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Open access

Ljerka Prester

windows and central heating system. Allergy 2000;55:79-83. de Andrade D, Birnbaum J, Lanteaume A, Izard JL, Corget P, Artillan MF, Toumi M, Vervloet D, Charpin D. Housing and house-dust mites. Allergy 1995;50:142-6. Hallas TE, Gislason D, Björnsdottir US, Jörundsdottir KB, Janson C, Luczynska CM, Gislason T. Sensitization to house dust mites in Reykjavik, Iceland, in the absence of domestic exposure to mites. Allergy 2004;59:515-9. Mihrshahi S, Marks G, Vanlaar C, Tovey E, Peat J. Predictors

Open access

Nigus Dessalew

Investigation of the structural requirement for inhibiting HIV integrase: QSAR study

HIV integrase has emerged as a promising target for discovery of agents against the acquired immunodeficiency syndrome (AIDS) pandemic. With the purpose of designing new chemotypes with enhanced potencies against the HIV integrase enzyme, the QSAR study carried out on 37 novel phthalimide derivatives is presented. The developed QSAR model was validated by standard statistical parameters and through a detailed structural study of how it reproduces and explains the quantitative differences seen in experimentally known pharmacological data. The model showed a good correlative and predictive ability having a cross-validated correlation coefficient (r 2 cv) of 0.709 and a conventional correlation coefficient (r 2) of 0.949. The predictive correlation coefficient (r 2 pred) was found to be 0.512. The study revealed that the antiretroviral activity is predominantly explained by the substituent size, shape and polarity and provided insights into how modulation of the steric bulkiness and polarities of the substituents could be made to optimize the integrase-inhibitor interaction chemistry. A detailed investigation was made of the structural basis for the antiretroviral activity and the findings from the study could be usefully employed to design antagonists with a much more enhanced potency and selectivity.

Open access

Mihaela Stanivuk

Rezime

Današnje kompanije su zavisne od nematerijalne imovine koju čine informacije, znanje, inovacije i kreativost, a to su glavni resursi digitalne ekonomije. Da bi se pojavile i opstale na globalnom tržištu, u digitalnom dobu, današnje kompanije moraju posjedovati performanse kojima će zasjeniti konkurenciju i ostvariti privredni progres. Te performanse se ogledaju u intelektualnom kapitalu, odnosno u umovima ljudskih resursa kompanije, njihovim međusobnim odnosima, kao i odnosima sa eksternim saradnicima. Intelektualni kapital je jedan od krucijalnih koncepata kreiranja konkurentske prednosti u digitalnoj ekonomiji. Cilj ovog rada je ukazivanje na skrivenu vrijednost intelektualnog kapitala koja već decenijama sazrijeva u tišini i čeka pravi trenutak da “eksplodira”. Znanje koje kompanija posjeduje, kao i način na koji ga primjenjuje danas je odlučujući faktor za ostvarivanje optimalnog razvoja potencijala digitalne ekonomije, te stvaranje stabilnog društvenog sistema. Predstavljajući različite metode mjerenja naučnici su omogućili ostvarivanje prava vlasništva i mjerenje intelektualnog kapitala kompanije. Od esencijalnog značaja je zaštita intelektualnog kapitala, jer u digitalnoj ekonomiji, gdje se gotovo sve vrši elektronski, pojam “zloupotreba” je dobio sasvim novo značenje. Naposljetku, intelektualni kapital je ultimatum neophodan za postizanje dominacije na globalnom tržištu i ostvarivanje ekonomskog prosperiteta.

