Matrix metalloproteinases 2 and 9 increase permeability of sheep pleura in vitro

Background: Matrix metalloproteinases (MMPs) 2 and 9 are two gelatinase members which have been found elevated in exudative pleural effusions. In endothelial cells these MMPs increase paracellular permeability via the disruption of tight junction (TJ) proteins occludin and claudin. In the present study it was investigated if MMP2 and MMP9 alter permeability properties of the pleura tissue by degradation of TJ proteins in pleural mesothelium. Results: In the present study the transmesothelial resistance (RTM) of sheep pleura tissue was recorded in Ussing chambers after the addition of MMP2 or MMP9. Both enzymes reduced RTM of the pleura, implying an increase in pleural permeability. The localization and expression of TJ proteins, occludin and claudin-1, were assessed after incubation with MMPs by indirect immunofluorescence and western blot analysis. Our results revealed that incubation with MMPs did not alter neither proteins localization at cell periphery nor their expression. Conclusions: MMP2 and MMP9 increase the permeability of sheep pleura and this finding suggests a role for MMPs in pleural fluid formation. Tight junction proteins remain intact after incubation with MMPs, contrary to previous studies which have shown TJ degradation by MMPs. Probably MMP2 and MMP9 augment pleural permeability via other mechanisms. Backgroun

Pleural Transport Physiology: Insights from Biological Marker Measurements in Transudates

Aims: The aim of this study was to evaluate the physicochemical properties of the pleural mesothelial barrier and of the biological markers that facilitate or eliminate the passage of molecules through the pleura. Methods and Material: Pleural fluid samples from sixty-five patients with heart failure were analyzed. The biological markers studied were lactate dehydrogenase (LDH), adenosine deaminase (ADA), interleukin-6 (IL-6), C reactive protein (CRP), tumor necrosis factor-α (TNF-α), carcinoembryonic antigen (CEA), copper/zinc superoxide dismutase (CuZnSOD), matrix metalloproteinase-2 (MMP-2), -3 (MMP-3), -7(MMP-7), -8 (MMP-8) and -9 (MMP-9). Based on the pleural fluid/serum ratio, these molecules were divided into three groups: a) the LDH-like group with a pleural fluid/serum ratio between 0,4 and 0,8 (LDH, CEA, CuZnSOD, ADA, CRP, MMP-8), b) molecules with a pleural fluid/serum ratio less than 0,4 (MMP-7 and MMP-9) and c) molecules with a pleural fluid/serum ratio equal or above 1 (TNF-α, IL-6, MMP-2 and MMP-3). Results: No correlation between the molecular radius and the pleural fluid to serum ratio of the above biological markers was found. Conclusions: The molecular size is not a major determinant for the passage of molecules through the mesothelial barrier. Several other factors may influence the transport of the above molecules to pleural cavity, such as their charge and shape. © Eleni et al

Surveillance study of vector species on board passenger ships, Risk factors related to infestations

