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Authors have long been guided by the following premise in their research, educational, professional and publishing activities. Components of the Integrated Transport Infrastructure (ITI) of Slovakia, including roads, should be designed, built, managed, maintained, recycled (decomposed) at a reasonable price, in reasonable quality, respecting the relevant requirements of users, residents and sustainable development throughout life cycle. Elements of ITI Slovakia, as important landscape ecological elements, should be designed with respect to aesthetic principles considering the cultural and natural wealth of Slovakia. Slovak technical universities have recently been criticized for teaching 50-years-old curriculum. The authors dare to disagree with the statement and, due to their scientific profile, pre-sent their partial outputs of a holistic approach to the sustainability of transport structures with a priority focus on pavement. In the intentions of the above mentioned, it could perhaps be partly convergently concluded that they learn new things in the field of transport construction, but under the old names.

Asphalt pavement is among the most widespread road surfaces. For their design, assessment, and service life, it is necessary to evaluate the deformation characteristics of asphalt mixtures, which include the complex modulus of rigidity. Two-point (2PB-TR) and four-point (4PB-PR) flexural tests are used to determine these. The scientific paper focuses on the evaluation of the complex modulus as a function of varying temperature and frequency. The results of the study indicated that both methods provide significant information on the behaviour of asphalt mixtures under different loading conditions. Four-point bending may be more sensitive to changes in deformation properties than two-point bending. This finding is of fundamental importance when analysing the influence of different factors on the mechanical properties of asphalt mixtures. Measurements were performed at temperatures of 0°C, 10°C and 20°C and frequencies of 1 Hz, 5 Hz, 10 Hz, 15 Hz and 20 Hz. Validation of the different measurement methods was carried out on the comparison asphalt mix AC 11 O PMB 45/80-75.

The quality of a road is affected by its correct design, the appropriate use of materials, the effects of the climate, and the technological discipline. The deformation properties and fatigue of asphalt layers are important for the design and assessment of semi-rigid and flexible pavements. The assessment of deformation properties is performed by means of a dynamic impact test and the fatigue life of a particular asphalt mixture. An evaluation of the fatigue life is based on decreases in resistance or increases in deformations in different binders and mixtures. The test methods for the design and control of pavement construction materials determine the basic conditions valid for flexible matter. The Two-Point Bending Test was used for determining the deformation characteristics and the fatigue of asphalt mixtures at the Department of Construction Management in Zilina.

The deformational properties of asphalt mixtures measured by dynamic methods and fatigue allow a design the road to suit the expected traffic load. Quality of mixtures is also expressed by the resistance to permanent deformation. Complex modulus of stiffness and fatigue can reliably characterize the proposed mixture of asphalt pavement. The complex modulus (E*) measurement of asphalt mixtures are carried out in laboratory of Department of Construction Management at University of Žilina by two-point bending test method on trapezoid-shaped samples. Today, the fatigue is verified on trapezoid-shaped samples and is assessed by proportional strain at 1 million cycles (ε6). The test equipment and software is used to evaluate fatigue and deformation characteristics.

A Tunnel Traffic & Operation Simulator is a device of the Centre of Transport Research at the University of Žilina. The Simulator allows managing technological equipment of virtual two-tube highway tunnel, which is interconnected with simulation of vehicle traffic in tunnel. Changes of the traffic-operation states and other equipment are reflecting at the simulated traffic, as well as simulations of various emergency events in traffic initiate changes in tunnel detecting and measuring devices. It is thus possible to simulate emergency states, which can be affected by various faults of technology as well as by climatic conditions. The solutions can be found in irreplaceable experiences of Slovak road tunnel operators, changes of trafficoperation states, visualizations of operator technological display screens, technological devices labelling in order to increase operational safety of road tunnels.

Cultural monuments are one of the strongest stakeholders at the regional level of tourism in the Czech Republic. There is a huge potential for cooperation between destination management and cultural monuments at the regional level. However, these possibilities are not fully established yet. The article is based on the survey conducted among managers of cultural monuments in the selected region of the Czech Republic to demonstrate the importance of cooperation between these two subjects. On the basis of the survey and analysis of the possibilities of cooperation between tourism industry and cultural monuments at the regional level, the new ways of cooperation are recommended.

