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Abstract  

Instrumental neutron activation analysis (INAA) was applied to determine Ba, Br, Ca, Cl, Fe, K, Mg, Mn, Na, P, Sr and Zn in bovine and porcine rib bones. Precise results were obtained in analyses of freeze-dried cortical and trabecular bones separately, and also of whole bone ashes. Cortical tissues presented higher concentrations of Ba, Ca, Mg, Mn, Na, P, Sr and Zn than those obtained in trabecular ones. Comparisons were also made between the results obtained for bovine and porcine rib bones.

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Carotenoids are among the most widespread and important pigments in living organisms. They are found in common foods and vegetables. The characteristic pattern of alternating single and double bonds in the polyene backbone enables them to absorb excess energy from other molecules. The nature of the specific end groups on carotenoids may effect their polarity, thus solubility ranges from acetone to hexane. Because of this wide range of polarity, specific extraction and separation procedures are required. In these procedures use of planar chromatography in food analysis might seem a minor aspect of carotenoid analysis. This review describes available data on analysis of carotenoids by thin-layer chromatography (TLC). It has been found that petroleum ether, acetone, and hexane are the major mobile phases used for TLC. Thin-layer chromatography was found to have the potential to be the first choice for analysis of carotenoids in biological samples. The uses of other, orthogonal chromatographic methods, for example HPLC, spectroscopy (mass spectroscopy), scanning densitometry, and image analysis with TLC can enable precise analysis of carotenoids.

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Abstract  

Fatty acid are the major energy source for the myocardium, thus radiolabeled fatty have often employed as heart imaging agent to localize ischemia and as potential probes of myocardial metabolism. This paper presents the synthesis of phenyl-pentadecanoic acid (PPA) by alkylation reaction and Wollf-Kishner method. Finally, PPA was iodinated with thallium trifluoroacetate on localizing para-position of phenyl ring and radioiodine was exchanged. The overall chemical yield was 20%, labelling yield 95%, radiochemical purity 98%. Tissues distribution of mice shows that IPPA was very high activity in mice heart muscle. Autoradiogram of mouse section at 2 min is clear.

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Orvosi Hetilap
Authors: László Andrássy, Gyula Maros, István János Kovács, Ágnes Horváth, Katalin Gulyás, Éva Bertalan, Anikó Besnyi, Judit Füri, Tamás Fancsik, Zoltán Szekanecz, and Harjit Pal Bhattoa

A csontszövet és a geológiai képződmények szerkezeti felépítése közötti hasonlóság lehetővé teszi, hogy a csontszövet szervetlen részét matematikai modellekkel közelítsük. Az elemi összetétel ellenőrizhető a lézerindukált plazmaspektroszkópiai és induktív csatolású plazmaoptikai emissziós spektrometriás mérésekből meghatározott elemoxidkoncentráció-értékekkel. A számításokból és a laboratóriumi mérésekből egyértelműen következik, hogy a csontszövet tulajdonságait elsősorban a hidroxiapatit határozza meg. A szervetlen csontszerkezet igen jól tanulmányozható a lézerindukált plazmaspektroszkópiai technikával megbízhatóan mérhető kalcium-oxid-koncentrációértékek eloszlásainak segítségével. Jelen tanulmányban a szerzők hím szarvasmarha lábszárcsontjaiból készült vékonycsiszolatokon szelvény menti, lézerindukált plazmaspektroszkópiai mérésekből számított kalcium-oxid-koncentráció eloszlásai mutatják be. A kalcium-oxid-koncentrációértékek felületi eloszlásait, „gyakorisági eloszlási” görbék támasztják alá. A több csoportba sorolt kalcium-oxid-koncentrációértékek alapján a corticalis és trabecularis csontszerkezet élesen megkülönböztethető. A szerzők a csontokon elvégzett kvantitatív komputertomográfiái mérésekből számított attenuációs együttható (összsűrűség) és geológiában használt „ρ”-sűrűség között szignifikáns pozitív korrelációt találtak. Továbbá a kiszámított „ρ”-sűrűség és a meghatározott átlag-kalcium-oxid-koncentrációértékek inverz korrelációt mutattak. Orv. Hetil., 2014, 155(45), 1783–1793.

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Abstract  

Boron concentration of plasma, feces, urine and body tissues from sheep fed with borated water (100 mg B/l) and tap water were determined by neutron-induced prompt gamma-ray analysis to elucidate boron metabolism. The B level in plasma and urine increased rapidly and the B content of feces increased greatly. The B concentrations in body tissues (liver, kidney, spleen, thyroid and muscle) of B dosed sheep were ten times higher than those of tap water administered sheep.