Open access

Evrim Arzu Koçkaya, Güdeniz Selmanoğlu, Nesrin Özsoy and Nursel Gül

Evaluation of Patulin Toxicity in the Thymus of Growing Male Rats

Patulin is a mycotoxin produced by several Penicillium, Aspergillus, and Byssachlamys species growing on food products. In this study, we investigated the effects of patulin on the thymus of growing male rats aged five to six weeks. The rats were receiving it orally at a dose of 0.1 mg kg-1 bw a day for either 60 or 90 days. At the end of the experiment, the thymus was examined for histopathology by light microscopy and for epidermal growth factor (EGF) and its receptor (EGFR) by immunolocalisation. For morphometry we used the Bs200prop program to analyse images obtained with the Olympus BX51 light microscope. Cell ultrastructure was studied by electron microscopy. In rats treated with patulin, the thymus showed haemorrhage, plasma cell hyperplasia, a dilation and fibrosis in the cortex, enlarged interstitial tissue between the thymic lobules, enlarged fat tissue, thinning of the cortex, and blurring of the cortico-medullary demarcation. Electron microscopy showed signs of cell destruction, abnormalities of the nucleus and organelles, and loss of mitochondrial cristae. However, no differences were observed in thymus EGF and EGFR immunoreactivity between treated and control rats.

Open access

Horst Thiermann, Kai Kehe, Dirk Steinritz, John Mikler, Ira Hill, Thomas Zilker, Peter Eyer and Franz Worek

Red Blood Cell Acetylcholinesterase and Plasma Butyrylcholinesterase Status: Important Indicators for the Treatment of Patients Poisoned by Organophosphorus Compounds

Inhibition of acetylcholinesterase (AChE) is regarded as the primary toxic mechanism of organophosphorus compounds (OP). Therapeutic strategies are directed to antagonise overstimulation of muscarinic receptors with atropine and to reactivate inhibited AChE with oximes. Reactivation is crucial within the neuromuscular synapse, where atropine is ineffective, since peripheral neuromuscular block eventually leads to respiratory failure. Patients with OP intoxication have to be identified as early as possible.

During an international NBC-defence exercise anesthetised pigs were poisoned with sarin, followed by treatment with atropine and oxime. Blood samples were drawn and red blood cell (RBC)-AChE activity determined with a fielded test system on-site. Within a few minutes the poisoning was verified. After administration of HI-6, RBC-AChE activity increased rapidly. Blood samples were reanalysed in our laboratory in Munich. Almost identical course of the AChE activities was recorded by both systems.

The more comprehensive cholinesterase status was determined in Munich. Oxime administration can be stopped when AChE is aged completely, but has to be continued as long as poison is present in the body and reactivation is possible.

To aid the on-site physician in optimising diagnosis and treatment, a fielded test system should be available to allow rapid determination of the complete cholinesterase status.

Open access

Rajashekar Barkur, Muddanna Rao and Laxminarayana Bairy

. Neurochem Res 1997;22:1119-25. Chen H, Ma T, Ho IK. Effects of developmental lead exposure on inhibitory avoidance learning and glutamate receptors in rats. Environ Toxicol Pharmacol 2001;9:185-91. Gilbert ME, Kelly ME, Samsam TE, Goodman JH. Chronic developmental lead exposure reduces neurogenesis in adult rat hippocampus but does not impair spatial learning. Toxicol Sci 2005; 86:365-74. Lilienthal H, Winneke G, Ewert T. Effects of lead on neurophysiological and performance measures: animal and

Open access

Maja Peraica, Ana-Marija Domijan and Marko Šarić

Mycotoxic and Aristolochic Acid Theories of the Development of Endemic Nephropathy

Despite many efforts of scientists and epidemiologists, the aetiology of endemic nephropathy (EN) is still unknown. This disease occurs in the rural population of geographically limited areas of Bulgaria, Bosnia and Herzegovina, Croatia, Romania, and Serbia, and a number of theories have been proposed about its aetiology. The mycotoxin theory has prevailed until now, based on the studies of nephrotoxic mycotoxin ochratoxin A (OTA) that revealed higher frequency of OTA-positive food and blood samples in endemic than in non-endemic areas.

However, a new aristolochic acid (AA) theory of EN origin has been proposed recently, due to the histological similarities in kidney lesions between patients suffering from EN and patients suffering from Chinese herbs nephropathy caused by AA. Until now it has not been unequivocally proved that the inhabitants of EN areas are exposed to higher concentration of AA than in other regions and the exposure pathways are rather uncertain.

