The quality assessment of the University hospital bone bank in Central Serbia: the second audit after fourteen years.

We analyzed the prevalence and predisposing factors for the overall rejection rate after retrieval of 267 fresh femoral head allografts over the past 7 years. The present study aimed to assess the quality system of institutional bone banking that can provide high-standard allografts with a low infection rate. Retrospective analysis of bone banking from June 2013 to December 2019 was conducted on 267 donors and 153 recipients. Of the 267 donated femoral heads, 74 were rejected, giving an overall rejection rate of 27.71%. The leading cause of allograft rejection was the inability to perform serology tests due to donor death; the absence of serological tests itself, and the donor refusal to perform the serology 6-month retest in 42 donors (15.72%). At retrieval, 12 allografts were positive, giving an overall contamination rate of 4.49%. Seven (2.62%) of the 267 allografts failed the blood screening tests. Thirteen allografts (4.86%) were discarded because of suspected damage to the packaging or disuse during surgery. An infection rate of 1.30% was found following transplantation. Over the past 7 years of bone banking, our results show that the overall rejection rate and the allograft-related infection rate correlate with international standards. The leading cause of allograft rejection was the inability to perform serology tests due to donor death and their refusal to perform the serology retests. Besides stringent aseptic allograft handling, donor motivation to participate in bone banking is extremely important for its efficient functioning.

Soil and Sand Contamination with Canine Intestinal Parasite Eggs as a Risk Factor for Human Health in Public Parks in Nis (Serbia).

Regarding geographical distribution and clinical relevance, the most common canine geohelminths are Toxocara canis, ancylostomatids, and Trichuris vulpis. Canine intestinal parasites from the soil and sand present an important potential serious human health hazard, especially for the children preschool and school - age. This paper aimed to establish the degree of contamination of soil and sand with zoonotic parasites from the canine feces and the degree of risk they could pose for human health in public places and playgrounds in the city of Nis. Our parasitological study involved 200 soil samples and 50 sand samples from the public parks in the city of Nis in southeastern Serbia (43°19'15″N, 21°53'45″ E). From several locations, about 100 g of soil and sand was collected based on the bioclimatic indices. Parasitological diagnosis was performed using conventional qualitative and quantitative coprological methods, abiding by the recommendations about the diagnosis of parasitic diseases. In 38 - 46 % of soil samples and 40 % of sand samples seven species of endoparasites were diagnosed. In the samples of soil, a medium and high degree of contamination with the ascarid T. canis (14 - 22 %) was detected, as well as a low and medium degree of contamination with ancylostomatids (4 - 12 %), and in the samples of sand, a variable degree of contamination with the helminths T. canis (26 %) and A. alata (16 %) was found. A statistically significant difference was found in the contamination with A. alata eggs between the samples of sand and samples of soil. The studied public surfaces represent the reservoir of zoonotic parasites, which is a public health problem requiring a synergistic action of several factors to be successfully resolved, i.e. the implementation of prevention, surveillance, and control measures.

Libyan Thymus capitatus essential oil: antioxidant, antimicrobial, cytotoxic and colon pathogen adhesion-inhibition properties.

AIMS: In the present work, the Libyan wild-growing Thymus capitatus essential oil (EO) was evaluated for its biological properties. METHODS AND RESULTS: Carvacrol (68.19%) and thymol (12.29%) were found to be the main compounds of the oil. Antioxidant properties, determined by 2,2-diphenylpicrylhydrazyl (DPPH) assay, revealed that IC50 values were 119, 403 and 105 µg ml(-1) for oil, thymol and carvacrol respectively. Microdilution method showed strong antibacterial and especially antifungal potential. Tetrazolium (MTT) colorimetric assay indicated moderate cytotoxicity towards human cell lines MRC-5, HCT 116 and HT-29 (IC50 = 30-150 µg ml(-1)). In adhesion-inhibition assay oil and main compounds reduced adhesion of Escherichia coli and Listeria monocytogenes on colon cells HT-29 (51 and 39% of inhibition against L. monocytogenes and E. coli respectively). CONCLUSIONS: Essential oil of Th. capitatus showed moderate cytotoxic activity, together with excellent antimicrobial effect, in particular against fungi, and significant potential to reduce pathogen colonization in colon. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report that EO of Th. capitatus could protect against colonization of pathogens to colon epithelium. Thymus capitatus from Libya should be recognized as possible new source of natural antioxidants, antimicrobials as well as possible source of new chemotherapeutics.