Ventilation system of road tunnel is one of the most important parts of the tunnel safety equipment, especially in view of the emergency event in the tunnel with fire. Last year we presented the testing and the first in situ measurements of our project entitled “Models of formation and spread of fire to increase safety of road tunnels”. With regard to our project schedule we performed also the second in situ experiment. Other part of this paper deals with computer simulations of fires of a selected Slovak road tunnel.

Road emergency events are very dangerous, especially if they happen in tunnels. If such an event occurs with the presence of fire, self-evacuation is the most important. From experience from catastrophic events in Alpine tunnels, people can only have a few minutes to rescue. It was also reason that a lot of changes in technology and safety tunnel equipment have been legislatively adopted. Then if we want to help rescue people, we need experienced tunnel operators, who know the principles of tunnel ventilation control with fire and smoke. This paper is about simulation of emergency events in virtual tunnel of Tunnel Traffic & Operation Simulator (Simulator) and about simulations of smoke stratification on the basis of Computer Fluid Dynamics (CFD) models.

Within the project entitled “Models of formation and spread of fire to increase safety of road tunnels”, it was necessary to devise a method how to record airflow velocity during the fire in situ tests in road tunnels. Project is in first year of its solution so one testing measurement was performed to check the functionality of anemometers selected for this project and the first in situ measurement was also performed just a few days ago.

Tunnels, constructions used to shorten transport routes and to improve road safety, are specific engineering structures where the safe operation is very important. Tunnel Traffic & Operation Simulator (Simulator) was created as a solution of research task focused on increasing safety in road tunnels within the framework of the project “Centre of Transport Research (CVD)” funded by European Regional Development Fund (ERDF). The Simulator is located on Faculty of Civil Engineering of the University of Žilina (Slovakia) and is adapted to control the tunnel in two operator’s mode which are functionally convertible. They can during the operation of the simulator control the tunnel's technology and operation in normal conditions and in exceptional situations. Thanks to this, they could work under the pressure with non-performance threat to the tunnel technology and safety of their users. The coordinator checks and assesses the correctness of their conduct.

Background: The histopathological structure of malignant tumours involves two essential compartments - the tumour parenchyma with the actual transformed cells, and the supportive tumour stroma. The latter consists of specialized mesenchymal cells, such as fibroblasts, macrophages, lymphocytes and vascular cells, as well as of their secreted products, including components of the extracellular matrix, matrix modifying enzymes and numerous regulatory growth factors and cytokines. In consequence, the tumour stroma has the ability to influence virtually all aspects of tumour development and progression, including therapeutic response.Aim: In this article we review the current knowledge of tumor stroma interactions in urothelial carcinoma and present various experimental systems that are currently in use to unravel the biological basis of these heterotypic cell interactions.Results: For urothelial carcinoma, an extensive tumour stroma is quite typical and markers of activated fibroblasts correlate significantly with clinical parameters of advanced disease. Another clinically important variable is provided by the stromal expression of syndecan-1.Conclusion: Integration of markers of activated stroma into clinical risk evaluation could aid to better stratification of urothelial bladder carcinoma patients. Elucidation of biological mechanisms underlying tumour-stroma interactions could provide new therapeutical targets. [ABSTRACT FROM AUTHOR]

We used an integrative approach combining cranio-dental characters, mitochondrial and nuclear data and acoustic data to show the presence in the genus Miniopterus of a cryptic species from the Maghreb region. This species was previously recognised as Miniopterus schreibersii (Kuhl, 1817). Miniopterus maghrebensis sp. nov. can be differentiated from M. schreibersii sensu stricto on the basis of cranial characters and from mitochondrial DNA and microsatellite evidence. Although slight external morphological and acoustic differences were noted between the two species, these criteria alone did not allow reliable species identification from live animals. Based on the specimens identified morphologically and/or genetically, the distribution range of M. maghrebensis sp. nov. extends from northern Morocco to south of the High Atlas Mountains and northern Tunisia. The new cryptic species is found in sympatry with M. schreibersii s.str. near coastal regions of North Africa.

