quantities of 26Al to investigate the intestinal absorption and compartmentalization of aluminium in rats with renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single oral doses of 20 ng 26Al were administered to six animals in each group and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone, liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al were significantly lower in uraemic rats compared to controls, whereas urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/- 6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in uraemia. The target tissues of cellular transferrin-mediated 26Al uptake, liver and spleen, tended to show a larger degree of aluminium accumulation in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27 pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site of extracellular aluminium deposition, 26Al concentrations were more elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g). Estimated total 26Al accumulation in all measured target tissues was significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/- 7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/- 6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our data suggest that fractional absorption from a dietary level dose of 26Al is about 0.13%. Compartmentalization occurs in transferrin-dependent target tissues such as liver and spleen; however, in quantitative terms extracellular deposition in bone is more important. Uraemia has a significant effect on the intestinal absorption and compartmentalization of aluminium. It enhances fractional absorption and increases subsequent extracellular deposition of aluminium in bone. However, at the same time uraemia does not increase transferrin-dependent cellular accumulation of aluminium in liver and spleen.      

Childhood adversities as risk factors for alexithymia and other aspects of affect dysregulation in adulthood

BACKGROUND: Affect regulation is assumed to be a biologically based function that can become disrupted by inadequate parenting and by traumatic experiences. We studied the relation between the perceived parental parenting style, and sexual and physical abuse, with alexithymia, dissociation, anxiety and depression. METHODS: In a cross-sectional study psychiatric outpatients were administered a structured interview on childhood physical and sexual abuse and they completed a number of questionnaires about the parenting styles of their parents, and about alexithymia, dissociation and mood pathology. RESULTS: Maternal and paternal parenting styles were moderately correlated with alexithymia and depression. The paternal parenting style was also correlated with dissociation. Optimal parenting of one of the parents had a buffering effect on the degree of alexithymia, but not on the severity of other forms of affect dysregulation. The effect of sexual or physical abuse did not add to that of parental parenting style in terms of predicting affect dysregulation. However, a positively perceived maternal parenting style was found to have a buffering effect in terms of the degree of alexithymia, if sexual abuse had also taken place. CONCLUSIONS: Perceived parenting does appear to be of some significance in the development of alexithymia. Optimal parenting of one of the parents may protect against the development of alexithymia when the parenting of the other parent is perceived as non-optimal. However, it is likely that other factors besides parental care and sexual or physical abuse play an important role in the development of an adequate affect regulation.     

牛津单髁膝关节置换：长期结果

牛津膝置换是使用最广泛的膝关节单髁置换（UKR）。牛津膝在37年前开始应用,拥有一个全匹配的活动衬垫,因而磨损率非常低。牛津膝最主要的使用指征是膝关节前内侧骨关节炎,这种病人至少占所有需要行膝关节置换术患者的50％。由于这一系统的设计特点,传统UKR的反指征,如年龄、活动量、肥胖、髌股关节损害和软骨钙质沉着症等对于牛津膝均不是反指征。与全膝关节置换（TKR）相比,牛津膝提供更快的康复、更好的功能、更大的活动度和更好的术后满意度,发生并发症更少、程度更轻,病残率和死亡率更低。一个持续超过30年的研究显示在90％的病例中,牛津膝为患者终生提供了优或良的临床结果,且不需要翻修。在最近15年,牛津膝通过微创手术入路植入,涉及6000多例使用该入路牛津膝置换的9个研究报道显示,10年生存率约95％。在许多这样的研究中,医生们在拟行膝关节置换的患者中约50％使用了牛津单髁膝置换。     

缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性的变化

目的:制备大鼠在体缺血再灌注模型,观察缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性的变化。方法:实验于2005-03/2006-10在解放军沈阳军区总医院医学实验动物中心和全军心血管研究所实验室完成。实验分组:选用健康雌性SD大鼠36只,根据预适应程序分为第1,2,3次缺血,第1,2,3次再灌注,每一时间点6只大鼠。实验过程:用手术套管法造成左冠状动脉主干缺血及再灌注。所有实验动物在实验程序结束后,取出心脏迅速置液氮保存备用。实验评估:用放射免疫法测环磷酸腺苷水平,生化法测环磷酸腺苷依赖蛋白激酶活性变化。结果:36只大鼠均进入结果分析。①环磷酸腺苷含量:第1次再灌注组低于第1次缺血组[(0.325±0.015),(0.395±0.024)pmol/g,t=6.06,P<0.001],第2次再灌注组低于第2次缺血组[(0.523±0.017),(0.708±0.067)pmol/g,t=6.56,P<0.001],第3次再灌注组低于第3次缺血组[(0.567±0.031),(0.712±0.038)pmol/g,t=7.24,P<0.001]。②环磷酸腺苷依赖蛋白激酶活性:第1次再灌注组低于第1次缺血组[(10.115±1.000),(16.351±0.849)pkat/g,t=11.12,P<0.001],第2次再灌注组低于第2次缺血组[(11.877±2.213),(14.869±0.619)pkat/g,t=3.31,P<0.01],第3次再灌注组低于第3次缺血组[(11.745±0.987),(14.766±0.329)pkat/g,t=7.09,P<0.001]。③缺血预处理程序中心肌环磷酸腺苷含量及环磷酸腺苷依赖蛋白激酶活性随缺血及再灌注呈周期性波动。在5min缺血预处理时表现为明显增高,而在间隔的再灌注程序中恰呈相反改变,有明显下降的趋势。结论:环磷酸腺苷及环磷酸腺苷依赖蛋白激酶的周期性波动变化可能是激发心肌缺血预处理的机制之一,环磷酸腺苷可能在预处理保护作用中起一些作用。     

Presymptomatic DNA testing for Huntington disease: Identifying the need for psychological intervention

In the Dutch presymptomatic DNA-testing program for Huntington disease (HD), 29 individuals with increased risk and 44 with decreased risk were followed-up 6 months after test results. A prognostic model was built aimed at identifying individuals at risk for psychological maladjustment, as measured by the Impact of Event Scale, the Beck Hopelessness Scale, the General Health Questionnaire, and the Social Support Questionnaire. Results: 1) The more that applicants suffered from intrusive feelings about HD and tried to avoid HD-related situations, prior to the test, the greater the chance that they will experience this 6 months after the test if they proved to be at increased risk; 2) the more that both individuals with increased risk and those with decreased risk who suffered from the threat of having HD tried to avoid HD-related situations prior to the test and the less satisfied they were with available support, the greater the probability that they will show avoidance behavior after the test; 3) the more pessimistic that individuals with increased risk as well as those with decreased risk were about their future prior to the test, the more they avoided HD-related situations and the more dissatisfied they were about their available support (pretest), the greater the probability that they will become depressive and suicidal. Psychological adjustment was also studied as a function of a) intrusion/denialavoidance pattern over time and b) healthy mental functioning/future expectancies. Most individuals with increased risk (86%) seem to cope well thus far, although this was based largely on strong psychological defenses and dependent on satisfactory relationships. Five individuals with increased risk (17%) had either health complaints and/or extreme pessimistic expectancies. They were not able to face the consequences of the test result and showed an increase of denial-avoidance behavior thereafter. Seven out of 9 individuals with decreased risk, identified as possible psychopathological cases with pessimistic expectancies, had less intrusive feelings than prior to the test. This group could later develop severe problems with detachment from their previous life style and also with adapting to their new genetic status. We conclude that DNA-testing has shown benefits for most tested individuals. However, a considerable number are at risk for maladjustment and should be offered additional help. Further studies as to whether the strong defenses in individuals with increased risk safeguard adequate adjustment in the long term should be undertaken. © 1993 Wiley-Liss, Inc.     

Regional myocardial dysfunction: evaluation of patients with prior myocardial infarction with fast CT

A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.     

Report of the Dutch Health Council on the cost-effectiveness of long-term psychotherapy

A recent report from the Health Council of the Netherlands considers the cost-effectiveness of long-term psychotherapy (more than 25 sessions over a period of more than one year). It is concluded that knowledge about the efficacy and effectiveness of this form of therapy is scarce, and the cost-effectiveness is largely unknown. A plea is made for further research and for restraints in the administration of such therapy. However, research into the efficacy of long-term psychotherapy requires a controlled design, with the selection and randomisation of patients. This precludes definitive conclusions with regard to the cost-effectiveness in open patient groups. Moreover, psychotherapy is not only aimed at a cure, but also to a fairly large extent at care. Finally, if it is difficult to determine the efficacy of psychotherapy then this is even more so the case for long-term psychotherapy, as the success may be attributable to a wide range of intervening events that occur during the course of treatment.