Evaluation of the epidermal refractive index measured by optical coherence tomography

BACKGROUND/AIMS: It has recently been proposed that the refractive index (RI) measured by means of optical coherence tomography (OCT) may be a valid measure for hydration of skin. In this pilot study, using OCT in vivo, we aimed to investigate the interday variability of RI measurements and acute changes of RI following the application of a moisturizer. METHODS: Twenty healthy Caucasian volunteers were investigated on their forearms using a commercially available OCT system (SkinDex 300, ISIS optronics GmbH, Mannheim, Germany) fitted with an integrated algorithm for the evaluation of the RI. The interday repeatability of the OCT method was determined performing symmetrical measurements on both forearms on day 1, 5, 9, and 13. In order to investigate the acute effect of a moisturizer on RI, OCT assessments were performed before and 10 min after the application of an aqueous lotion with a lipophilic phase. As a control, the contralateral site was investigated in the same way, except for the use of distilled water instead of the lotion. RESULTS: Assessments of interday variability revealed insignificant (P>0.05) variances between the four measurement times as expressed in very small repeatability coefficients (right arm: 0.039; left arm 0.053) and small coefficients of variance (right arm: 1.02%; left arm: 1.38%). With regard to the RIs measured over time, we could not observe significant (P>0.05) differences between the two symmetrical anatomic sites (mean+/-SD of RI: 1.3893+/-0.0142 (right arm); 1.3875+/-0.0192 (left arm)). The acute effect of the moisturizer was indicated by a significant decrease of the RI 5 min after the application of the lotion (1.399+/-0.01 vs. 1.387+/-0.02; difference between means: 0.012; P=0.033; 95% confidence interval: 0.001-0.0023). However the control site treated with distilled water did not show significant differences between the two measurement times (1.387+/-0.013 vs. 1.391+/-0.023; difference between means: -0.004; P=0.57; 95% confidence interval: -0.019-0.011). CONCLUSIONS: In this pilot study, we have demonstrated that RI evaluation via OCT is a promising technique that may be used for the assessment of skin hydration in vivo. However, the direct comparison of OCT with standard methods, ideally such as nuclear magnetic resonance spectroscopy, is necessary.     

Pain induced by low-grade stress in patients with fibromyalgia and chronic shoulder/neck pain, relation to surface electromyography.

The mechanisms of pain causation in fibromyalgia (FMS) and chronic shoulder/neck pain (SNP) are still debated. We wanted to compare muscle activity and pain development during and after low-grade mental stress in FMS and SNP patients. Twenty-three women with FMS, 29 women with chronic SNP and 35 healthy women performed a stressful task lasting 60 min followed by a 30 min recovery period. We recorded surface electromyography over the trapezius, neck, temporalis and frontalis muscles. Subjects reported their pain at the corresponding locations together with the development of fatigue and perceived tension. Significant differences between FMS and SNP groups were not observed either for muscular or subjective responses. SNP patients and controls responded with more pain in the trapezius and neck regions than in the forehead, in contrast to FMS patients who had a more generalized pain response. Development of pain, tension and fatigue was not related to muscle activity for any group. We conclude that FMS and SNP patients have similar pain and electromyographic responses. The results suggest that similar pathophysiological mechanisms are involved although the responses are more generalised in FMS than in SNP patients. Muscular activity did not explain the pain which developed during the stressful task for either group. Pain lasted longer during recovery in both FMS and SNP patients compared to healthy controls, possibly a result of disease-related sensitisation in pain pathways.     

Norepinephrine transporter (NET) promoter and 5'-UTR polymorphisms: association analysis in panic disorder

Several biochemical and pharmacological studies suggest that the catecholaminergic system involving the norepinephrine transporter (NET) is relevant for the pathogenesis of panic disorder. Three single nucleotide polymorphisms in the promoter or untranslated 5' region of the NET gene were investigated by means of RFLP analysis in a sample of 115 German patients with panic disorder and 115 matched controls. Statistical analysis failed to show association with the overall diagnosis of panic disorder. In the subgroup of patients with panic disorder without agoraphobia, however, two polymorphisms were found to be associated with the disease (G/C (rs2397771): p < 0.05; T/C (rs2242446): p < 0.01). While our data do not support a major function of the NET gene in the development of panic disorder, it may play a role in the subgroup of panic disorder without agoraphobia.     

The differentiation between pancreatic neoplastic cysts and pancreatic pseudocyst.

The number of small and often asymptomatic cystic lesions detected in pancreas has increased during the last decade. Historically the vast majority of the pancreatic cystic lesions were considered pseudocysts, but in recent series the incidence of various neoplastic cysts, such as intraductal papillary mucinous neoplasm, serous cystadenomas and cystic endocrine tumours, has increased. The possible malignant potential in these cystic neoplasms warrants careful diagnostic workup to choose the optimal treatment for each patient. Patient's age, symptoms and a possible history of acute or chronic pancreatitis with known aetiology together with high quality imaging studies are important in the differential diagnosis between pseudocysts and neoplastic cysts. Endoscopic ultrasound, cyst fluid analysis and positron emission tomography may be used in selected patients, but the accuracy of these methods needs further investigation.     

Risk-taking behavior and accidents in adolescence in developed countries

Injuries due to accidents are the primary cause of fatalities among adolescents. Between the ages of 10 and 19, mortality caused by accidents augments significantly, and there is an excess of male mortality, increasing with age. This mortality has remained virtually unchanged over the past 25 years, except for a small narrowing of rate differences by sex. Traffic accidents, particularly those involving motorcycles, are the leading cause of accident fatalities. Though not easily assessed, morbidity due to accidents is probably very high, especially among males. Sports accidents are the most frequent. Adolescents appear to be particularly exposed to some risks, but also tend to be careless about safety. Risk-taking is a source of rewards: pleasure, self-affirmation, sense of independence; but it is described by some authors as self-destructiveness, death from accidents reflecting suicidal tendencies. Paradoxical results of prevention have been observed in this age group.     

Acute coronary syndromes

The first 150 words of the full text of this article appear below. Key points Coronary artery disease accounts for >30% ofdeaths in Western society. The diagnosis of myocardial infarctionshould be qualified by size, causation and time from occurrence. Mortalityis reduced by immediate or ‘primary’ percutaneouscoronary intervention or thrombolysis within the first 24 hof onset of ST-segment elevation myocardial infarction. Strategiesto reduce platelet activation (glycoprotein IIb/IIIa receptorantagonists, or clopidogrel) are now recommended in the treatmentof high-risk non-ST-segment myocardial infarction/unstable angina. Elevatedserum troponins may be the result of non-ischaemic myocardialdamage, especially in critical illness.