Impact of Mycotoxin Metabolites Deepoxy-Deoxynivalenol and Beta-Zearalenol on Bovine Preimplantation Embryo Development in the Presence of Acetonitrile.

The quality of animal feed is increasingly affected by weather conditions, high humidity, and damage to grains, which have led to various mycotoxin-producing moulds. The aim of this study was to determine the effects of the combination of deepoxy-deoxynivalenol and beta-zearalenol on the development of preimplantation bovine embryos, the extent to which the presence of both mycotoxin metabolites affects the development of in vitro cultured bovine embryos, or whether the effect of both toxins enhances embryotoxicity. Ovaries were transported from the abattoir to the laboratory and, after maturation and fertilisation, zygotes were placed in an embryo culture medium (IVC) with different mycotoxin metabolite concentrations diluted in acetonitrile. It was found that the blastocyst rate of cleaved embryos was affected by 1 µL acetonitrile in 400 µL medium (0.25%) compared to the group without acetonitrile. For this reason, it was decided to use acetonitrile as a control group, and the desired mycotoxin metabolite concentrations were diluted in the lowest possible amount of acetonitrile (0.5 µL) that could be accurately added to the study groups. There was no statistical difference when the higher mycotoxin metabolite concentrations were added.

Motor imagery helps updating internal models during microgravity exposure.

Skilled movements result from a mixture of feedforward and feedback mechanisms conceptualized by internal models. These mechanisms subserve both motor execution and motor imagery. Current research suggests that imagery allows updating feedforward mechanisms, leading to better performance in familiar contexts. Does this still hold in radically new contexts? Here, we test this ability by asking participants to imagine swinging arm movements around shoulder in normal gravity condition and in microgravity in which studies showed that movements slow down. We timed several cycles of actual and imagined arm pendular movements in three groups of subjects during parabolic flight campaign. The first, control, group remained on the ground. The second group was exposed to microgravity but did not imagine movements inflight. The third group was exposed to microgravity and imagined movements inflight. All groups performed and imagined the movements before and after the flight. We predicted that a mere exposure to microgravity would induce changes in imagined movement duration. We found this held true for the group who imagined the movements, suggesting an update of internal representations of gravity. However, we did not find a similar effect in the group exposed to microgravity despite the fact that the participants lived the same gravitational variations as the first group. Overall, these results suggest that motor imagery contributes to update internal representations of the considered movement in unfamiliar environments, while a mere exposure proved to be insufficient.NEW & NOTEWORTHY Gravity strongly affects the way movements are performed. How internal models process this information to adapt behavior to novel contexts is still unknown. The microgravity environment itself does not provide enough information to optimally adjust the period of natural arm swinging movements to microgravity. However, motor imagery of the task while immersed in microgravity was sufficient to update internal models. These results show that actually executing a task is not necessary to update graviception.

SPEXOR passive spinal exoskeleton decreases metabolic cost during symmetric repetitive lifting.

PURPOSE: Besides mechanical loading of the back, physiological strain is an important risk factor for low-back pain. Recently a passive exoskeleton (SPEXOR) has been developed to reduce loading on the low back. We aimed to assess the effect of this device on metabolic cost of repetitive lifting. To explain potential effects, we assessed kinematics, mechanical joint work, and back muscle activity. METHODS: We recruited ten male employees, working in the luggage handling department of an airline company and having ample experience with lifting tasks at work. Metabolic cost, kinematics, mechanical joint work and muscle activity were measured during a 5-min repetitive lifting task. Participants had to lift and lower a box of 10 kg from ankle height with and without the exoskeleton. RESULTS: Metabolic cost was significantly reduced by 18% when wearing the exoskeleton. Kinematics did not change significantly, while muscle activity decreased by up to 16%. The exoskeleton took over 18-25% of joint work at the hip and L5S1 joints. However, due to large variation in individual responses, we did not find a significant reduction of joint work around the individual joints. CONCLUSION: Wearing the SPEXOR exoskeleton decreased metabolic cost and might, therefore, reduce fatigue development and contribute to prevention of low-back pain during repetitive lifting tasks. Reduced metabolic cost can be explained by the exoskeleton substituting part of muscle work at the hip and L5S1 joints and consequently decreasing required back muscle activity.

Bite force in subjects with complete dentition.

