Increases in lipids and immune cells in response to exercise and mental stress in patients with suspected coronary artery disease: effects of adjustment for shifts in plasma volume

This study examined the role of shifts in plasma volume on lipid and immune reactions to stress. Lipid, immune, rheological, and cardiovascular reactions to exercise and mental stress in 51 patients with suspected coronary artery disease were determined. Blood pressure and heart rate were measured during and blood samples taken at the end of each rest and task. Lipids (total cholesterol, triglycerides, HDL, LDL) and immune cells (lymphocytes, monocytes, granulocytes) increased with exercise, whereas cholesterol, LDL, and lymphocytes increased with mental stress. Plasma volume decreased by 1 and 5% following mental and exercise stress, respectively. The task-induced increases in lipids were no longer statistically significant following adjustment for changes in plasma volume, whereas the increases in immune cell numbers survived such correction. This study provides evidence that, in coronary artery disease patients, exercise and mental stress-induced increases in lipids but not immune cells can be largely accounted for by shifts in plasma volume.     

Mechanisms of virus-induced asthma exacerbations: state-of-the-art. A GA2LEN and InterAirways document

Viral infections of the respiratory tract are the most common precipitants of acute asthma exacerbations. Exacerbations are only poorly responsive to current asthma therapies and new approaches to therapy are needed. Viruses, most frequently human rhinoviruses (RV), infect the airway epithelium, generate local and systemic immune responses, as well as neural responses, inducing inflammation and airway hyperresponsiveness. Using in vitro and in vivo experimental models the role of various proinflammatory or anti-inflammatory mediators, antiviral responses and molecular pathways that lead from infection to symptoms has been partly unravelled. In particular, mechanisms of susceptibility to viral infection have been identified and the bronchial epithelium appeared to be a key player. Nevertheless, additional understanding of the integration between the diverse elements of the antiviral response, especially in the context of allergic airway inflammation, as well as the interactions between viral infections and other stimuli that affect airway inflammation and responsiveness may lead to novel strategies in treating and/or preventing asthma exacerbations. This review presents the current knowledge and highlights areas in need of further research.     

Histopathological characteristics of small diameter melanocytic naevi

BACKGROUND/AIMS: The clinical definition of an atypical naevus ("dysplastic naevus" or "naevus with architectural disorder and cytological atypia of melanocytes") stresses size larger than 5 mm in diameter as a major diagnostic criterion. Because malignant melanomas and their precursors may arise in smaller lesions, a histological study of melanocytic lesions smaller than 4 mm in diameter was conducted to evaluate their histological appearance. METHODS: Two hundred and sixty one naevi smaller than 4 mm in diameter were collected and characterised by histological examination into benign naevi without architectural disorder and naevi with architectural disorder and mild, moderate, and severe atypical melanocytes according to criteria used on larger lesions. RESULTS: Small melanocytic naevi covered the same complex histological spectrum from benign naevi to severely atypical naevi when compared with larger lesions. A high proportion of small naevi (72%) exhibited features diagnostic for naevi with architectural disorder and cytological atypia. CONCLUSION: There is a discrepancy between histological and clinically defined atypical naevi. The same generally accepted criteria for the histological diagnosis of atypical naevi should be used for small melanocytic naevi in addition to large ones. Thus, small naevi exhibiting atypical features on histological examination should be categorised as atypical naevi, regardless of their small diameter.     

Reliability of hematocrit during rest and stress in healthy adults

Hematocrit has been implicated in the triggering of cardiovascular events and the development of cardiovascular disease. Studies have demonstrated the reliability of hematocrit at rest, however, data are lacking about hematocrit during repeated acute stress exposures. The current study assessed the reliability of hematocrit during rest and stress. Hematocrit was measured in two sessions during rest and in response to mental, cold and exercise stress in 84 healthy men and women. The stress tasks consistently elicited increases in hematocrit. Absolute levels of hematocrit were highly reliable between testing sessions. Changes in hematocrit with exercise stress were reliable whereas changes associated with mental and cold stress were not reliable between sessions. The findings indicate that hemoconcentration during brief mental and physical stress is more reliable for absolute levels than change scores. The reliability of stress-induced hemoconcentration may be improved by more provocative challenges and repeated sampling during stress.     

Phylogenetic analysis of human G9P[8] rotavirus strains circulating in Jiangsu,China between 2010 and 2016

Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis.     

Short echo time MR spectroscopy of brain tumors: Grading of cerebral gliomas by correlation analysis of normalized spectral amplitudes

Purpose:

To process single voxel spectra of low‐ and high‐grade gliomas. To propose correlation analysis of the scatter plots of normalized spectral amplitudes as a pattern recognition tool for the classification (grading) of brain tumors. To propose a spectrum processing approach that improves the differentiation of proton spectra with dominating macromolecule and lipid peaks.

Materials and Methods:

LCModel was used to process spectra. Mean metabolite concentrations and mean normalized spectra were obtained for normal white matter and for gliomas. The mean spectra of macromolecules and lipids (ML) in the range 1.4–0.9 ppm, and mean difference spectra (DS) without ML and lactate were computed. Correlation analysis of the scatter plot of the patient and mean normalized spectral amplitudes and dispersion of the scatter plot points were used for classification and grading of tumors.

Results:

It was found advantageous to perform the classifications using DS spectra. The shape of ML spectrum and concentration of tCr seem to be a good markers for glioma grade.

Conclusion:

Combining a qualitative comparison of the patient and mean DS spectra of the tumors using correlation analysis of normalized spectra amplitudes with a quantitative comparison of metabolite concentrations is a powerful tool in studying brain lesions. J. Magn. Reson. Imaging 2010;31:39–45. © 2009 Wiley‐Liss, Inc.