Background: Fatty acid-induced apoptosis and ER stress of pancreatic β-cells contribute to the development of type 2 diabetes, however, the molecular mechanisms involved are unclear., Aims: In this study we have tested the role of caspase-2 and suggested ER stress mediator JNK in saturated fatty acid-induced apoptosis of the human pancreatic β-cells NES2Y., Results: We found that stearic acid at apoptosis-inducing concentration activated ER stress signaling pathways, i.e. IRE1α, PERK and ATF6 pathways, in NES2Y cells. During stearic acid-induced apoptosis, JNK inhibition did not decrease the rate of apoptosis nor the activation of caspase-8, -9, -7 and -2 and PARP cleavage. In addition, inhibition of JNK activity did not affect CHOP expression although it did decrease the induction of BiP expression after stearic acid treatment. Caspase-2 silencing had no effect on PARP as well as caspase-8, -9 and -7 cleavage and the induction of CHOP expression, however, it also decreased the induction of BiP expression. Surprisingly, caspase-2 silencing was accompanied by increased phosphorylation of c-Jun., Conclusions: We have demonstrated that caspase-2 as well as JNK are not key players in apoptosis induction by saturated fatty acids in human pancreatic β-cells NES2Y. However, they appear to be involved in the modulation of saturated fatty acid-induced ER stress signaling, probably by a mechanism independent of c-Jun phosphorylation., (Copyright © 2013 S. Karger AG, Basel.)

The direct fusion methods for repair of spondylolytic defects of the lumbar spine have recently been replaced by transpedicular screw fixation of the affected segment, in combination with PLIF, TLIF or ALIF procedures. However, in clearly indicated cases, such as a younger patient with no intervertebral disc degeneration and only minimal or no displacement of the vertebra, the direct repair techniques have a great advantage over transpedicular fixation because they preserve segmental motion The paper reports on a patient with spondylolysis at L3 who underwent surgery combining the Tokuhashi and Matsuzaki and the Gillet and Petit techniques, which involved a system of transpedicular screws, rods and sublaminar hooks supplemented with a cross-connector to support the base of the spinous process. After surgery, the patient reported pain relief and return to normal activities and CT examination showed bony union of both spondylolytic defects.