Influence of irradiation time on subsurface degree of conversion and microhardness of high-viscosity bulk-fill resin composites.

OBJECTIVES: To evaluate the influence of irradiation time on degree of conversion (DC) and microhardness of high-viscosity bulk-fill resin composites in depths up to 6 mm. MATERIALS AND METHODS: Four bulk-fill materials (Tetric EvoCeram Bulk Fill--TECBF; x-tra fil--XF; QuixFil--QF; SonicFill-SF) and one conventional nano-hybrid resin composite (Tetric EvoCeram--TEC) were irradiated for 10, 20, or 30 s at 1,170 mW/cm(2). DC and Knoop microhardness (KHN) were recorded after 24-h dark storage at five depths: 0.1, 2, 4, 5, and 6 mm. Data were statistically analyzed using ANOVA and Bonferroni's post-hoc test (α = 0.05). RESULTS: With increasing bulk thickness, DC and KHN significantly decreased for TEC. TECBF and SF showed a significant decrease in DC and KHN at 4-mm depth after 10-s irradiation, but no decrease in DC after 30-s irradiation (p > 0.05). XF and QF demonstrated no significant DC decrease at depths up to 6 mm after irradiation of at least 20 s. At 4-mm depth, all materials tested achieved at least 80 % of their maximum DC value, irrespective of irradiation time. However, at the same depth (4 mm), only XF and QF irradiated for 30 s achieved at least 80 % of their maximum KHN value. CONCLUSIONS: Regarding DC, the tested bulk-fill resin composites can be safely used up to at least 4-mm incremental thickness. However, with respect to hardness, only XF and QF achieved acceptable results at 4-mm depth with 30 s of irradiation. CLINICAL RELEVANCE: Minimum irradiation times stated by the manufacturers cannot be recommended for placement of high-viscosity bulk-fill materials in 4-mm increments.

Ongoing mumps outbreak in Novi Sad, the autonomous province of Vojvodina, Serbia, January to April 2012.

From 16 January to 30 April 2012, a total of 119 cases of mumps were notified in Novi Sad, Serbia. Of these cases, 89 (75%), were among students. The average age of cases was 22 years-old (range 3-37). The outbreak is still ongoing in Novi Sad and is spreading to other parts of the Vojvodina province. As of 30 April, 209 cases have been notified in the province among those 119 from Novi Sad.

Electron energy transfer rate coefficients of carbon dioxide.

An extensive set of integral cross sections (ICSs) for electron impact vibrational excitation of the CO(2) molecule has been used to calculate electron energy transfer rate coefficients. The ICSs for electron impact symmetric stretch vibrational excitation are measured by using a high resolution double trochoidal electron spectrometer, while ICSs for the bending and asymmetric vibrations have been adopted from previous publications. Calculations of the energy transfer rate coefficients are performed for the equilibrium conditions in the mean electron energy range from 0 to 11 eV. By use of extended Monte Carlo simulations, electron energy distribution functions (EEDFs) and electron energy transfer rate coefficients are determined in the nonequilibrium conditions, for low and moderate values of the electric field over gas number density ratios, E/N, up to 150 Td. Contributions of higher vibrational levels are emphasized. The results are compared with the data available in the literature.

A biofilm exists on healthy mucosa of the paranasal sinuses: a prospectively performed, blinded, scanning electron microscope study.

OBJECTIVES: Based on our hypothesis that biofilm is nothing else but normal, otherwise abundantly colonised mucosal mucous blanket, the aim of this study was to check out whether bacterial biofilm exists exclusively at the diseased mucosal surfaces or at healthy mucosa of paranasal sinuses as well. DESIGN: Prospective and blinded. SETTING: Tertiary academic hospital. PARTICIPANTS: The patients suffering from the diseases not related to the chronic inflammation of the paranasal sinuses. Mucosal tissue samples from healthy sphenoid sinuses were taken from 48 patients who underwent pituitary gland surgery and from ethmoidal sinuses mucosa of the 17 patients who underwent endonasal endoscopic orbital decompression because of Graves' disease. MAIN OUTCOME MEASURES: The samples were submitted blindly along with similar samples from patients with chronic rhinosinusitis to two scanning electron microscope experts. In all samples the looked for the main signs of biofilm presence of: the 'towers', rod-shaped bacteria and water channels. RESULTS: Signs of biofilm presence were found in 45 out of 48 pituitary gland surgery patients (94%) and in all of 17 EEOD patients (100%). CONCLUSIONS: Our study showed the presence of the biofilm at the surface of the healthy mucosa of the paranasal sinuses. This suggests that perhaps so called bacterial biofilm is nothing else but regular respiratory mucosal blanket, a part of the mucociliary system itself, containing a great number of bacteria.