This paper presents most important studies supporting both theories, indicating also the inconsistencies of each.

Open access

Nataša Holcer Janev, Pavle Jeličić, Maja Grba Bujević and Damir Važanić

Abstract

Floods can pose a number of safety and health hazards for flood-affected populations and rescuers and bring risk of injuries, infections, and diseases due to exposure to pathogenic microorganisms and different biological and chemical contaminants. The risk factors and possible health consequences for the rescuers involved in evacuation and rescuing operations during the May 2014 flood crisis in Croatia are shown, as well as measures for the prevention of injuries and illnesses. In cases of extreme floods, divers play a particularly important role in rescuing and first-response activities. Rescuing in contaminated floodwaters means that the used equipment such as diving suits should be disinfected afterwards. The need for securing the implementation of minimal health and safety measures for involved rescuers is paramount. Data regarding injuries and disease occurrences among rescuers are relatively scarce, indicating the need for medical surveillance systems that would monitor and record all injuries and disease occurrences among rescuers in order to ensure sound epidemiological data. The harmful effects of flooding can be reduced by legislation, improvement of flood forecasting, establishing early warning systems, and appropriate planning and education.

Open access

Tomislav Ivanković, Jasna Hrenović, Grigorios Itskos, Nikolaos Koukouzas, Davor Kovačević and Jelena Milenković

Abstract

Wood fly ash is an industrial by-product of the combustion of different wood materials and is mostly disposed of as waste on landfills. In our preliminary experiments, wood ash exhibited antibacterial activity against urban wastewater bacteria and we focused on wood fly ash as a potential substrate for wastewater disinfection. The addition of ash at a concentration of 10 g L-1 (1 %) caused an instant increase of pH in urban wastewater and landfill leachate. High pH (10.1-12.7) inactivated bacterial populations in the wastewater and the removal of faecal coliforms and intestinal enterococci after 6 h of contact was 100 % (below the detection limit; <1 CFU per mL) with the most efficient ash sample (ash from combustion of beech) both in urban wastewater and landfill leachate. Properly chosen wood fly ash, i.e. one that tends to increase the pH to the greatest extent, proved to be a very effective disinfection substrate. Considering that water treated with wood ash has a high pH and needs to be neutralised before discharge, ash would be suitable for disinfection of leachates when smaller volumes are treated

Open access

Bensu Karahalil, Esra Emerce, Bülent Koçer, Serdar Han, Necati Alkiş and Ali Karakaya

The Association of OGG1 Ser326Cys Polymorphism and Urinary 8-OHdG Levels With Lung Cancer Susceptibility: A Hospital-Based Case-Control Study in Turkey

High incidence and poor prognosis of lung cancer make it a major health problem worldwide. Although smoking is a major cause of lung cancer, only some smokers develop lung cancer, which suggests that there is a genetic predisposition in some individuals. 8-OHG is an important oxidative base lesion and may elevate due to cancer and smoking. It is repaired by 8-hydroxyguanine DNA glycosylase 1 (OGG1), which has several polymorphisms. Although the Ser326Cys polymorphism is consistently associated with a range of cancers, findings about this polymorphism and lung cancer risk are contradictory. To date, no study has examined this association in the Turkish population. We conducted a case-control study to investigate the association between OGG1 Ser326Cys polymorphism and the risk of lung cancer using PCR-RFLP. We also evaluated gene-smoking interaction and excretion of urinary 8-OHdG. Our results suggest that the OGG1 Ser326Cys polymorphism is not a genetic risk factor for lung cancer, and that the heterozygous genotype is associated with a significantly reduced risk for lung cancer. The levels of 8-OHdG did not correlate with the polymorphism and smoking. Larger association studies are needed to validate our findings, and mechanistic studies are needed to elucidate the underlying molecular mechanisms of this association.