Properties of hemoglobin and dextran-hemoglobin rightshifted by oxidized inositol tetrakisphosphate

Phytate was digested by wheat bran phytase to yield inositol tetrakisphosphate. Periodate-oxidized inositol tetrakisphosphate (oxyIP4) was coupled by means of reductive alkylation to hemoglobin and the covalent dextran-hemoglobin conjugate to yield the rightshifted (rs) compounds rsHb and rsDxHb, respectively. The variations of the oxygen dissociation curves of these molecules with pH and temperature were compared to those of hemoglobin. The variations with pH were found to be less pronounced for these rightshifted forms. An extensive decrease in the half-saturation oxygen tension was observed, however, with both rsHb and rsDxHb, as in the case of unmodified Hb. Modification of hemoglobin by oxyIP4 at the polyphosphate site was suggested by the lack of a further rightshifting effect of phytate on rsHb, and by the similarity between the difference spectrum of rs-methemoglobin and the difference spectrum induced by the addition of phytate.     

Photodynamic therapy in the bladder: Can the light dose be easily quantified?

The shape of the bladder and the optical characteristics of the tissue within the wall can be shown to play an important role in the amount of light actually received at the wall. The use of estimated doses even assuming spherical geometry, cannot therefore be relied upon. This paper describes some experimental work carried out on a glass model that was used to simulate the bladder. A specially constructed dual detector was used which consisted of an isotropic probe and semiconductor detector. This enabled measurements of irradiance and space irradiance (light energy fluence rate) to be made simultaneously. By changing the optical characteristics of the wall a four-fold increase in space irradiance was measured. Contamination of the water contained within the model by blood was also investigated and has shown that with concentrations as low as 0.5% the delivered light dose reaching the wall can be reduced by up to 50% at a wavelength of 510 nm. Some in vivo measurements are also presented together with some comments on the difficulties that have been encountered when transferring measurements from the model to the patient.     

Mathematical aspects of the paternity index I=X/Y,especially in relation to the chance of non-exclusion of non-fathers

Summary In a previous paper the author mentioned some aspects of the paternity index I (=X/Y): Among false triplets the frequency of those with I equal to or higher than an (observed) I value of I ^x is considerably lower than 1/I ^x; among false triplets the mean value of I is equal to 1, and among non-excluded non-fathers it is equal to the inverse of the chance of non-exclusion; among true triplets the mean value of 1/I (=i) is equal to the chance of non-exclusion of non-fathers. In a statistical material rather strong deviations from some of these expectations were observed.In the present paper further characteristics of the distribution of I values were taken into consideration, and especially those that should hold if lnI would fit in with a normal distribution. It was supposed that with the aid of such a distribution the deviations mentioned above could be recognized as chance variability. It appears, however, that neither the logarithms of the paternity index, nor those of the zygosity index of twins (chosen as an analogous model that is more easily analysable than the paternity index) are really normally distributed. This, in turn, makes that estimates of probability of paternity, based on such a supposition, are of doubtful reliability. Besides it is concluded that also for other reasons other estimates than Essen-Möller's W (or I or i), as probability of first type errors, lead in practice to conclusions that are equally subdue to a priori suppositions as are W values and may be, in fact, much more erroneous than those.Special attention is paid to the statistical analysis of paternity studies with more than one alleged father, and it is concluded that in such cases the general formula that may be considered to be equivalent with Essen-Möller's formula for one-man paternity cases, i.e., W=X/(X+Y) or I/(I+1), must be W ₁=I ₁/(I+n); W ₂=I ₂/(I+n) etc. and certainly not W ₁=I ₁/(I+1); W ₂=I ₂/(I+1) etc.Dedicated to Prof. Dr. Erik Essen-Möller on the occasion of his 80th birthday     

Development of a miniature undulation pump for the distributed artificial heart

Research of the distributed artificial heart is important not only to acquire the means of individual organ perfusion but also to clarify the characteristics of the organ and the mechanism of blood distribution. To investigate the distributed artificial heart, the miniature undulation pump was developed. The outer diameter and the thickness of the developed pump were 38 mm and 11 mm, respectively. The priming volume of the pump was 3.2 ml. The total size including the motor unit was 38 mm in diameter and 32 mm in length. The total weight was 67.5 g. The total volume was 27.5 ml. The pump was driven with pulse width modulation by using a 1 chip motor controller. More than 5 L/min of continuous output could be obtained. The results showed that the developed miniature undulation pump system had enough performance for individual organ perfusion.     