Babesia bovis: continuous cultivation in a microaerophilous stationary phase culture.

The protozoan parasite Babesia bovis, a causative agent of bovine babesiosis, has been continuously cultivated in a settled layer of bovine erythrocytes. Lowered oxygen tension within the layer of host erythrocytes results in a darkening of infected cultures and provides a rapid means of evaluating parasite growth. Deprivation of carbon dioxide causes the merozoites to accumulate in the medium rather than involving new erythrocytes. When separated from the culture, these extraerythrocytic parasites retain their infectivity. Parasites produced in vitro are morphologically identical to parasites from the blood of infected cattle and are susceptible to antibabesial drugs.

Isolation, experimental transmission, and characterization of causative agent of Potomac horse fever.

Potomac horse fever, a disease characterized by fever, anorexia, leukopenia, and occasional diarrhea, is fatal in approximately 30 percent of affected animals. The seasonal occurrence of the disease (June to October) and evidence of antibodies to the rickettsia Ehrlichia sennetsu in the serum of convalescing horses suggested that a related rickettsia might be the causative agent. Such an agent was isolated in cultured blood monocytes from an experimentally infected pony. This intracytoplasmic organism was adapted to growth in primary cultures of canine blood monocytes. A healthy pony inoculated with these infected monocytes also developed the disease. The organism was reisolated from this animal which, at autopsy, had pathological manifestations typical of Potomac horse fever. Cross serologic reactions between the newly isolated agent and antisera to 15 rickettsiae revealed that it is related to certain members of the genus Ehrlichia, particularly to Ehrlichia sennetsu. Since the disease occurs in other parts of the United States as well as in the vicinity of the Potomac River, and since it has also been reported in Europe, the name equine monocytic ehrlichiosis is proposed as being more descriptive.

Bovine babesiosis: protection of cattle with culture-derived soluble Babesia bovis antigen.

Adult Hereford (Bos taurus) cattle were protected from severe reactions and death caused by the tick-borne protozoan hemoparasite Babesia bovis, 3 months after vaccination with a cell culture--derived immunogen. The immunogen consisted of filtered, freeze-dried supernatant fluid collected from long-term cultures of Babesia bovis in vitro. It was reconstituted with saponin adjuvant and injected twice subcutaneously at 2-week intervals. Serum collected from vaccinated cattle caused thickening of the merozoite surface coat, aggregation, and lysis of merozoites in vitro. This reaction was identical to that caused by serum from immune carrier cattle suggesting that the protective antigen present in culture fluids is merozoite surface coat antigen. No mortality occurred among vaccinated cattle, whereas mortality among unvaccinated cattle and Babesia bigemina--immune cattle was 62.5 percent indicating that immunity to bovine babesiosis is species-specific.

Magnetic resonance elastography hardware design: a survey.

Magnetic resonance elastography (MRE) is an emerging technique capable of measuring the shear modulus of tissue. A suspected tumour can be identified by comparing its properties with those of tissues surrounding it; this can be achieved even in deep-lying areas as long as mechanical excitation is possible. This would allow non-invasive methods for cancer-related diagnosis in areas not accessible with conventional palpation. An actuating mechanism is required to generate the necessary tissue displacements directly on the patient in the scanner and three different approaches, in terms of actuator action and position, exist to derive stiffness measurements. However, the magnetic resonance (MR) environment places considerable constraints on the design of such devices, such as the possibility of mutual interference between electrical components, the scanner field, and radio frequency pulses, and the physical space restrictions of the scanner bore. This paper presents a review of the current solutions that have been developed for MRE devices giving particular consideration to the design criteria including the required vibration frequency and amplitude in different applications, the issue of MR compatibility, actuation principles, design complexity, and scanner synchronization issues. The future challenges in this field are also described.