Bite force is the condition, expression and measure of the masticatory function. The purpose of this study was to examine, by means of a newly constructed electronic gnathodynamometer, the values of maximal bite forces in subjects with complete dentition, the time in which they express 50% and 75% respectively of the total forces value, and the shape of the bite curve during testing. The obtained data was statistically analyzed with respect to gender and age. Analysis of the variance confirmed the finding that there was no statistically significant correlation between the values of forces and subjects' age, but there was a statistically significant difference between males and females in the values of the bite forces in the front segment, as well as between the values of the force on anterior and posterior teeth. The correlation between the time T1 posterior right and T1 posterior left, and between T1 and T2 for anterior teeth are statistically significant. Analysis of the bite curves suggests that males "bite" shorter than females with a sharper peak of the curve. Numerical values and bite curves should be a diagnostic factor in the further follow-up of subjects or in the choice of prosthodontic therapy.

Stability analysis of four-point walking.

The aim of the experiment reported here was to determine the static and dynamic stability of two-point stance phases when walking on hands and knees at different speeds. In addition, we defined the methods and predicted the consequences of including two-point stance phases into crutch assisted functional electrical stimulation (FES) walking. Crawling on hands and knees was performed at three speeds by five healthy male persons. With twelve joint-position markers placed on the subject, we determined two stability indices for every instant of gait. We analysed the peak values of these two indices during the two-point stance phases. The results indicate that we have to ensure the proper position of the centre of gravity to increase the speed of walking. To reach speeds, lower than 0.6 m/s, it is not necessary to include statically unstable phases. The shift of the centre of gravity towards and across the leading stability edge can result in getting into the dynamically unstable state. Considering the results we can effectively introduce two-point stance phases into crutch assisted FES walking and therefore increase the speed and energy effectiveness of walking

Quantitative thin-layer chromatographic identification of dental base alloys.

In the corrosively aggressive medium of the oral cavity, the use of identical dental alloys requires identification of the existing metal construction. One of the methods allowing this identification is quantitative thin-layer chromatography with anodic sampling. Using a 4.5-V battery and suitable electrolytes, seven dental alloys for fixed and removable dentures based on cobalt were analysed. Chromatograms of alloy samples were developed with a mixture of acetone and 2 M HCl. Scanning of the thin-layer chromatographic spots produced chromatographic curves and the area under the curve was proportional to the content of cobalt in the alloy studied. Regression analysis showed a very high coefficient of correlation (r=0.999) between the area of the spot and the proportion of cobalt.

The simulation and calculation of the fatigue of the lower complete denture in function by means of the finite element analysis.

This paper presents a finite element analysis, by which the stress distribution during function of a lower jaw acrylic-resin complete denture can be shown. The geometry of a prosthesis has been approximated by measuring, its elementary dimensions, as well as the dimensions of the characteristic cross-sections, on an already completed denture. Based upon these dimensions a mesh, (a three-dimensional network diagram) of finite elements was made. The results obtained are presented both graphically and numerically. The equivalent fatigue stresses, according to von Mises' energetic theory of firmness, expressed in MPa (or in N/mm2), are also shown. The results obtained enable us to gain an insight into lower complete denture fatigue, and could also be used when optimizing the shape of a denture. Furthermore, they could indicate possible causes of the fatigue fractures of a denture, particularly in the area between the left and the right canines.

[Goals and scientific achievements of the Institute of Oncology]. / Stremljenja i strucno-naucna dostignuca Instituta za onkologiju.

The Institute of oncology represents an oncological center which renders the measures of prevention, early detection and diagnostic of tumours and multidisciplinary strategy for antitumour treatment, including rehabilitation of patients suffering from tumours. To fulfil the above mentioned aims the Institute is organized in ten completely operative units and several functional centres and committees. The paper presents only few aspects of diagnostic and treatment of tumour, and the implementation of the programmes and targets of individual organizational units within the Institute. This orientation is particularly actual now when epidemiological studies show an increase of disease and mortality incidence in the region of Vojvodina.

Protocol of the diagnostic, therapy and follow-up of differentiated thyroid cancer.