PURPOSE OF THE STUDY To evaluate retrospectively a group of patients with hyperextension injury to the cervical spine who were treated at the Department of Spinal Surgery of the University Hospital in Motol, Prague, between 2003 and 2006. MATERIAL The group comprised 22 patients, 17 men (77 %) and five women (23 %) in the age range of 35 to 81 years, with an average of 59.5 years. All patients had, in association with the injury, neurological deficit of varying degree. METHODS All patients underwent X-ray and magnetic resonance imaging examination and received methylprednisolone according to the National Acute Spinal Cord Injury Study (NASCIS) 2 trial. Eleven patients had urgent surgery within 24 hours of injury; eight patients were operated on within an interval of 3 days to 2 months because of the seriousness of their state and multiple morbidity; and three patients were treated conservatively. Neurological deficit in terms of upper- and lower-limb mobility was evaluated by the American Spinal Injury Association (ASIA) motor score. The values obtained for the urgently operated patients and for those operated on after a time interval were compared by Wilcoxons two-sample test. The other aspects evaluated included trauma aetiology, level of spinal cord injury, manner of treatment, and intra-operative and post-operative complications. RESULTS The most frequent cause of injury was a low-height fall (13 patients; 59 %); car accidents ranked second (9 patients; 41 %). In five patients (22.7 %) ebriety was found. Eighteen patients had no skeletal injury (81.8 %). Four patients (18.2 %). Four patients (18.2 %) suffered fractures of articular or spinous processes, but the anterior column skeleton was intact in all. The segment most frequently affected by myopathy was C3-C4, then C4-C5 and C5-C6. Decompression was carried out to the extent of myopathy; and in the adjacent segments only if significant stenosis was present. In both subgroups of surgically treated patients (urgent and delayed management), comparisons of the ASIA scores at the time of injury and at one-year follow-up showed no significat improvement in post-operative mobility, as evaluated by Wilcoxons two-sample test at a level of significance a = 5 %. No intra-operative or post-operative complications, except for early death, were recorded. In all patients the wound healed by first intention and no loosening of instrumentation was foud on follow-ups at the out-patient departments. DISCUSSION Although the greatest narrowing of the spinal canal due to spondylosis occurs at the C5-C6 segment, the C4-C5 segment sustained most injuries. Although some relevant papers report no significant difference in improved neurological deficit between patients treated surgically and those undergoing conservative therapy, we prefer surgical management, in most of the cases from the anterior approach, which allows us to remove dorsal osteophytes and perform careful decompression to prevent damage to nerve structures and to preserve those which are still intact. There was no significant difference in the outcome between urgent and delayed trauma management, which is unusual amongst other injuries associated with neurological lesions and this indicates that the timing of surgery must be strictly individual and should be carried out at a time when operative benefit outweighs operative burden. The surgical treatment used should, in the first place, lead to early recuperation and rehabilitation. CONCLUSIONS Hyperextension injuries of the cervical spine are usually associated with serious neurological deficit. A correct algorithm of examination will result in good treatment outcomes. However, these injuries require a therapy that is long-lasting and difficult, with a need for cooperation of anaesthesiologists, spinal surgeons, physical therapists and, last but not least, psychologists. Key words: cervical spine, hyperextension injury, spondylosis, myelopathy.

Group A streptococcal strains were isolated from the throats of 46 children suffering from scarlet fever. For detection of erythrogenic toxins (ETs), the culture supernatants were concentrated 100 times by ethanol precipitation and solubilisation in acetate buffer. ELISA was used to identify ETA and double immunodiffusion to identify ETB and ETC. The presence of the ETA gene was detected by a specific DNA probe. ETA (alone or in combination with ETB and/or ETC) was found in 51.9% of the strains, ETB (alone or in combination with ETA and/or ETC) in 76.9% and ETC (in combination with ETA and ETB) in 28.9%. Only 5.8% of strains did not produce any detectable ET. In SDS-PAGE, supernatants of ETB-producing strains showed a pronounced band in either the region of the proteinase zymogen or the active proteinase. There was no correlation between the type of erythrogenic toxin and the serological M or T type of the producing strain. The mitogenic potency of culture supernatants did not differ significantly irrespective of the toxin type(s) present. Culture supernatants of strains without a detectable amount of the known ETs were highly mitogenic, indicating the production of other streptococcal mitogens. A correlation with clinical symptoms was determined with regard to exanthema and fever. Strains producing two or three toxins caused a more intense exanthema. Patient temperature was higher (greater than or equal to 38 degrees C) when the infecting strain produced ETB. The toxin-producing patterns of the strains of this study were compared with those isolated during the last epidemic outbreak of scarlet fever in East Germany.

During a two-week expedition, the prevalence of rheumatic heart disease (RHD) and the prevalence of group A streptococcal infections was investigated in a group of Yakut families of about 600 persons. In the 478 examined persons no clear-cut RHD was identified, but possible participation of rheumatic etiology in heart changes was not excluded in one adult. Group A streptococci were grown from pharyngeal swabs from 13.3% of the 202 persons examined, in the absence of any overt streptococcal disease in the settlement at the time of screening. Streptococci of at least six M-types were present among the population. Titres of antistreptolysin 0 greater than or equal to 250 u. and of antideoxyribonuclease-B greater than or equal to 1200 u. were found in 21% and 18%, respectively, of the 205 examined individuals. The bacteriological and serological data combined suggested a rather high streptococcal transmission rate in the settlement in the recent past, the pattern of which was reminiscent of the pattern of streptococcus spread in heavily interconnected population groups of the moderate climate. Possible reasons for the absence of definite RHD are discussed.