Combined FTIR and SEM-EDS study of Bi2O3 doped ZnO-SnO2 ceramics.

The effects of Bi(2)O(3) addition on the phase composition, microstructure and optical properties of ZnO-SnO(2) ceramics were investigated. Starting powders of ZnO and SnO(2) were mixed in the molar ratio 2:1. After adding Bi(2)O(3) (1.0 mol.%) this mixture was mechanically activated for 10 min in a planetary ball mill, uniaxially pressed and sintered at 1300 degrees C for 2 h. Far-infrared reflection spectra were measured (100-1000 cm(-1)). To investigate the occurred differences in FTIR spectra, the Bi(2)O(3)-doped sample was examined more carefully with a Perkin-Elmer FTIR spectrometer (Perkin Elmer, Waltham, MA, USA) connected with a Perkin-Elmer FTIR microscope and itemized points of interest were also studied with SEM-EDS.

Resonant vibrational excitation and de-excitation of N2(v) by low-energy electrons.

We have calculated cross sections and rate coefficients for low-energy electron impact excitation of the nitrogen molecule from vibrationally excited levels N2(v) 1-8. Calculations are performed in the 2Pig shape resonance energy region, from 0 to 5 eV. The cross sections are determined by using our recent integral cross section measurements of the ground level vibrational excitation and the most recent cross sections for elastic electron scattering, applying the principle of detailed balance. The rate coefficient calculations are performed for the Maxwellian electron energy distribution. By using extended Monte Carlo simulations, the electron energy distribution functions (EEDF) and the rate coefficients are also determined for the nonequilibrium conditions, in the presence of the homogeneous external electric field for the typical, moderate values of the electric field over gas number density ratios, E/N.

Resonant vibrational excitation and de-excitation of CO(v) by low energy electrons.

Integral cross sections and rate coefficients for vibrational excitation of the excited carbon-monoxide molecule, via the (2)Pi shape resonance in the energy region from 0 to 5 eV have been calculated. Cross sections are calculated by using our recently measured cross sections for the ground level CO excitation and the most recent cross sections for elastic electron scattering, applying the principle of detailed balance. Rate coefficients are calculated for Maxwellian electron energy distribution, with mean electron energies below 5 eV. By using extended Monte Carlo simulations, electron energy distribution functions (EEDF) and rate coefficients are determined in nonequilibrium conditions, in the presence of homogeneous external electric field. Nonequilibrium rates are calculated for typical, moderate values of the electric field over gas number density ratios, E/N, from 1 to 220 Td. Maxwellian and nonequilibrium rate coefficients are compared and the difference is attributed to a specific shape of the electron energy distribution functions under considered conditions.

Effects of fixed orthodontic appliances on subgingival microflora.

OBJECTIVES: Fixed orthodontic appliances cause plaque accumulation around bands and brackets. Since the microbiological composition of dental plaque is closely connected to periodontal tissue health, the aim of this study was to determine the effects of fixed orthodontic appliances on subgingival microflora and periodontal status. METHODS: This prospective study was carried out on 32 adolescents scheduled for fixed orthodontic treatment. Subgingival dental plaque samples and periodontal records (pocket probing depth and clinical attachment level) were obtained in four recording times: before bonding of fixed appliances (T0), 1 (T1), 3 (T2) and 6 (T3) months after the beginning of orthodontic therapy, in order to detect the changes in periodontopathic anaerobe microbial flora and its effects on periodontal status. RESULTS: The values of pocket probing depth, total number of microorganisms and number of patients with positive findings of Prevotella intermedia and other periodontopathic anaerobes increased from T0 to the maximum obtained in T2 recording time. Both clinical and microbiological values decreased 6 months after the beginning of orthodontic therapy. CONCLUSIONS: The therapy with fixed appliances may transitionally increase the growth of periodontopathogenic bacteria and consequently result in gingival inflammatory response but without destructive effect on deep periodontal tissues.

Kinetics of ultrasonic extraction of extractive substances from garden (Salvia officinalis L.) and glutinous (Salvia glutinosa L.) sage.