<p>Abstract</p> <p>Background</p> <p>Passenger ships provide conditions suitable for the survival and growth of pest populations. Arthropods and rodents can gain access directly from the ships' open spaces, can be carried in shiploads, or can be found on humans or animals as ectoparasites. Vectors on board ships may contaminate stored foods, transmit illness on board, or, introduce diseases in new areas. Pest species, ship areas facilitating infestations, and different risk factors related to infestations were identified in 21 ferries.</p> <p>Methods</p> <p>486 traps for insects and rodents were placed in 21 ferries. Archives of Public Health Authorities were reviewed to identify complaints regarding the presence of pest species on board ferries from 1994 to 2004. A detail questionnaire was used to collect data on ship characteristics and pest control practices.</p> <p>Results</p> <p>Eighteen ferries were infested with flies (85.7%), 11 with cockroaches (52.3%), three with bedbugs, and one with fleas. Other species had been found on board were ants, spiders, butterflies, beetles, and a lizard. A total of 431 <it>Blattella germanica </it>species were captured in 28 (9.96%) traps, and 84.2% of them were nymphs. One ship was highly infested. Cockroach infestation was negatively associated with ferries in which Hazard Analysis Critical Control Point system was applied to ensure food safety on board (Relative Risk, RR = 0.23, <it>p </it>= 0.03), and positively associated with ferries in which cockroaches were observed by crew (RR = 4.09, <it>p </it>= 0.007), no cockroach monitoring log was kept (RR = 5.00, <it>p </it>= 0.02), and pesticide sprays for domestic use were applied by crew (RR = 4.00, <it>p </it>= 0.05). Cockroach infested ships had higher age (<it>p </it>= 0.03). Neither rats nor mice were found on any ship, but three ferries had been infested with a rodent in the past.</p> <p>Conclusion</p> <p>Integrated pest control programs should include continuing monitoring for a variety of pest species in different ship locations; pest control measures should be more persistent in older ships. HACCP system aids in the prevention of cockroach infestations on board.</p

Self-reported risk of obstructive sleep apnea syndrome, and awareness about it in the community of 4 insular complexes comprising 41 Greek Islands

Obstructive Sleep Apnea Syndrome (OSAS) is a chronic disease that significantly increases morbidity and mortality of the affected population. There is lack of data concerning the OSAS prevalence in the insular part of Greece. The purpose of this study was to investigate the self-reported prevalence of OSAS in 4 Greek insular complexes comprising 41 islands, and to assess the awareness of the population regarding OSAS and its diagnosis. Our study comprised 700 participants from 41 islands of the Ionian, Cyclades, Dodecanese and Northeast Aegean island complexes that were studied by means of questionnaires via a telephone randomized survey (responsiveness rate of 25.74%). Participants were assessed by the Berlin Questionnaire (BQ) for evaluation of OSA risk, by the Epworth Sleepiness Scale (ESS) for evaluation of excessive daytime sleepiness, and by 3 questions regarding the knowledge and diagnosis of OSAS. The percentage of participants at high risk according to BQ was 27.29% and the percentage of people who were at high risk according to ESS was 15.43%. A percentage of 6.29% of the population was at high risk for OSAS (high risk both in BQ and ESS). A high percentage of 73.43%, were aware of OSAS as a syndrome however a significantly less percentage (28.00%) was aware of how a diagnosis of OSAS is established. The community prevalence of OSAS in Greek islands in combination with the low-level awareness of the OSAS diagnostic methods highlights the need for development of health promotion programs aiming at increasing the detection of patients at risk while increasing the awareness of OSAS

Φυσιολογία υπεζωκοτικής κοιλότητας: επιδράσεις αμιλορίδης, ουαμπαΐνης, νιτροπρωσσικού νατρίου, 17β οιστραδιόλης και προγεστερόνης στη διακίνηση του υπεζωκοτικού υγρού

