The melatonergic pathway and its interactions in modulating respiratory system disorders.

Melatonin is a key intracellular neuroimmune-endocrine regulator and coordinator of multiple complex and interrelated biological processes. The main functions of melatonin include the regulation of neuroendocrine and antioxidant system activity, blood pressure, rhythms of the sleep-wake cycle, the retardation of ageing processes, as well as reseting and optimizing mitochondria and thereby the cells of the immune system. Melatonin and its agonists have therefore been mooted as a treatment option across a wide array of medical disorders. This article reviews the role of melatonin in the regulation of respiratory system functions under normal and pathological conditions. Melatonin can normalize the structural and functional organization of damaged lung tissues, by a number of mechanisms, including the regulation of signaling molecules, oxidant status, lipid raft function, optimized mitochondrial function and reseting of the immune response over the circadian rhythm. Consequently, melatonin has potential clinical utility for bronchial asthma, chronic obstructive pulmonary disease, lung cancer, lung vascular diseases, as well as pulmonary and viral infections. The integration of melatonin's effects with the alpha 7 nicotinic receptor and the aryl hydrocarbon receptor in the regulation of mitochondrial function are proposed as a wider framework for understanding the role of melatonin across a wide array of diverse pulmonary disorders.

Application of the allogenic mesenchymal stem cells in the therapy of the bladder tuberculosis.

Urogenital tuberculosis (TB) often leads to contraction of the bladder, a reduction of the urinary reservoir capacity, and, in the latest stage, to real microcystitis up to full obliteration. Bladder TB Stage 4 is unsuitable for conservative therapy, and cystectomy with subsequent enteroplasty is indicated. In this study, using a model of bladder TB in New Zealand rabbits, the therapeutic efficacy of the interstitial injection of autologous bone-derived mesenchymal stem cells (MSCs) combined with standard anti-TB treatment in the restoration of the bladder function was demonstrated. For analysis of the MSC distribution in tissues, the latter were labelled with superparamagnetic iron oxide nanoparticles. In vitro studies demonstrated the high intracellular incorporation of nanoparticles and the absence of cytotoxicity on MSC viability and proliferation. A single-dose administration of MSCs into the bladder mucosal layer significantly reduced the wall deformation and inflammation and hindered the development of fibrosis, which was proven by the subsequent histological assay. Confocal microscopy studies of the bladder cryosections confirmed the presence of superparamagnetic iron oxide nanoparticle-labelled MSCs in different bladder layers of the treated animals, thus indicating the role of stem cells in bladder regeneration.

Bilateral cavitary multidrug- or extensively drug-resistant tuberculosis: role of surgery.

OBJECTIVES: Cavitary disease and bilateral lesions are among the risk factors for poor outcome of pulmonary tuberculosis (TB). Our aim was to explore the value and limits of surgery in patients with advanced TB. METHODS: A retrospective study of 57 consecutive patients who underwent thoracic surgery for culture-positive bilateral cavitary pulmonary TB was performed. Forty-four (77.2%) patients were men and 13 (22.8%) patients were women; their ages were in the range of 18-61 years. Twenty-two (38.6%) patients had multidrug-resistant (MDR) TB and 35 (61.4%) patients had extensively drug-resistant (XDR) TB confirmed with cultures. On admission, 49 (86.0%) patients had sputum smear microscopy positive for acid-fast bacilli. The main indication for surgery was treatment failure manifested as contagious persisting cavities despite best available therapy. The surgical procedures included combinations of pulmonary resections of different levels, selective thoracoplasties and/or endobronchial valve treatment. The operations were performed consecutively, starting with the most affected side. TB therapy preceded the operation for a minimum of 6 months and was continued after the operation on the basis of the patient's susceptibility to drugs for Mycobacterium tuberculosis. RESULTS: We performed 121 operations: 42 in 22 patients with MDR TB (1.9 operations per patient) and 79 procedures in 35 patients with XDR TB (2.3 operations per patient). No deaths occurred in the 1st year. Two late deaths followed, 1 unrelated to and 1 due to TB progression. Ten major complications (1 complication per patient) developed: main bronchus stump fistula (n = 4), prolonged air leak (n = 3), respiratory failure (n = 2) and wound seroma (n = 1). At the 1-month follow-up visit, sputum smear conversion was observed in 11 (68.8%) patients with MDR and in 15 (45.5%) patients with XDR TB. At the late (20-36 months) follow-up visit, culture negativity was achieved in 21 (95.5%) patients with MDR TB and in 23 (65.7%) patients with XDR TB (P = 0.015). CONCLUSIONS: Thoracic surgery may significantly improve patients' outcomes and even result in a cure in a good portion of patients with bilateral cavitary MDR and XDR TB and should be considered as the essential element of multimodality treatment for MDR and XDR TB, even in patients with bilateral cavitary disease and borderline respiratory reserves.