The kinetics of ultrasonic extraction of extractive substances (ES) from dry herbs of garden (Salvia officinalis L.) and glutinous (Salvia glutinosa L.) sage using petroleum ether, 70% ethanol or water at 40 degrees C, as well as the composition of dry extracts, were studied. The mechanism of ultrasonic extraction is confirmed to occur in two steps: first, dissolution of the ES near the particle surface (washing) and, second, diffusion from the solid particles to the bulk of the liquid extract (slow extraction). The process is described mathematically using three concepts of the unsteady diffusion through plant material, the film theory and the empirical equation of Ponomaryov. The yield of ES increases with increasing solvent polarity, and nearly the maximum concentration of ES in liquid extracts is achieved for about 20 min. The composition of extracts depends on both the extraction conditions applied and the plant material.

Purification and characterization of culture-derived exoantigens of Plasmodium falciparum.

An 83 kDa glycoprotein and a 100 kDa glycoprotein have been purified from the supernatant fluid of in vitro cultures of Plasmodium falciparum by conventional cation-exchange liquid chromatography, size exclusion high performance liquid chromatography, and anion-exchange high performance liquid chromatography. Both proteins exist as dimers in the native state and have been identified as parasite antigens by Western immunoblotting and by their specific reactivity in the indirect enzyme-linked immunosorbent assay. The N-terminal amino acid sequence of these two proteins has been determined and they are at least 90% homologous. The use of monospecific rabbit antisera raised against the individual pure proteins confirm their cross-reactivity. We postulate that the 83 kDa protein is a specific processing product of the larger 100 kDa protein. The presence of these proteins in the culture supernatant suggests they could both be derived from the merozoite surface coat and are potential protective antigens.

Pulsed blue laser curing of hybrid composite resins.

Clinical performance of light-curing composite restorations is greatly influenced by the quality of the curing-light. Currently used photopolymerization units have some important drawbacks, such as decreasing light output with time and distance, which results in a relatively low degree of conversion and shallow depth of cure, particularly of darker shades. Experiments with continuous argon laser polymerization showed overheating of the composite sample, as well as increased shrinkage of the material. In this study a pulsed laser, set at 468 nm (the maximum of the camphorquinone absorption coefficient), with 20-ns pulse duration, repetition rate of 10 Hz and energy of 10 mJ per pulse, was used as a light source. The aim of the study was to evaluate the effect of polymerization of light and dark shades of three different hybrid composites cured by pulsed laser at the surface and at 3.0 mm depth. The degree of conversion was measured by Fourier transform infrared spectroscopy (FTIR). Applying pulsed blue laser, significantly better results were obtained for both shades compared to standard polymerization values. Very weak dependence of the degree of conversion, between the surface measurements and those at 3.0 mm, were observed in the case of pulsed laser polymerization due to the piercing nanopulses and the monochromatic light at 468 nm.

Brain lipids in rat after chronic diazepam treatment.

Male Wistar rats with an initial weight of 170g were maintained on a nutritionally adequate diet, and diazepam was administered at a dose of 10 mg/kg/d. Control animals were pair-fed an adequate diet. The feeding was continued for 180 d, and the effects on brain lipid contents were studied. It was found that the contents of the phospholipids, phosphatidylethanolamine and phosphatidylserine, the monogalactosyl glycolipids, hydroxy and nonhydroxy fatty acyl galactocerebroside, sulfoglycolipids, and the gangliosides, GM1, GD1a, GD1b, and GT1b, were significantly reduced in the brain of diazepam-treated rats. There was a significantly increased content of phosphatidylinositol after 180 d of diazepam treatment. The results suggest that changes in brain lipid content may mediate the adaptive changes that occur upon prolonged exposure to diazepam.

Glomerulopathy in squirrel monkeys with acute Plasmodium falciparum infection.

The renal pathology of 9 squirrel monkeys (Saimiri sciureus) with acute Plasmodium falciparum infection was studied by light and electron microscopy. Endocapillary proliferative glomerulonephritis was the major pathological change observed. The peroxidase anti-peroxidase method demonstrated the presence of IgG, IgM, and P. falciparum antigens in the mesangium and basement membrane. These findings were consistent with those seen in humans with acute P. falciparum infection and indicates that squirrel monkeys are likely to be a good model for the study of renal pathology in malaria research.