The pleural space is a real space between the lungs and the chest wall. It contains a small amount of fluid and facilitates smooth movement of the lungs within the thoracic cavity. Although this is a major function of the pleural space, obliteration of the space either surgically or chemically doesnot interfere significantly with an individual’s ability to breathe. On the other hand, disease of the pleural membranes or excess fluid in the pleural space can have a significant effect on breathing.It has been suggested that the pleural space also offers a safe route of egress for pulmonary edema fluid. Although a large amount of fluid in the pleural space can cause symptoms, it has a less negative impact on breathing than does the same volume of fluid within lung parenchyma. The parietal pleura plays a major role in the removal of pleural fluid. By general consent, pleural liquid was entered from the parietal (highpressure) pleura and was absorbed in the visceral (low-ressure) pleura. The occurrence of an active electrolyte transport and diffusion by mesothelial cells has become content of research with contradictory results. However, there are still unanswered questions and considerable controversies about the physiologic importance of pleural liquid and about the nature of the forces governing its movement into, within, and out of the pleural cavity.The fluid and solute transport properties of pleura tissue were studied using specimens of intact visceral and parietal pleura from adult sheeps. The samples were transferred to the laboratory within 1 hour from the death of the animal in a Krebs-Ringer solution at 4oC. The pleura was then mounted as a planar sheet in Ussing-type chamber. The spontaneous potential difference and the inhibitory effects of nitroprusside sodium, ouabain, amiloride, 17β estradiol and progesterone on transepithelial electrical resistance (RTE) were measured. The spontaneous potential difference across parietal pleura was 0.5 ± 0.1 mV whereas that across visceral pleura was 0.4 ±0.1 mV. Electrical Λ resistance of both pleura was very low 22.02 ±4.1 Ω cm for visceral pleura and 22.02 ± 3.5 Ω cm2 for parietal pleura. There was increase in the Rte when sodium nitroprusside was added to the serosal bathing solution of parietal pleura and to the serosal or mucosal bathing solution in visceral pleura. The same was observed when ouabain was added in mucosal surface of visceral pleura and either to the mucosal or serosal surface of parietal pleura. Furthermore, there was increase in RTE when amiloride was added to the serosal bathing solution of parietal pleura. There was an increase in RTE in all of the samples examined after addition of 17β estradiol and progesterone in visceral and parietal pleura. This increase was rapid within 1 min, lasted for about 15 min, returned to the basal level within 30-45 min, and was dose dependent. Tamoxifen, anestrogen receptor antagonist, did not completely inhibit the effect of 17β estradiol; furthermore no steroid receptors were identified in cytosolic preparations of visceral and parietal pleura, with ligand binding assays. The estrogen and progesterone induced increase in RTE was affected by additionof an inhibitor of the nitric oxide synthase in both visceral and parietal pleura. Indeed, previous administration of N“-nitro-L-argrinine methyl ester (L-NAME) prevented the increase in RTE by of 17β estradiol and progesterone. Consequently, the sheep pleura appear to play a role in the fluid and solute transport between the pleural capillaries and the pleural space. Their results suggest that there was a Na+ and K+ transport across either visceral or parietal pleura. Furthermore 17β estradiol and progesterone induce an increase in RTE in both visceral and parietal pleura and thus alter the transepithelial permeability. The effect of steroids may be accounted by rapid release of nitric oxide in pleura.