Highly selected group A streptococci, 108 strains isolated from different groups of individuals, were tested for binding of aggregated human IgG which had been pre-incubated in fresh human serum. All strains displayed resistance to phagocytosis typical of M-producing strains. Among 73 strains isolated from sporadic cases of acute glomerulo-nephritis (AGN), 34 (47 per cent) bound the aggregates. All of 26 type 12 group A streptococci but none of 15 type 49 strains proved positive in the test system. Furthermore, one type 1 and one type 18 strain were positive. All 9 type 49 strains isolated in a minor epidemic of AGN proved negative. Twenty-six strains of type 12 group A streptococci were isolated during three different prospective studies in which no cases of AGN had occurred; all these strains bound aggregates in the presence of fresh serum. Thus, it was found that the capacity to bind aggregates in the presence of fresh serum was strongly associated with--though not limited to--group A streptococci carrying the type 12 antigen. However, this characteristic is not common to all nephritogenic strains, since all type 49 group A streptococci were negative in the test system.

A controlled trial was undertaken to test I.R.S. 19 (a commercial intranasal spray) versus placebo in the prevention of acute respiratory diseases (ARD) in 825 maternity-school children in three cities; another control group of 327 children received neither I.R.S. 19 nor placebo. The spraying was done twice a day for a total of 20 spraying days in each child; sprayings were interrupted on weekends and during absence, the mean spraying period being 34 calendar days. During the 6-month study (1 November to 30 April) the children were monitored for ARD morbidity causing absence from school. A total of 1,585 such ARD cases occurred; their etiology was not investigated. The indices evaluated were: total duration of ARD-associated absence, ARD incidence, and mean duration of one illness. With the administration schedule used, I.R.S. 19 did not, in an overall evaluation, surpass placebo in any of these indices in either normal children or a subgroup of children with presumed enhanced ARD susceptibility.

Rabbit type-specific opsonic antibodies to type 1 and type 12 streptococci were isolated by affinity chromatography on immobilized phage-enzyme extract. They were tested by precipitation in gel, bactericidal test and radioimmunoassay. Only type-specific activities were demonstrated. These activities were distributed homogeneously according to avidity. No suggestion of opsonizing and precipitating activities being separable from each other was found. These highly purified rabbit antibodies were marked by radioiodination and used to titrate human anti-M antibodies by competition. These marked antibodies were also used for the study of type-specific antigenic determinants on streptococcal antigens.

In a prospective study (1961-1972) the incidence of rheumatic fever (RF), development of rheumatic heart disease (RHD) and penicillin prophylaxis efficacy were investigated in 300 000 children and 70 000 adults. Only patients whose index attack met the modified Jones' criteria were included; all were enrolled in a prophylaxis programme (i. m. benzathine-penicillin). The RF incidence decreased from an initial 61.2 attacks per 100 000 in children and 42.9 in adults to below 10 by 1969 and remained low thereafter. In total, 541 children (209 with carditis) and 176 adults (108 with carditis) were followed up for 5.5 years (average) after an index attack. At final examination, no valvular involvement was detected where previous attacks had been without clinical carditis. Patients studied from time of the primary attack with carditis (211) had a very favorable prognosis: only up to 3.5% had developed a moderate to severe heart lesion by the end of the study. However, of 68 adult patients followed up only from the time of recurrence with carditis and often having had a prolonged rheumatic history: 23.5% had a moderate to severe heart lesion and a further 20.6% had died of RHD by the end of the study. Prophylaxis efficacy calculated as a cumulative attack-recurrence rate per 100 patients and over a 5-year interval was 2.72 in protected as against 64.75 in unprotected children (mostly failing to comply with prophylaxis); in adults, the respective values were 1.3 and 24.92. The prevalence of serious residual RHD may be expected to decrease substantially in the future, starting with the younger age groups.