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Abstract  

In vivo behavior of biomaterial is dependent on the site of implantation. Characterization by atomic element transfers versus the implantation duration is a quantitative approach to the phenomenon. Here, bioactive coral is implanted in ovine, porcine and rabbit thighbones and not in sheep jawbones as previously reported. Biopsies extracted between 1 and 24 weeks are analysed by fast neutron activation. Mineral composition of the coral is greatly modified: Ca, P, Mg and Sr concentrations become comparable to those of mature bone some months after the implantation. Results suggest a bioactive resorption followed by apatite formation.

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Abstract  

Instrumental neutron activation analysis (INAA) with gamma-ray spectrometry was applied to determine As, Ca, Cd, Cl, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Mo, Na, Sb, Se and Zn in the Brazilian agroindustrial by-products. These materials are widely used in ruminant feeding. The results obtained were compared with requirement and maximum tolerable concentrations. The general conclusions from the data obtained were: (1) many by-products presented concentrations of some essential elements lower than the requirement concentrations, while in some concentrations of Cr, Fe, Mg and Se exceeded by a little the maximum tolerable concentrations, (2) the elements As, Cd, Hg and Sb, generally considered toxic, showed concentrations lower than maximum tolerable values.

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Abstract  

Bioassay and dosometry models are needed to estimate intakes of radionuclides, and to calculate radiation doses to target tissues following such in takes. Because of the diversity of exposure materials, individual biological variabilities, and the general lack of adequate bioassay information and knowledge of the metabolism of radionuclides, current models are based mostly on empiricism. This paper describes biokinetic/dosimetry models for U, Am, and Cm. They are based on experimental data developed from studies in dogs that inhaled one of the above radionuclides in specific chemical forms and specific particle sizes. The models, which are based on similar biological principles, and, therefore, have similar structure, are applied to the very sparse human bioassay data available from cases of exposure to either U, Am, or Cm. The results thus far indicate that the lung retention for the different actinides are well described by the models, that urinary bioassay data can be described within limited time periods, and that the fecal excretion rate is not adequately described. Improvements in modeling are predicted on increased publication of human bioassay data, and better cooperative interaction between model developers and health protection professionals responsible for industrial bioassay programs.

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Pain relief using drugs with high efficacy provides significant improvement in the patients’ lives. Drugs like lamotrigine (LTG) and gabapentin (GBP) have the ability to overcome the symptoms of neuropathic pain. Aim: The present study offers a comparative analysis of LTG and GBP efficacy in a rat model of nociceptive pain after single administration. Method: Sixty-three Wistar-Bratislava rats randomized into 7 groups were included: a control group treated with saline solution and 6 groups treated with different doses of LTG and GBP. Nociceptive responses to thermal and mechanical stimulations were evaluated before and after drug administration, at different time intervals, using paw pressure and hot plate tests. The obtained data were statistically analyzed, with significance at p value < 0.05. Results: LTG 100 mg/kg and 50 mg/kg presented a significant analgesic effect in both mechanical and thermal tests, 1 and 2 hours after administration. GBP 100 mg/kg increased latency time in hot plate test. The effect of both anticonvulsant drugs occurred rapidly after administration, but had a short duration. Conclusions: LTG and GBP had an analgesic effect in a single dose administration. The effect of LTG was more evident since it was observed in both tests. Their effect was dose dependent.

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Abstract  

Linezolid is the first of new class of antibiotics, the oxazolidinones, and exhibits activity against many gram-positive organisms, including vancomycin-resistant Enterococcus faecium, methicillin-resistant Staphylococcus aureus, and penicillin-resistant Streptococcus pneumoniae. Aim of the study: Linezolid was to label with I-131 and potential of the radiolabeled antibiotic was to investigate in inflamed rats with Saureus (S. aureus) and sterile inflamed rats with turpentine oil. Linezolid was labeled with I-131 by iodogen method. Biodistribution of [131I]linezolid was carried out in bacterial inflamed and sterile inflamed rats. Radiolabeling yield of [131I]linezolid was determined as 85 ± 1% at pH 2. After injecting of [131I]linezolid into bacterial inflamed and sterile inflamed rats, radiolabeled linezolid was rapidly removed from the circulation via the kidneys. Binding of [131I]linezolid to bacterial inflamed muscle (T/NT = 77.48 at 30 min) was five times higher than binding to sterile inflamed muscle (T/NT = 14.87 at 30 min) of rats. [131I]linezolid showed good localization in bacterial inflamed tissue. It was demonstrated that [131I]linezolid can be used to detect S. aureus inflammation in rats.

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