Η υπεζωκοτική κοιλότητα είναι ένας πραγματικός χώρος μεταξύ των πνευμόνων και του θωρακικού τοιχώματος. Περιέχει μια μικρή ποσότητα υπεζωκοτικού υγρού και διευκολύνει τις κινήσεις των πνευμόνων μέσα στη θωρακική κοιλότητα. Παρόλο που αυτή είναι η κύρια λειτουργία της υπεζωκοτικής κοιλότητας, εξάλειψη της κοιλότητας είτε χειρουργικά είτε χημικά δεν εμποδίζει σημαντικά την ικανότητα των ατόμων να αναπνέουν. Από την άλλη πλευρά νοσήματα των πετάλων του υπεζωκότα ή συλλογή υγρού στην υπεζωκοτική κοιλότητα μπορεί να επηρεάσει σημαντικά τηναναπνοή. Έχει προταθεί ότι η υπεζωκοτική κοιλότητα προσφέρει επίσης μια ασφαλή οδό απομάκρυνσης του υγρού του πνευμονικού οιδήματος. Αν και μεγάλη ποσότητα υγρού στην υπεζωκοτική κοιλότητα προκαλεί συμπτώματα, έχει λιγότερο αρνητική επίδραση στην αναπνοή από ότι ο ίδιος όγκος υγρού στο πνευμονικό παρέγχυμα. Ο τοιχωματικός υπεζωκότας έχει σημαντικό ρόλο στην απομάκρυνση του υπεζωκοτικού υγρού. Σύμφωνα με την επικρατούσα θεωρία η διακίνηση του υπεζωκοτικού υγρού στηρίζεται στις διαφορές των πιέσεων μεταξύ των δύο πετάλων του υπεζωκότα. Η ύπαρξη ενεργητικής μεταφοράς και διάχυσης ουσιών έχει γίνει αντικείμενο έρευνας με αντικρουόμενα αποτελέσματα. Υπάρχουν ακόμη αναπάντητα ερωτήματα και σημαντικές διαφωνίες για τη φυσιολογική σημασία του υπεζωκοτικού υγρού και για τη φύση των δυνάμεων που κατευθύνουν τη διακίνηση του προς τα μέσα και έξω από την υπεζωκοτική κοιλότητα. Η διακίνηση ηλεκτρολυτών και η επίδραση στεροειδών ορμονών εξετάστηκε σε υπεζωκότα προβάτου. Γ ια το σκοπό αυτό χρησιμοποιήθηκαν ακέραια τμήματα τοιχωματικού και πνευμονικού υπεζωκότα από 80 ενήλικα πρόβατα (θηλυκά και αρσενικά). Τα δείγματα μεταφέρθηκαν στο εργαστήριο σε οξυγονωμένο διάλυμα Krebs στους 4ο C εντός μισής ώρας από το θάνατο του ζώου. Στη συνέχεια ο υπεζωκότας τοποθετήθηκε σε μια αντλία τύπου Ussing, με διάλυμα Krebs και από τις δύο πλευρές,οξυγονώνονταν συνεχώς και διατηρούνταν σε θερμοκρασία 37ο C. Μελετήθηκαν η ανάπτυξη διαφοράς δυναμικού και οι επιδράσεις του νιτροπρωσσικού νατρίου, της ουαμπαίνης, της αμιλορίδης, της 17β οιστραδιόλης και της προγεστερόνης στην ηλεκτρική αντίσταση (RTE)της μεμβράνης. Η διαφορά δυναμικού που αναπτύχθηκε στον τοιχωματικό υπεζωκότα ήταν 0,5 ±0,1 mV ενώ στον πνευμονικό ήταν 0,4 ±0,1 mV. Η αντίσταση και για τα δύο πέταλα του υπεζωκότα ήταν χαμηλή, 22,02 ±4,1 Ω cm2 για τον πνευμονικό υπεζωκότα και 22,03 ± 3,5 Ω cm2 για τον τοιχωματικό υπεζωκότα. Αύξηση της Rte παρατηρήθηκε όταν νιτροπρωσσικό νάτριο προστέθηκε στην πλευρά προς την υπεζωκοτική κοιλότητα του τοιχωματικού υπεζωκότα και στην έσω ή έξω πλευρά του πνευμονικού υπεζωκότα. Το ίδιο παρατηρήθηκε και όταν ουαμπαίνη προστέθηκε στηνπλευρά προς τον ενδιάμεσο ιστό του πνευμονικού υπεζωκότα και στον τοιχωματικό υπεζωκότα και από τις δύο πλευρές. Επιπλέον υπήρξε αύξηση της RTE όταν αμιλορίδη προστέθηκε στην πλευρά προς την υπεζωκοτική κοιλότητα του τοιχωματικού υπεζωκότα. Αύξηση της RTE υπήρξε σε όλα τα δείγματα που εξετάστηκαν μετά τη προσθήκη 17β οιστραδιόλης και προγεστερόνης σε τοιχωματικό και πνευμονικό υπεζωκότα. Η αύξηση ήταν άμεση, στο πρώτο λεπτό της έκθεσης, διαρκούσε περίπου 15 λεπτά, επέστρεφε στα αρχικά επίπεδα σε 30-45 λεπτά και ήταν δοσοεξαρτώμενη. Η ταμοξιφαίνη, ένας ανταγωνιστής των υποδοχέων της οιστραδιόλης, δεν ανέστειλε πλήρως την επίδραση της οιστραδιόλης. Επιπλέον υποδοχείς οιστρογόνων και προγεστερόνης δεν αναγνωρίστηκαν στα πέταλα του υπεζωκότα. Η εξαρτώμενη από τα οιστρογόνα και την προγεστερόνη αύξηση της RTE επηρεάστηκε από την προσθήκη ενός αναστολέα της συνθάσης του οξειδίου του αζώτου. Πράγματι η προσθήκη του αναστολέα απέτρεψε τη αύξηση της RTE.Συμπερασματικά φαίνεται πως υπάρχει μετακίνηση ιόντων και στα δύο πέταλα του υπεζωκότα. Τα μεσοθηλιακά κύτταρα συμμετέχουν ενεργά στην ανταλλαγή νερού και ηλεκτρολυτών μεταξύ των τριχοειδών του υπεζωκότα και της υπεζωκοτικής κοιλότητας. Επιπρόσθετα τα οιστρογόνα και η προγεστερόνη τροποποιούν τη διαπερατότητα του υπεζωκότα. Στην τροποποίηση της διαπερατότητας μπορεί να συμμετέχει η γρήγορη απελευθέρωση οξειδίου του αζώτου στον υπεζωκότα

