Early detection of the covert onset and evolution of critical illness polyneuromyopathy

Introduction: Critical illness polyneuropathy was first identifiedby Bolton and colleagues¹ and weakness due to neuropathic and/ormyopathic abnormalities is now recognized as a common complicationof prolonged critical illness.² The presence of abnormally lowcompound motor action potentials (CMAPs) is considered an importantdiagnostic criterion. The onset and evolution of this conditionfollowing intensive care unit admission has not previously beensystematically investigated. Methods: A prospective, sequential study of all patients thoughtlikely to require intensive care for 7 days or more was performedover a 12-month period. Admission APACHE II score, daily organfailure score, presence of sepsis, ventilation mode and routinehaematology and biochemistry results were recorded. A dailyneurological examination and weekly neurophysiological studieswere performed for the duration of the patients’ ICU stay.The neurophysiological studies included CMAPs, nerve conductionvelocities, sensory action potential amplitudes and electromyography.The Spearman correlation coefficient was used to analyse associationsbetween the recorded physiological data and serial CMAPs. Inour institution the lower limits of normal for ulnar and commonperoneal nerve CMAPs are 2.5 and 2.8 mV respectively. Results: Thirty-two patients were recruited to the study, ofwhom 23 survived for 7 days or longer. One patient was withdrawnat a relative’s request and two patients continued toreceive muscle relaxants until death. The median age was 61yr (range 33–80) and median admission APACHE II scorewas 20 (9–33). A significant positive correlation wasfound between serum albumin and CMAPs (P<0.05). CMAPs ofone patient are shown in Fig 3. Thirteen patients had threeor more sets of neurophysiological studies. CMAPs were foundto be low or fell during episodes of sepsis, at a time whenit was not possible to detect weakness clinically, and CMAPsrecovered as sepsis subsided. Of the eight patients who survived,six had severe clinical weakness of MRC grade 3 or less. Conclusions: The onset of critical illness motor syndrome mayprecede by days or weeks clinically detectable weakness, seemsto be associated with episodes of sepsis and can occur withindays of the onset of sepsis. Recovery in CMAPs may be equallyrapid as sepsis subsides.     

Heating of food and haemoglobin adducts from carcinogens: possible precursor role of glycidol.

Studies of adducts from reactive compounds to haemoglobin (Hb) by gas chromatography-tandem mass spectrometry according to the N-alkyl Edman method reveals the occurrence of N-(2,3-dihydroxypropyl)valine (diHOPrVal) at levels of 1-2 pmol/g Hb, in persons without known exposure. The hypothesis that this background originates from glycidol or related compounds during heating of food was tested in experiments with rats. Animals fed fried animal feed for 30 or 72 days showed an increase of the diHOPrVal level by about 50% compared with controls. Several arguments, such as the formation of reactive oxiranes by heat-induced dehydration of glycol configurations in glycerol and sugars, support the idea that glycidol (or e.g. glycidyl esters) are precursors of the adduct. In Hb samples, reduced for stabilisation of aldehyde adducts, relatively high levels of adducts determined as diHOPrVal were found, although without significant relation to frying of the feed. There is thus no indication that reduction in vivo of, for example, the Schiff base from glyceraldehyde, is a pathway for formation of the diHOPrVal. The background level of diHOPrVal in humans Hb is low, and the cancer risk associated with exposure to the specific alkylator-probably glycidol-formed in cooking, is therefore presumably low. The result implies, however, that low-molecular mass mutagenic oxiranes formed during the heating of food should be studied further.     

Epicardial adipose tissue volume estimation by postmortem computed tomography of eviscerated hearts

Epicardial adipose tissue (EAT) may play a role in the development of coronary artery disease. The purpose of this study was to evaluate a method based on postmortem computed tomography (PMCT) for the estimation of EAT volume. We PMCT-scanned the eviscerated hearts of 144 deceased individuals, who underwent a medicolegal autopsy. Using Mimics® we performed segmentation of the images and obtained the volumes of EAT and myocardium. Total heart volume was calculated by adding the volumes of EAT and myocardium. Total heart weight, including EAT, myocardium and attached vessels, was measured during autopsy. Inter-observer analysis was performed on 30 randomly chosen subjects. We included 132 individuals in the results (age range: 22–94 years; 56% men). Twelve individuals were excluded due to inadequate PMCT scanning. Median EAT volume was 73.0 mL (Interquartile range; IQR: 45.6–113.7 mL) in men and 64.8 mL (IQR: 44.0–98.0 mL) in women, which accounted for 20.4 ± 10.2% and 21.9 ± 9.5% of total heart volume, respectively. This corresponded with former autopsy studies. Total heart volume measured by PMCT was highly correlated with heart weight (R² = 90%). Mean inter-observer difference of EAT volume was ?1.7 mL (95% limits of agreement: ?37.0-33.6 mL), with an Intra Class Correlation of 0.91. It was possible to estimate EAT volume using PMCT on eviscerated human hearts. Our method was fast and accurate with good inter-observer agreement. This is a useful method to determine EAT at autopsy, and we will apply this method in future research.     

The psychology of potential threat: Properties of the security motivation system

Results of three experiments support hypothesized properties of the security motivation system, a special motivational system for handling potential threats, as proposed by Szechtman and Woody (2004). First, mild stimuli suggesting potential harm produced a marked state of activation (evident in both objective and subjective measures), consistent with the hypothesis that the security motivation system is finely tuned for the detection of potential threat. Second, in the absence of corrective behavior, this evoked activation is persistent, supporting the hypothesis that once stimulated, the security motivation system produces an enduring motivational state involving the urge to engage in threat-reducing behavior. Third, engagement in corrective behavior was effective in returning activation levels to baseline, whereas cognitive reappraisal was not. These findings are consistent with the hypothesis that deactivation of the security motivation system depends on performance of security-related behaviors, rather than non-behavioral events such as cognitive re-evaluation of threat.     

Malignancy and cancer treatment-related hair and nail changes

The hair and nails are complex cutaneous adnexal structures influenced by the patient's physiologic state. Systemic diseases may affect either or both. Remote internal malignancies may induce skin changes that are neither genetically related nor part of a tumor syndrome. The treatment of cancer with chemotherapy and radiation therapy may also induce abnormalities of the hair and nails. In this article, various paraneoplastic and cancer treatment-related hair and nail changes are described. The proper evaluation of such abnormalities may allow for the prompt and efficient diagnosis and management of an internal malignancy. Establishing an understanding of hair and nail abnormalities can be vital in assessing a patient's overall health, especially in the context of cancer detection and treatment.