The Protocol of the multidisciplinary diagnostic treatment and follow-up of differentiated thyroid cancers, made in the Institute of Oncology in Sremska Kamenica, is described. It is in use in this institution from 1990. It is in concordance with general oncology principles and follows the guidelines of the International Union Against Cancer (UICC) concerning this problem.

[Perinatal care]. / Perinatalna zastita.

In the Republic of Croatia, the perinatal mortality, as an indicator of perinatal care, has decreased from 38.6% in 1950-54 to 10.9% in 1989 which means that today it is on the low mortality level like in the Middle- and West-European countries. The decline of perinatal mortality is especially evident after 1985. There are pronounced differences within the different regions of the Republic of Croatia, the lowest perinatal mortality is in the town of Zagreb and in the central Croatia, while the highest one in the region of Bjelovar, Slavonia and Dalmatia. Comparing the data from 29 maternity hospitals and taking into account a decrease in the number of hospitals with high perinatal mortality (48% in 1972 to zero in 1990) and an increase in the number of hospitals with low mortality (11 or 38% with mortality less than 10% in 1990), an increase of the delivery frequency completed by cesarean section was found: in 1990 there were 31% of the maternity hospitals with more than 10%, 45% with 6-10% and 24% with less than 6% of cesarean sections. Over recent years the maternity hospitals are better supplied with the necessary medical equipment: in 1990 97% of the hospitals were provided with cardiotocographs, 97% with ultrasound apparatuses and 90% with baby incubators. A sufficient number of specialists in gynecology and obstetrics is available, while there are lacking 21 specialists in pediatrics--neonatology, what is one third of the required number.(ABSTRACT TRUNCATED AT 250 WORDS)

[Influence of heat treatment on silver-palladium alloy microstructure]. / Utjecaj toplinske obrade na mikrostrukturne promjene srebro-paladijeve legure.

Cast dental alloys, even those made of precious metals, are not homogeneous. In order to ensure a high-quality cast, it was necessary to determine optimal casting temperature and additional heat treatment to allow for homogenization of the cast in the microarea of the dendritic structure to occur which, in turn, implies chemical inertia of the metal construction to the organic medium of the mouth. A number of melting, homogenizing and aging tests showed the optimal regimen for bringing an Ag-Pd alloy to the level of hardness of the tooth enamel (about 330 HV 0.1) to consist of a technological treatment involving the following procedures: casting at 1100--1150 degrees C, homogenization at 850 degrees C, quenching in water and 20-min precipitation at 350 degrees C.

Analysis of metal diffusion from crown to the human teeth.

Proton induced X-ray emission spectroscopy (PIXE) has been used to determine the intensity of metals from crowns in human teeth. In order to measure elements distribution across the tooth section, proton beam (3 MeV) has been collimeted to provide a spatial resolution of 300 microns. The samples were selected according to the time of insertion of crowns and the kind of alloys they were made of. The results show the intensities of gold, zinc and copper in abutment teeth. It was not found any intensity of paladium and amount of silver was not significant.

[The value of preoperative intracavitary radiation in uterine carcinoma]. / Vrednost preoperativnog intrakavitarnog zracenja kod karcinoma materice.

The analysis comprised 240 uterine carcinomas: 145 carcinomas of the cervix and 95 carcinomas of the corpus uteri. Preoperatively 100 patients--57 with the carcinoma of the cervix and 43 with the carcinoma of the uterine body--were radiated with Co60 intracavitary. In the first stage of the carcinoma of the cervix a five-year survival in primarily operated patients amounted to 74.30% and in the group of preoperatively intracavitary radiated patients to 83%. In patients with the stage I carcinoma of the corpus uteri a five-year survival proved to be 69.57% if primarily operated and 93.75% if preoperatively radiated. Local relapses were recorded in 33 patients surgically treated for carcinoma of the uterine cervix and in 9 patients surgically treated for the carcinoma of the uterine body. In both these localizations the relapses were more frequent in the group primarily operated patients: in patients with the primarily operated carcinoma of the cervix the relapses occurred in 20.69% and in preoperatively radiated patients in 3.4% of cases. The same observations were recorded in the carcinoma of the corpus uteri (11.51% : 6.97%). This means that the relapses were six times as frequent in patients with the primarily operated carcinoma of the uterine cervix and about 1.65 times as frequent in those with the primarily operated carcinoma of the corpus uteri as in intracavitary radiated patients.