Carbon Nanotubes and Other Engineered Nanoparticles Induced Pathophysiology on Mesothelial Cells and Mesothelial Membranes

Nanoparticles have great potential for numerous applications due to their unique physicochemical properties. However, concerns have been raised that they may induce deleterious effects on biological systems. There is accumulating evidence that, like asbestos, inhaled nanomaterials of &gt;5 μm and high aspect ratio (3:1), particularly rod-like carbon nanotubes, may inflict pleural disease including mesothelioma. Additionally, a recent set of case reports suggests that inhalation of polyacrylate/nanosilica could in part be associated with inflammation and fibrosis of the pleura of factory workers. However, the adverse outcomes of nanoparticle exposure to mesothelial tissues are still largely unexplored. In that context, the present review aims to provide an overview of the relevant pathophysiological implications involving toxicological studies describing effects of engineered nanoparticles on mesothelial cells and membranes. In vitro studies primarily emphasize on simulating cellular uptake and toxicity of nanotubes on benign or malignant cell lines. On the other hand, in vivo studies focus on illustrating endpoints of serosal pathology in rodent animal models. From a molecular aspect, some nanoparticle categories are shown to be cytotoxic and genotoxic after acute treatment, whereas chronic incubation may lead to malignant-like transformation. At an organism level, a number of fibrous shaped nanotubes are related with features of chronic inflammation and MWCNT-7 is the only type to consistently inflict mesothelioma

Identification of Genes and miRNAs Associated with TAFI-Related Thrombosis: An in Silico Study

Thrombin-Activatable Fibrinolysis Inhibitor (TAFI) is a carboxypeptidase B-like proenzyme encoded by the CPB2 gene. After thrombin activation, TAFI downregulates fibrinolysis, thus linking the latter with coagulation. TAFI has been shown to play a role in venous and arterial thrombotic diseases, yet, data regarding the molecular mechanisms underlying its function have been conflicting. In this study, we focused on the prediction and functional enrichment analysis (FEA) of the TAFI interaction network and the microRNAs (miRNAs) targeting the members of this network in an attempt to identify novel components and pathways of TAFI-related thrombosis. To this end, we used nine bioinformatics software tools. We found that the TAFI interactome consists of 28 unique genes mainly involved in hemostasis. Twenty-four miRNAs were predicted to target these genes. Co-annotation analysis of the predicted interactors with respect to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and transcription factors (TFs) pointed to the complement and coagulation cascades as well as neutrophil extracellular trap formation. Cancer, stroke, and intracranial aneurysm were among the top 20 significant diseases related to the identified miRNAs. We reason that the predicted biomolecules should be further studied in the context of TAFI-related thrombosis