Looking at the heart of low and high heart rate variability fearful flyers: self-reported anxiety when confronting feared stimuli

Previous research has shown that phobic subjects with low heart rate variability (HRV) are less able to inhibit an inappropriate response when confronted with threatening words compared to phobic subjects with high HRV [Johnsen, B.H., Thayer, J.F., Laberg, J.C., Wormnes, B., Raadal, M., Skaret, E., et al., 2003. Attentional and physiological characteristics of patients with dental anxiety. Journal of Anxiety Disorders, 17, 75–87]. The aim of this study was to evaluate changes in self-reported anxiety when low HRV and high HRV fearful flyers (N = 15) and a matched control group (N = 15) were exposed to flight-related pictures, flight-related sounds or both pictures and sounds. We hypothesized that sounds would be crucial to evoke fear. Also, low HRV fearful flyers were expected to report higher anxiety than high HRV fearful flyers assuming anxiety as their inappropriate response. Decreases on HRV measures were also predicted for a subgroup of phobic participants (N = 10) when confronted with the feared stimuli. Our data supported the hypothesis that sounds are crucial in this kind of phobia. Low HRV fearful flyers reported higher anxiety than high HRV fearful flyers in two out of three aversive conditions. The predicted HRV decreases were not found in this study. Results are discussed in the context of avoidance of exposure-based treatments.     

Analytical assessment of MALDI-TOF Imaging Mass Spectrometry on thin histological samples. An insight in proteome investigation

BACKGROUND: The development of MALDI Imaging Mass Spectrometry is a promising technique in the investigation of biological molecular repertoire. We have pursued an analytical assessment of this technique in its application to proteome analysis. METHODS: A specific statistical method of analysis has been developed to enable data processing in the absence of internal standards, by defining similarity scores. RESULTS: The investigated linear mode MALDI-TOF set-up allows to obtain data variations comprised within the 30% of variation when assaying tissues samples from the same animal, while the 60% of variation was highlighted in the inter-mice series assaying syngenic animals. CONCLUSIONS: This analytical assessment represents the first step of a process that should validate the utilisation of this technique in the clinical practice.     

Cx26 gene mutations in idiopathic progressive hearing loss

OBJECTIVE: The present study evaluated the frequency and type of mutations throughout the entire GJB2 region in a population of 39 patients affected with sporadic progressive "idiopathic" hearing loss. MATERIAL: A large series of patients suffering from progressive hearing loss underwent a systematic screening program to identify the etiology of the hearing loss. Of these patients, 39 presented with sporadic idiopathic progressive hearing loss and were included in this study. METHOD: We performed molecular analysis of GJB2 in each patient sequencing the genomic deoxyribonucleic acid (DNA) in both directions for detection of GJB2 mutations. Furthermore, in all patients bearing a Cx26 mutation, a search was also conducted for mutations or deletions of GJB6 (Cx30 gene) and for the A1555G mutation of the mitochondrial DNA. A control group was also considered to evaluate the frequency of Cx26 mutations in the normal population. RESULTS: A Cx26 gene mutation was detected in nine cases. One subject was found to bear a homozygous genotype for the 35delG mutation, another subject was compound heterozygous for 35delG and E47X, and the remaining patients showed heterozygous genotypes (35delG, L90P, R127H, M34T, V153I, V37I). No mutation or delection of the Cx30 gene was observed in these nine patients, and none of them presented with the A1555G mutation in the mitochondrial DNA. In the control group (40 individuals), a Cx26 mutation was detected in two cases (5%). CONCLUSIONS: About 23% of our patients (nine subjects) presented with mutations in GJB2, and 18% (seven subjects) were heterozygous. However, most of the described mutations are recessive, so a monogenic model of inheritance cannot explain the deafness phenotype. On the basis of these findings, we can speculate that the heterozygote Cx26 genotype could be a cause of progressive hearing loss, probably in association with mutations in other alleles. Thus, we recommend carefully following all hearing-impaired subjects with GJB2 mutations, even if they present with only mild hearing loss, because the hearing deficit could worsen. Furthermore, molecular analysis of the Cx26 gene should also be performed in adult patients affected with idiopathic progressive hearing loss.     

Loss of PNA staining in mouse aortico-pulmonary septum is associated with mesenchymal cell apoptosis

Massive apoptosis of mesenchymal cells in the septum of the aortico-pulmonary trunk was found in mouse fetuses at stage 14.5 dpc. It was associated with the appearance of cavities in the mesenchymal tissue, presumably due to cell loss, a strong reduction in the extent of lectin PNA staining, and the induction of metallothioneins in specialized mesenchymal cells. Cell loss was spatially restricted to an inner area of the septum and was due to a distinct apoptotic pattern of cells, different from that in the heart wall. These events led to a rapid reduction of the aortico-pulmonary septum as occurs during the late stages of heart morphogenesis. It coincided with the migration of other cell types that invaded the cell-depleted septum, and contributed to the histiogenesis of the mature heart.     

alpha-Dystroglycan does not play a major pathogenic role in autosomal recessive hereditary inclusion-body myopathy

Mutations of the GNE gene are responsible for autosomal recessive hereditary inclusion-body myopathy (HIBM). In this study we searched for the presence of any significant abnormality of alpha-dystroglycan (alpha-DG), a highly glycosylated component of the dystrophin-glycoprotein complex, in 5 HIBM patients which were previously clinically and genetically characterized. Immunocytochemical and immunoblot analysis showed that alpha-DG extracted from muscle biopsies was normally expressed and displayed its typical molecular mass. Immunoblot analysis on the wheat germ lectin-enriched glycoprotein fraction of muscles and primary myotubes showed a reduced amount of alpha-DG in 4 out of 5 HIBM patients, compared to normal and other diseased muscles. However, such altered lectin-binding behaviour, possibly reflecting a partial hyposialylation of alpha-DG, did not affect the laminin binding properties of alpha-DG. Therefore, the subtle changes within the alpha-DG glycosylation pattern, detected in HIBM muscles, likely do not play a key pathogenic role in this disorder.     

Masked hypertension in adults

A body of evidence indicates that masked hypertension is a significant predictor of cardiovascular disease, but how to identify these patients is still a matter of dispute. Data obtained in several cross-sectional studies have demonstrated that masked hypertension is associated with increased left ventricular mass index and carotid intima-media thickness, and impaired large artery distensibility. Furthermore, in longitudinal studies, masked hypertension was a strong predictor of cardiovascular morbidity and mortality. Several factors that can selectively raise ambulatory blood pressure increase the likelihood of having masked hypertension. These include younger age, smoking, alcohol use, contraceptive use in women, sedentary habits and central obesity. In addition, masked hypertension is more common in individuals with high-normal clinic blood pressure or transiently elevated blood pressure. Increased reactivity to daily life stressors and behavioural factors are other important predictors of masked hypertension. In clinical practice, masked hypertension should be searched for in individuals who are more likely to have this condition or are at increased risk of cardiovascular events including those with coronary, cerebrovascular or kidney disease, patients with diabetes and individuals with a high cardiovascular risk profile. To determine whether the use of ambulatory blood pressure monitoring is cost-effective in these individuals, further research is needed.