Speech‐in‐noise understanding in older age: The role of inhibitory cortical responses

Studies of central auditory processing underlying speech‐in‐noise (SIN) recognition in aging have mainly concerned the degrading neural representation of speech sound in the auditory brainstem and cortex. Less attention has been paid to the aging‐related decline of inhibitory function, which reduces the ability to suppress distraction from irrelevant sensory input. In a response suppression paradigm, young and older adults listened to sequences of three short sounds during MEG recording. The amplitudes of the cortical P30 response and the 40‐Hz transient gamma response were compared with age, hearing loss and SIN performance. Sensory gating, indicated by the P30 amplitude ratio between the last and the first responses, was reduced in older compared to young listeners. Sensory gating was correlated with age in the older adults but not with hearing loss nor with SIN understanding. The transient gamma response expressed less response suppression. However, the gamma amplitude increased with age and SIN loss. Comparisons of linear multi‐variable modeling showed a stronger brain–behavior relationship between the gamma amplitude and SIN performance than between gamma and age or hearing loss. The findings support the hypothesis that aging‐related changes in the balance between inhibitory and excitatory neural mechanisms modify the generation of gamma oscillations, which impacts on perceptual binding and consequently on SIN understanding abilities. In conclusion, SIN recognition in older age is less affected by central auditory processing at the level of sensation, indicated by sensory gating, but is strongly affected at the level of perceptual organization, indicated by the correlation with the gamma responses.     

Contribution of Cyanotoxins to the Ecotoxicological Role of Lichens

The fascinating world of lichens draws the attention of the researchers because of the numerous properties of lichens used traditionally and, in modern times, as a raw material for medicines and in the perfumery industry, for food and spices, for fodder, as dyes, and for other various purposes all over the world. However, lichens being widespread symbiotic entities between fungi and photosynthetic partners may acquire toxic features due to either the fungi, algae, or cyano-procaryotes producing toxins. By this way, several common lichens acquire toxic features. In this survey, recent data about the ecology, phytogenetics, and biology of some lichens with respect to the associated toxin-producing cyanoprokaryotes in different habitats around the world are discussed. Special attention is paid to the common toxins, called microcystin and nodularin, produced mainly by the Nostoc species. The effective application of a series of modern research methods to approach the issue of lichen toxicity as contributed by the cyanophotobiont partner is emphasized.     

Coronary thrombi neovascularization in patients with ST-elevation myocardial infarction - clinical and angiographic implications

Introduction

Coronary artery thrombosis in ST-elevation myocardial infarction (STEMI) is a dynamic process often preceded by episodes of silent plaque rupture and subocclusive thrombosis. Thrombus organization is achieved by ingrowth of endothelial and smooth muscle cells. Clinical significance and impact of thrombus neovascularization on primary percutaneous coronary intervention (pPCI) outcome remain unclear. Therefore we investigated composition and neovascularization of thrombi aspirated during pPCI and their association with clinical and angiographic parameters of STEMI patients.

Methods

Aspirated thrombi retrieved from 84 STEMI patients were classified as fresh (< 1 day), lytic (1-5 days) or organized (> 5 days). Thrombus neovascularization was evaluated immunohistochemically using CD34, CD31 and VEGF antibodies. CD34 and CD31 immunopositive (CD34/CD31 +) cells were organized as single, clusters and microvessels. VEGF positivity was graded as low or high, based on thrombus surface immunopositive area.

Results

CD34/CD31 + cells were present in 67% of all aspirated thrombi. Thrombus CD34/CD31 positivity was associated with previous history of angina pectoris (χ² = 6.142, p = 0.013) and lower myocardial blush grade (MBG < 3, χ² = 12.602, p < 0.001). Organization of CD34/CD31 + cells showed inverse association with the extent of VEGF positivity (χ² = 10.607, p = 0.005). Fresh thrombi were associated with shorter ischemic time (U = 237.5, p = 0.002) and MBG 3 (χ² = 6.379, p = 0.012).

Conclusions

Older thrombus age and neovascularization are associated with suboptimal myocardial perfusion in STEMI patients. Thrombus VEGF expression is inversely associated with degree of CD34 + cell organization. Therefore, neovascularization of aspirated thrombi may indicate the duration of thrombosis, coronary microcirculation status and outcome in STEMI patients.     

Naphthalene in the treatment of patients with atopic dermatitis

Atopic dermatitis is a chronic relapsing inflammatory skin disease the incidence of which has been constantly growing in all age groups. Research into the use of naphthalene in the treatment of patients with psoriasis proved its anti-inflammatory and antiproliferative effects as well as a satisfactory remission for months in more than 70% of treated patients with psoriasis. The present study was undertaken to investigate the efficacy of naphthalene in the treatment of patients with atopic dermatitis. According to study results, naphthalene therapy proved efficacious and free from side effects in 20 atopic dermatitis patients.     

Xanthoma disseminatum: case report

Xanthoma disseminatum is a rare, benign, non-Langerhans' cell histiocytic disorder of unknown etiology. A case is presented of a 71-year-old man with a three-year history of disseminated symmetric yellowish papules and plaques on the skin of the face, neck, flexor regions, trunk, extremities and oral mucosa, with fatty infiltration of the liver and pancreas, and cardiac complaints. Xanthomatous rhinophyma predominated on the face. Clinical, immunohistochemistry and histology findings indicated the diagnosis of xanthoma disseminatum. Although the patient had a positive family history of cardiovascular diseases and a number of symptoms that are often associated with hyperlipidemia, repeat plasma levels were always within the normal limits. The case was interesting because of a number of etiologic factors that could be connected with the appearance of xanthomas in our patient. Therefore it was difficult to classify the disease into one of well-defined nosologic entities. The case report is supplemented with a review of relevant literature.