Hemorrhagic colitis and hemolytic-uremic syndrome--E. coli as the etiologic agent. I. Bacteriology and pathogenesis

Since 1983 when the connection between haemorrhagic colitis (HC), haemolytic uraemic syndrome (HUS), and intestinal infections by verotoxin-producing E. coli (VTEC, EHEC) was demonstrated, a lot of arguments has been accumulated showing verotoxins (Shiga-like toxins, SLT) and adhesive fimbria to play a key role in the pathogenicity of the respective E. coli group. The toxins bind via Gb3 receptors to the target cells and after internalization inhibit the protein synthesis. Due to the particular clustering of receptors at cell surfaces, vascular endothelial cells, intestinal epithelial cells as well as kidney and nerve tissues are especially affected. The severity of illness is obviously dependent on the relation between release of toxins and the actual level of anti-toxin-IgG in the blood.     

Intrahepatic hematoma: a rare complication of exchange transfusion

A four-day-old male neonate who underwent three exchange transfusions for jaundice owing to ABO incompatibility on three consecutive days is presented. A large intrahepatic hematoma developed as a complication of the third exchange transfusion. The baby fully recovered.     

Respiratory sinus arrhythmia is reversed during positive pressure ventilation

In order to study the relationship between heart rate and depth of anaesthesia, respiratory sinus arrhythmia (RSA) was investigated during enflurane and isoflurane anaesthesia in 28 patients (15-39 years). Positive pressure ventilation (six breaths min-1) was used. Respiratory sinus arrhythmia was evaluated during light anaesthesia, deep anaesthesia (burst suppression in EEG) and light anaesthesia again by using signal averaging technique. In most patients, decrease of the heart rate was seen during inspiration (positive tracheal pressure), and increase during expiration. Respiratory sinus arrhythmia did not disappear in deep anaesthesia. Inter-individual variation in the magnitude and phase relationship of respiratory sinus arrhythmia was considerable, and was not associated to the level of anaesthesia.     

Incidence of fetal chromosome abnormalities in insulin dependent diabetic women.

In order to screen for fetal neural tube defects and chromosome abnormalities, amniocentesis was carried out in 334 women with insulin-dependent diabetes mellitus (IDDM) between 1979 and 1987. Two cases (0.6%; 95% confidence limits 0.1-2.2%) of fetal chromosome abnormality were found: one case of Klinefelter's syndrome and one case of de novo translocation. This is comparable to the overall incidence of chromosome abnormality found at birth and is also comparable to the incidence of fetal chromosome abnormality (1.0%) found by amniocentesis at our Department in a group of 2,264 young non-diabetic women with little risk of contracting genetic disorders. The results suggest that maternal IDDM does not increase the risk of fetal chromosome abnormality and consequently screening by amniocentesis for chromosome abnormalities among diabetic women does not seem to be indicated.     

Herpes simplex virus type 1 infection induces upregulation of interleukin-23 (p19) mRNA expression in trigeminal ganglia of BALB/c mice.

We investigated the expression kinetics of several cytokines in trigeminal ganglia (TG) and in brains of BALB/c mice during the course of ocular herpes simplex virus type 1 (HSV-1) infection. All mice recovered from the infection within 2 weeks. The quantitative rapid real-time RT-PCR method was used to analyze interleukin-4 (IL-4), interferon-gamma (IFN-gamma), IL-12p35, IL-12p40, and the recently described IL-23 (p19) mRNA in TG, brain, and splenocyte samples. In TG, we found elevated expression of mRNA for IL-23 (p19) from early acute infection (day 3) to the beginning of the latent phase (day 14). The increase was not detected in brain or in the spleen. IL-4 expression occurred in both TG and brain from the beginning of the experiment to the latent phase. During the latent phase (days 14 and 31), IL-4 expression was significantly elevated in the brain when compared with the uninfected controls (p < 0.05). Considerable expression of IFN-gamma mRNA was detected in TG of mice during acute HSV-1 infection. The expression of IL-23 was detected also in the brains of the mice, even though no significant changes were found during the acute HSV-1 infection. This is, to our knowledge, the first report to show elevated expression of IL-23 (p19) mRNA (p < 0.05) during viral infection in TG of mice.     

周围剂量当量仪的研制

周围剂量当量仪研制是根据国际辐射单位和测量委员会（ＩＣＲＵ）３９号报告推荐的周围剂量当量而设计的一种数字化智能型辐射防护仪。方法采用能量补偿对探测器进行能响校正。结果补偿结果使得探测器在４７～２３０ｋｅＶ与ＩＳＯ推荐的Ｈ＊（１０）／Ｋａ值误差在５％以内。本文重点描述了周围剂量当量仪探测器部分的工艺结构和剂量学性能以及电子学测量部分的主要功能。结论通过实际应用我们初步获得的结论是由于该仪器可直接测量周围剂量当量，稳定性好且具有自动取平均值特点，它可做为实验室校准用测量仪器，又由于该仪器体积小，电池供电，读数面板又有背光功能，它也可以做为现场仪器用于辐射防护实践的现场测量     

Substance P augments the rate of vasodilation induced by calcitonin gene-related peptide in porcine ophthalmic artery in vitro.

Peptides may function as neurotransmitters liberated antidromically by sensory nerve fibres, provoking vascular responses having potential importance in some neurological disorders. Dose-response relaxation curves induced by substance P (SP) and calcitonin gene related peptide (CGRP) have been studied in porcine ophthalmic arteries in vitro. Both peptides induced vasodilation when tested separately (CGRP much greater than SP). Because of the putative interactions between such peptides in this vascular territory, a computerised system was also used for analysing over time the response to a single addition of either 10(-8) M CGRP, 10(-8) M SP or a combination of 10(-8) M SP + 10(-8) M CGRP. SP did not augment the maximum relaxation induced by CGRP alone, but increased significantly the rate of relaxation during the initial phase of the response. The effect induced by the SP+CGRP combination was stronger than the sum of the individual SP and CGRP-induced relaxations during the first 4 min of the response, which suggests a SP-CGRP synergism in this artery.     

MR imaging, flow and motion.

The present work is intended as a nonmathematical review of the role of flow and motion in nuclear magnetic resonance (MR) imaging. A historical review of MR flow measurement techniques is given, followed by a short overview of flow models in vitro and in vivo. The theory behind the influence of motion on the modulus and phase MR signal information is discussed and effects such as washin/washout, flow-induced signal void, phase offset, and phase dispersion are defined. A simple approach to the concept of MR angiography is given, and methods for quantitative flow measurements such as the phase mapping technique, are surveyed. Aspects of the measurement of diffusion and microcirculation are given, and finally, an overview of the role of MR flow imaging in present and future clinical application is given.