拉萨市藏汉族婴儿动脉血氧饱和度调查分析

目的证实在高原低氧环境下，世居藏族婴儿比汉族婴儿具有较强的维持体内氧供能力。方法采用动脉血氧饱和度仪在海拔３６５８ｍ、大气压６５．３ｋＰａ（１ｋＰａ＝７．５ｍｍＨｇ）的拉萨市，对１４例藏族婴儿和１５例汉族婴儿，从出生到生后４个月在清醒、浅睡、深睡及吃奶４种状态下的动脉血氧饱和度（ＳａＯ２）进行了动态监测。结果（１）两组婴儿出生后最初４８小时内的ＳａＯ２均显示高水平状态，睡眠时ＳａＯ２低于清醒时ＳａＯ２；（２）汉族婴儿生后第１天～４个月的４种生理状态下ＳａＯ２均低于藏族婴儿；（３）汉族婴儿的低氧血症临床体征，如睡眠和吃奶时紫绀等比藏族婴儿频发。结论遗传性适应可能是藏族婴儿具有足够血氧程度的基础     

Prevention of precipitated withdrawal symptoms by activating central cholinergic systems during a dependence-producing schedule of morphine in rats

Previous studies in this and other laboratories have suggested an important role for central cholinergic neurons in the expression of morphine withdrawal symptoms. This study was designed to determine whether the symptoms of withdrawal could be mitigated by normalization of the effect of morphine on cholinergic neurons. Since this effect is generally inhibitory, we used centrally acting cholinergic agonists to augment central cholinergic tone during chronic morphine infusion. Rats were made dependent following the intra-arterial (i.a.) infusion of increasing concentrations (35-100 mg kg(-1) day(-1)) of morphine over 5 days. I.a. injection of 0.5 mg/kg of naloxone precipitated a profound withdrawal response that included a dramatic increase in mean arterial pressure (MAP) which was maintained over the 60-min observation period, a short duration increase in heart rate (HR), and characteristic opiate withdrawal symptoms. In separate groups of rats, non-toxic doses (50 and 250 microg/kg) of the acetylcholinesterase (AChE) inhibitor, diisopropylflurophosphate (DFP) were administered as single daily injections concomitant with the morphine infusion. DFP treated rats, exhibited significantly reduced expression of the naloxone-evoked pressor response. The apparent anti-withdrawal effect of DFP was not reproduced by the selective peripherally acting AChE inhibitor, echothiophate, although both compounds effectively reduced the expression of certain other withdrawal symptoms. The centrally acting muscarinic cholinergic receptor agonist, arecoline, resulted in an even more impressive suppression of withdrawal symptoms. While not all symptoms associated with morphine withdrawal are mediated via central cholinergic pathways, these results suggest that physical dependence on morphine can be suppressed to a significant degree by the augmentation of central cholinergic activity during morphine administration.     

Conditioned fear to environmental context: cardiovascular and behavioral components in the rat

This study compares the time course of the cardiovascular changes (mean arterial blood pressure, heart rate) and behavioral changes (freezing, rearing, grooming and activity) evoked by 30 min long exposures to a footshock chamber before and after conditioning with footshocks. The main finding is that the conditioned fear evoked by re-exposure to the footshock chamber after conditioning is associated with a prolonged freezing response, a marked rise in mean arterial pressure (+35 mm Hg above a resting baseline of 105 mm Hg) and a delayed rise in heart rate. The pattern of behavioral and cardiovascular changes is the same as with conditioned fear to a discrete stimulus but the effect is a lot longer.     

P16在宫颈癌组织中的表达及意义

目的研究P16在宫颈癌组织中的表达情况.方法用免疫组化S-P法检测15例正常宫颈组织,20例慢性宫颈炎和42例宫颈癌组织中P16的表达.结果P16宫颈癌中的阳性率为45.2%,其表达与宫颈癌的临床分期显著相关(P＜0.05).结论P16的异常表达与宫颈癌的发生和发展有关,可作为判断预后的辅助指标.     

脑梗死患者血脂水平检测及临床意义

目的探讨血脂水平与脑梗死的关系。方法通过对137例急性脑梗死患者与对照组血脂变化观察,多因素分析用SPSS10.0软件包中的Logistic回归方程,计算相对危险度(RR),RR的95%可信限(CI)。结果脑梗死组TC、TG、LDL-C浓度均明显高于对照组,而HDL-C浓度明显低于对照组。结论血清TC>6.0mmol/L才增加脑梗死的风险,而HDL-C浓度≥0.85mmol/L可降低脑梗死的风险。     

健康教育干预在慢性病防治中的作用

目的探讨健康教育干预在慢性病防治中的作用。方法根据干部体检结果,对该人群采取了健康教育干预,尤其对其中确诊的812例高血压、753例心电图异常、691例高脂血症、289例糖尿病、218例糖耐量异常及143例高尿酸血症患者(以上称慢病跟踪组)进行了规范化管理和治疗,2年后复检,并对有关项目的检查进行对比。结果干预后该人群高血压、心电图异常、高脂血症、糖尿病及糖耐量异常的发生明显下降,χ2值分别为7.32、4.36、7.53、7.63、8.35(P<0.01、0.05);慢病跟踪组通过行为加药物的干预性治疗,高血压、高脂血症、糖尿病等平均控制达标率为80%以上。结论健康教育干预是预防慢性病的重要策略和有效手段。